Powered by Deep Web Technologies
Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Hydraulic fracturing-1  

SciTech Connect (OSTI)

This book contains papers on hydraulic fracturing. Topics covered include: An overview of recent advances in hydraulic fracturing technology; Containment of massive hydraulic fracture; and Fracturing with a high-strength proppant.

Not Available

1990-01-01T23:59:59.000Z

2

Detecting Fractures Using Technology at High Temperatures and...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Fractures Using Technology at High Temperatures and Depths - Geothermal Ultrasonic Fracture Imager (GUFI); 2010 Geothermal Technology Program Peer Review Report Detecting...

3

Detecting Fractures Using Technology at High Temperatures and...  

Broader source: Energy.gov (indexed) [DOE]

Fractures Using Technology at High Temperatures and Depths - Geothermal Ultrasonic Fracture Imager (GUFI) Presentation Number: 015 Investigator: Patterson, Doug (Baker Hughes...

4

The Fracture Toughness of Medium Density Fiberboard (MDF) Including the Effects of Fiber Bridging and Crack-Plane Interference  

E-Print Network [OSTI]

1 The Fracture Toughness of Medium Density Fiberboard (MDF) Including the Effects of Fiber Bridging University, Corvallis, OR, USA Abstract The fracture toughness of medium density fiberboard (MDF) as a function of crack length (R curve) was measured. Fracture toughness was determined from force

Nairn, John A.

5

NUMERICAL MODELING OF DEFORMATION AND FRACTURE OF WOOD INCLUDING HETEROGENEITY AND ANISOTROPY  

E-Print Network [OSTI]

NUMERICAL MODELING OF DEFORMATION AND FRACTURE OF WOOD INCLUDING HETEROGENEITY AND ANISOTROPY John A. Nairn Wood Science & Engineering, Oregon State University, USA Abstract The challenge in numerical modeling of wood is to have the model closely match the structure of a real specimen. The model

Nairn, John A.

6

Surfactant-enhanced spontaneous imbibition process in highly fractured carbonate reservoirs.  

E-Print Network [OSTI]

??Highly fractured carbonate reservoirs are a class of reservoirs characterized by high conductivity fractures surrounding low permeability matrix blocks. In these reservoirs, wettability alteration is… (more)

Chen, Peila

2011-01-01T23:59:59.000Z

7

Mobility control of chemical EOR fluids using foam in highly fractured reservoirs.  

E-Print Network [OSTI]

??Highly fractured and vuggy oil reservoirs represent a challenge for enhanced oil recovery (EOR) methods. The fractured networks provide flow paths several orders of magnitude… (more)

Gonzale?z Llama, Oscar

2011-01-01T23:59:59.000Z

8

Fracture Modeling of Crack Propagation in Wood and Wood Composites Including Crack Tip Processes and Fiber Bridging Mechanics  

E-Print Network [OSTI]

1 Fracture Modeling of Crack Propagation in Wood and Wood Composites Including Crack Tip Processes and Fiber Bridging Mechanics J. A. Nairn, N. Matsumoto Wood Science & Engineering, Oregon State University wood and wood composites develop process zones often consisting of fibers bridging the crack surfaces

Nairn, John A.

9

High-resolution fracture aperture mapping using optical profilometry Pasha Ameli,1  

E-Print Network [OSTI]

High-resolution fracture aperture mapping using optical profilometry Pasha Ameli,1 Jean E. Elkhoury] Fractures play an important role in the Earth's crust, often controlling both mechanical and transport of fracture surfaces and the contacts and void spaces between fracture surfaces at high spatial resolution (10

Elkhoury, Jean

10

Structural parameters The analytical model proposed here can explain high fracture  

E-Print Network [OSTI]

Structural parameters · The analytical model proposed here can explain high fracture toughness, P.J., et al., Engineering Fracture Mechanics, 2007. 74: p. 19281941. 4. Ritchie, R.O., et al Tensile strength Fracture toughness Composite properties E max S )~( ~ aJ III. Fracture toughness

Barthelat, Francois

11

Fracture Animation Based on High-Dimensional Voronoi Diagrams Sara C. Schvartzman  

E-Print Network [OSTI]

Fracture Animation Based on High-Dimensional Voronoi Diagrams Sara C. Schvartzman Stanford University Miguel A. Otaduy URJC Madrid Figure 1: Horses fractured by metal balls. These fractures emphasize be curved, and fracture patterns adapt to the impact and object properties. Abstract We propose a novel

Otaduy, Miguel A.

12

Proppant Fracture Conductivity with High Proppant Loading and High Closure Stress  

E-Print Network [OSTI]

PROPPANT FRACTURE CONDUCTIVITY WITH HIGH PROPPANT LOADING AND HIGH CLOSURE STRESS A Thesis by MATTHEW CHARLES RIVERS Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 2010 Major Subject: Petroleum Engineering PROPPANT FRACTURE CONDUCTIVITY WITH HIGH PROPPANT LOADING AND HIGH CLOSURE STRESS A Thesis by MATTHEW CHARLES RIVERS Submitted...

Rivers, Matthew Charles

2011-08-08T23:59:59.000Z

13

Fracture behavior of high-burnup spent-fuel cladding  

SciTech Connect (OSTI)

PCI-like, brittle-type failures, characterized by pseudocleavage-plus-fluting features in the fracture surface, branching cracks, and small diametral strain, were observed to occur at 292 to 325/sup 0/C in some batches of spent power-reactor fuel-cladding tubes under internal gas-pressurization and expanding-mandrel loading conditions in which the tests were not influenced by fission product simulants. Fractographic characteristics per se do not provide evidence for a PCI failure mechanism but should be deemed only as cooroborative in nature. Evaluation of TEM thin-foil specimens, obtained from regions adjacent to the brittle-type fracture sites, characteristically revealed extensive amounts of Zr/sub 3/O precipitates and a lack of slip dislocations. The precipitation of the Zr/sub 3/O phase appears to be enhanced by a high density of irradiation-induced defects. The brittle-type failure produced in the spent-fuel cladding tubes appears to be associated with segregation of oxygen to dislocation substructures and irradiation-induced defects, which leads to the formation of an ordered zirconium-oxygen phase of Zr/sub 3/O, an immobilization of dislocations, and minimal plastic deformation in the cladding material.

Chung, H.M.; Yaggee, F.L.; Kassner, T.F.

1983-10-01T23:59:59.000Z

14

Numerical modeling of time-lapse seismic data from fractured reservoirs including fluid flow and geochemical processes  

E-Print Network [OSTI]

Discrete Fracture Network (DFN) models. My seismic simulation study suggests that CO2 saturated reservoir shows approximately ten times more attenuation than brine saturated reservoir. Similarly, large P-wave velocity variation in CO2 saturated reservoir...

Shekhar, Ravi

2009-05-15T23:59:59.000Z

15

In-situ remediation of naturally occurring radioactive materials with high-permeability hydraulic fracturing  

E-Print Network [OSTI]

This thesis addresses the problem of removal of Naturally Occurring Radioactive Materials, NORM, and describes an effective alternative to the current treatment method for their removal. High-pen-meability fracturing, recently established...

Demarchos, Andronikos Stavros

2012-06-07T23:59:59.000Z

16

ECONOMIC RECOVERY OF OIL TRAPPED AT FAN MARGINS USING HIGH ANGLE WELLS AND MULTIPLE HYDRAULIC FRACTURES  

SciTech Connect (OSTI)

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a prograding turbidite complex through the use of hydraulically fractured horizontal or high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore. A high-angle well will be drilled in the fan-margin portion of a slope-basin clastic reservoir and will be completed with multiple hydraulic-fracture treatments. Geologic modeling, reservoir characterization, and fine-grid reservoir simulation will be used to select the well location and orientation. Design parameters for the hydraulic-fracture treatments will be determined, in part, by fracturing an existing test well. Fracture azimuth will be predicted by passive seismic monitoring of a fracture-stimulation treatment in the test well using logging tools in an offset well.

Mike L. Laue

1998-11-06T23:59:59.000Z

17

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures  

SciTech Connect (OSTI)

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a prograding turbidite complex through the use of hydraulically fractured horizontal or high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore.

Laue, M.L.

1999-11-01T23:59:59.000Z

18

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures  

SciTech Connect (OSTI)

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low energy deposits at the distal end of a protruding turbidite complex through use of hydraulically fractured horizontal of high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than conventional vertical wells while maintaining vertical communication between thin interbedded layers and the well bore.

Mike L. Laue

1998-05-29T23:59:59.000Z

19

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures  

SciTech Connect (OSTI)

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a propagating turbidite complex through the use of hydraulically-fractured horizontal or high-angle wells. The combination of a horizontal or high-angled well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thininterbedded layers and the well bore.

Mike L. Laue

1997-05-08T23:59:59.000Z

20

ECONOMIC RECOVERY OF OIL TRAPPED AT FAN MARGINS USING HIGH ANGLE WELLS AND MULTIPLE HYDRAULIC FRACTURES  

SciTech Connect (OSTI)

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a prograding turbidite complex through the use of hydraulically fractured horizontal or high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore. A high-angle well will be drilled in the fan-margin portion of a slope-basin clastic reservoir and will be completed with multiple hydraulic-fracture treatments. Geologic modeling, reservoir characterization, and fine-grid reservoir simulation will be used to select the well location and orientation. Design parameters for the hydraulic-fracture treatments will be determined, in part, by fracturing an existing test well. Fracture azimuth will be predicted by passive seismic monitoring of a fracture-stimulation treatment in the test well using logging tools in an offset well. The long radius, near horizontal well was drilled during the first quarter of 1996. Well conditions resulted in the 7 in. production liner sticking approximately 900 ft off bottom. Therefore, a 5 in. production liner was necessary to case this portion of the target formation. Swept-out sand intervals and a poor cement bond behind the 5 in. liner precluded two of the three originally planned hydraulic fracture treatments. As a result, all pay intervals behind the 5 in. liner were perforated and stimulated with a non-acid reactive fluid. Following a short production period, the remaining pay intervals in the well (behind the 7 in. liner) were perforated. The well was returned to production to observe production trends and pressure behavior and assess the need to stimulate the new perforations.

Mike L. Laue

2001-09-28T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Dynamic fluid loss in hydraulic fracturing under realistic shear conditions in high-permeability rocks  

SciTech Connect (OSTI)

A study of the dynamic fluid loss of hydraulic fracturing fluids under realistic shear conditions is presented. During a hydraulic fracturing treatment, a polymeric solution is pumped under pressure down the well to create and propagate a fracture. Part of the fluid leaks into the rock formation, leaving a skin layer of polymer or polymer filter cake, at the rock surface or in the pore space. This study focuses on the effects of shear rate and permeability on dynamic fluid-loss behavior of crosslinked and linear fracturing gels. Previous studies of dynamic fluid loss have mainly been with low-permeability cores and constant shear rates. Here, the effect of shear history and fluid-loss additive on the dynamic leakoff of high-permeability cores is examined.

Navarrete, R.C.; Cawiezel, K.E.; Constien, V.G. [Dowell Schlumberger, Tulsa, OK (United States)

1996-08-01T23:59:59.000Z

22

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures  

SciTech Connect (OSTI)

The distal fan margin in the northeast portion of the Yowlumne field contains significant reserves but is not economical to develop using vertical wells. Numerous interbedded shales and deteriorating rock properties limit producibility. In addition, extreme depths (13,000 ft) present a challenging environment for hydraulic fracturing and artificial lift. Lastly, a mature waterflood increases risk because of the uncertainty with size and location of flood fronts. This project attempts to demonstrate the effectiveness of exploiting the distal fan margin of this slope-basin clastic reservoir through the use of a high-angle well completed with multiple hydraulic-fracture treatments. The combination of a high-angle (or horizontal) well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore. The equivalent production rate and reserves of three vertical wells are anticipated at one-half to two-thirds the cost.

Mike L. Laue

1997-05-30T23:59:59.000Z

23

Parameter Estimates for High-Level Nuclear Transport in Fractured Porous Media  

E-Print Network [OSTI]

accurate description of the transport and dispersion of nuclear contam- ination through a granitic medium with a standard model for the transport and dispersion of a nuclear chain in an unfractured, singleParameter Estimates for High-Level Nuclear Transport in Fractured Porous Media Jim Douglas, Jr. #3

Douglas Jr., Jim

24

Control of cryogenic intergranular fracture in high-manganese austenitic steels  

SciTech Connect (OSTI)

The sources of cryogenic intergranular embrittlement in high-Mn austenitic steels and the conditions necessary for its control are examined. It is shown that the high-Mn alloys are inherently susceptible to intergranular embrittlement due to both their low grain boundary cohesion and heterogeneous deformation characteristics. Extrinsic sources of embrittlement which could account for the transition behavior are not observed. An Auger electron spectroscopy (AES) study shows no indication of impurity-segregation-induced embrittlement. No grain boundary precipitation is observed, and austenite stabilization does not ensure ductile fracture. The influence of chemistry modifications on the ductile-to-brittle transition behavior were also examined through additions of N, Cr, and C to binary Fe-31 Mn. Nitrogen additions increase the 77K yield strength at a rate of 2200 MPa per weight percent N, and increase the austenite stability, but also increase the susceptibility of ternary alloys to intergranular fracture. Quaternary Cr additions are effective in increasing the N solubility, and lower the transition temperature. Carbon additions result in complete suppression of intergranular fracture at 77K. Qualitatively significant changes in the deformation heterogeneity with chemistry modifications are not observed. The temper-toughening of Fe-Mn-Cr-N alloys is associated with the grain boundary segregation of boron and the redistribution of N. Both boron and carbon are expected to inhibit intergranular fracture through increases in grain boundary cohesion.

Strum, M.J.

1986-12-01T23:59:59.000Z

25

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures  

SciTech Connect (OSTI)

This project attempts to demonstrate the effectivensss of exploiting thin-layered, low energy deposits at the distal margin of a propagating turbinite complex through u se of hydraulically fractgured horizontal of high-angle wells. TGhe combinaton of a horizontal or high-angle weoo and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore.

Mike L. Laue

1998-02-05T23:59:59.000Z

26

Fracture of brittle multiphase materials by high energy water jets  

Science Journals Connector (OSTI)

High energy water jets are established in processing brittle, inhomogeneous materials like rocks and concrete. Despite their wide ... of application, the failure mechanisms of these materials, especially the infl...

A. Momber; R. Kovacevic

1996-02-15T23:59:59.000Z

27

FATIGUE AND FRACTURE BEHAVIOR OF HIGH TEMPERATURE MATERIALS  

E-Print Network [OSTI]

of damagetolerance in Ti3SiC,; (above the "ductile-brittle" transition temperature), where in fact, the plastic behavior in general is unusual for carbides and significant high-temperature deformation and damage are first is believed to be due to its layered structure and the metallic apparent. Of the two

Ritchie, Robert

28

Effects of alloying elements on microstructure, hardness, and fracture toughness of centrifugally cast high-speed steel rolls  

Science Journals Connector (OSTI)

A study was made of the effects of alloying elements on the microstructure, hardness, and fracture toughness of centrifugally cast high-speed steel (HSS) rolls. Particular emphasis was placed on the role of ha...

Chang Kyu Kim; Yong Chan Kim; Jong Il Park…

2005-01-01T23:59:59.000Z

29

Fracture Conductivity of the Eagle Ford Shale  

E-Print Network [OSTI]

conductivity is influenced by several variables including fracture surface roughness, fracture closure stress, proppant size, and proppant concentration. The proppant concentration within a fracture can significantly affect the magnitude of fracture...

Guzek, James J

2014-07-25T23:59:59.000Z

30

Fracture Behavior of a Laser Beam Welded High-strength Al-Zn Alloy  

Science Journals Connector (OSTI)

Abstract Laser beam welding of butt joints made of the newly developed high-strength Al-Zn alloy PA734 is conducted. A new approach of the Helmholtz-Zentrum Geesthacht is used to solve the problems of weldability and softening. The results of the fatigue, fatigue crack propagation and fracture toughness tests are discussed relating to the microstructural characteristics and the mechanical properties of the laser welded joints and compared to the base material. The obtained data can be used for the assessment of the damage tolerance behaviour of the laser welded integral aircraft structures made of Al-Zn alloys.

J. Enz; H. Iwan; S. Riekehr; V. Ventzke; N. Kashaev

2014-01-01T23:59:59.000Z

31

Fracture mechanics investigations on high-temperature gas-cooled reactor materials  

SciTech Connect (OSTI)

The prototype nuclear process heat plant and the high-temperature gas-cooled reactor need materials that can withstand temperatures up to 1223 K (950/sup 0/C). An elaboration of fracture mechanics concepts that holds for the complete temperature regime must consider all possible phenomena like creep damage and precipitation during exposure, etc. In tests on the Inconel-617, Hastelloy-X, and Nimonic-86 alloys with respect to fatigue crack growth, creep crack growth, and toughness (J integral R curves) up to 1273 K (1000/sup 0/C), the first creep crack growth results were obtained in helium to compare with the air results. It was shown that pure fatigue crack growth behavior can be described by linear elastic fracture mechanics up to 1273 K. An example of Hastelloy-X at 1223 K proves that evaluating fatigue crack growth according to the J intergral concept gives, within a small scatterband, the same results as by following the linear elastic concept. Hastelloy-X shows a decreasing fracture toughness with increasing temperatures. It is emphasized that the J integral concept holds only if creep deformation can be neglected. The experimental evidence at highest temperatures shows that the J integral R curve is not at all similar to that found at lower temperatures under ideal conditions. Creep crack growth for Nimonic-86 at 1073 less than or equal to T/K less than or equal to 1273 shows that crack growth at 1223 K in helium is found to be larger than in air. Problems arise when correlating the creep crack growth results. The application of the energy rate integral C* seems promising, but this has yet to be proven. A combination of long-term creep with fatigue crack growth is presently impossible.

Krompholz, K.; Bodmann, E.; Gnirss, G.K.; Huthmann, H.

1984-08-01T23:59:59.000Z

32

Investigation of temperature dependence of fracture toughness in high-dose HT9 steel using small-specimen reuse technique  

SciTech Connect (OSTI)

The temperature dependence of fracture toughness in HT9 steel irradiated to 3–145 dpa at 380–503 degrees*C was investigated using miniature three-point bend (TPB) fracture specimens. A miniature-specimen reuse technique has been established: the tested halves of subsize Charpy impact specimens with dimensions of 27 mm *3mm* 4 mm were reused for this fracture test campaign by cutting a notch with a diamond-saw in the middle of each half, and by fatigue-precracking to generate a sharp crack tip. It was confirmed that the fracture toughness of HT9 steel in the dose range depends more strongly on the irradiation temperature than the irradiation dose. At an irradiation temperature <430 *degreesC, the fracture toughness of irradiated HT9 increased with the test temperature, reached an upper shelf of 180—200 MPa*m^.5 at 350–450 degrees*C, and then decreased with the test temperature. At an irradiation temperature >430 degrees*C, the fracture toughness was nearly unchanged up to about 450 *degreesC and decreased slowly with test temperatures in a higher temperature range. Such a rather monotonic test temperature dependence after high-temperature irradiation is similar to that observed for an archive material generally showing a higher degree of toughness. A brittle fracture without stable crack growth occurred in only a few specimens with relatively lower irradiation and test temperatures. In this discussion, these TPB fracture toughness data are compared with previously published data from 12.7 mm diameter disc compact tension (DCT) specimens.

Baek, Jong-Hyuk; Byun, Thak Sang; Maloy, Stuart A.; Toloczko, Mychailo B.

2014-01-01T23:59:59.000Z

33

Advanced hydraulic fracturing methods to create in situ reactive barriers  

SciTech Connect (OSTI)

This article describes the use of hydraulic fracturing to increase permeability in geologic formations where in-situ remedial action of contaminant plumes will be performed. Several in-situ treatment strategies are discussed including the use of hydraulic fracturing to create in situ redox zones for treatment of organics and inorganics. Hydraulic fracturing methods offer a mechanism for the in-situ treatment of gently dipping layers of reactive compounds. Specialized methods using real-time monitoring and a high-energy jet during fracturing allow the form of the fracture to be influenced, such as creation of assymmetric fractures beneath potential sources (i.e. tanks, pits, buildings) that should not be penetrated by boring. Some examples of field applications of this technique such as creating fractures filled with zero-valent iron to reductively dechlorinate halogenated hydrocarbons, and the use of granular activated carbon to adsorb compounds are discussed.

Murdoch, L. [FRX Inc., Cincinnati, OH (United States)]|[Clemson Univ., SC (United States). Dept. of Geological Sciences; Siegrist, B.; Meiggs, T. [Oak Ridge National Lab., TN (United States)] [and others

1997-12-31T23:59:59.000Z

34

Poroelastic modeling of seismic boundary conditions across a fracture  

E-Print Network [OSTI]

on poroelasticity of fractures. Both authors would like toYork. Figure 3: For a high permeability fracture, the fluidpressure across the fracture is continuous, which can be

Schoenberg, M.A.; Nakagawa, S.

2006-01-01T23:59:59.000Z

35

MULTI-PHASE FRACTURE-MATRIX INTERACTIONS UNDER STRESS CHANGES  

SciTech Connect (OSTI)

The main objectives of this project are to quantify the changes in fracture porosity and multiphase transport properties as a function of confining stress. These changes will be integrated into conceptual and numerical models that will improve our ability to predict and optimize fluid transport in fractured system. This report details our progress on: (a) developing the direct experimental measurements of fracture aperture and topology and fluid occupancy using high-resolution x-ray micro-tomography, (b) quantifying the effect of confining stress on the distribution of fracture aperture, and (c) characterization of shear fractures and their impact on multi-phase flow. The three-dimensional surface that describes the large-scale structure of the fracture in the porous medium can be determined using x-ray micro-tomography with significant accuracy. Several fractures have been scanned and the fracture aperture maps have been extracted. The success of the mapping of fracture aperture was followed by measuring the occupancy of the fracture by two immiscible phases, water and decane, and water and kerosene. The distribution of fracture aperture depends on the effective confining stress on the nature of the rock and the type and distribution of the asperities that keep the fracture open. Fracture apertures at different confining stresses were obtained by micro-tomography covering a range of about two thousand psig. Initial analysis of the data shows a significant aperture closure with increase in effective confining stress. Visual descriptions of the process are shown in the report while detailed analysis of the behavior of the distribution of fracture aperture is in progress. Both extensional and shear fractures are being considered. The initial multi-phase flow tests were done in extensional fractures. Several rock samples with induced shear fracture are being studies, and some of the new results are presented in this report. These samples are being scanned in order to quantify the distribution of apertures and the nature of the asperities. Low resolution images of fluids in a sample with a shear fracture were performed and they provide the confidence that flow patterns and saturations could be determined in the future. A series of water imbibition tests were conducted in which water was injected into a fracture and its migration into the matrix was monitored with CT and DR x-ray techniques. The objective is to understand the impact of the fracture, its topology and occupancy on the nature of mass transfer between the matrix and the fracture. Counter-current imbibition next to the fracture was observed and quantified, including the influence of formation layering.

A.S. Grader; D. Elsworth; P.M. Halleck; F. Alvarado; A. Alajmi; Z. Karpyn; N. Mohammed; S. Al-Enezi

2005-06-15T23:59:59.000Z

36

Process for producing silicon nitride based articles of high fracture toughness and strength  

DOE Patents [OSTI]

A process for producing a silicon nitride-based article of improved fracture toughness and strength. The process involves densifying to at least 98% of theoretical density a mixture including (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 .mu.m and a surface area of about 8-12 m.sup.2 /g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 .mu.m and a surface area of about 2-4 m.sup.2 /g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. Optionally, the mixture may be blended with a binder and injection molded to form a green body, which then may be densified by, for example, hot isostatic pressing.

Huckabee, Marvin (Marlboro, MA); Buljan, Sergej-Tomislav (Acton, MA); Neil, Jeffrey T. (Acton, MA)

1991-01-01T23:59:59.000Z

37

Process for producing silicon nitride based articles of high fracture toughness and strength  

DOE Patents [OSTI]

A process for producing a silicon nitride-based article of improved fracture toughness and strength is disclosed. The process involves densifying to at least 98% of theoretical density a mixture including (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 [mu]m and a surface area of about 8-12 m[sup 2]/g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 [mu]m and a surface area of about 2-4 m[sup 2]/g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. Optionally, the mixture may be blended with a binder and injection molded to form a green body, which then may be densified by, for example, hot isostatic pressing.

Huckabee, M.; Buljan, S.T.; Neil, J.T.

1991-09-10T23:59:59.000Z

38

Damage & fracture of high-explosive mock subject to cyclic loading  

SciTech Connect (OSTI)

We use four-point bend specimen with a single shallow edge notch to study the fracture process in Mock 900-21, a PBX 9501 high explosive simulant mock. Subject to monotonic loading we determine quantitatively the threshold load for macroscopic crack initiation from the notch tip. The four-point bend specimen is then subject to cyclic loading in such a way that during the first cycle, the applied force approaches but does not exceed the threshold load determined from the monotonic loading test and in the subsequent cycles, the overall maximum deformation is maintained to be equal to that of the first cycle. It is expected and is also confirmed that no macroscopic damage and cracking occur during the first cycle. However, we observe that sizable macroscopic crack is generated and enlarged during the subsequent cycles, even though the applied force never exceeds the threshold load. Details of the process of damage fonnation, accumulation, and crack extension are presented and the mechanical mechanism responsible for such failure process is postulated and discussed.

Liu, Cheng [Los Alamos National Laboratory; Rae, Philip J [Los Alamos National Laboratory; Cady, Carl M [Los Alamos National Laboratory; Lovato, Manuel L [Los Alamos National Laboratory

2011-01-11T23:59:59.000Z

39

Fracture Blisters  

E-Print Network [OSTI]

21. McCann S, Gruen G. Fracture Blisters: A Review of thewith Lower Extremity Fracture: Results of a ProspectiveC, Koval K. Treatment of Fracture Blisters: A Prospective

Uebbing, Claire M; Walsh, Mark; Miller, Joseph B; Abraham, Mathew; Arnold, Clifford

2011-01-01T23:59:59.000Z

40

Investigation of Created Fracture Geometry through Hydraulic Fracture Treatment Analysis  

E-Print Network [OSTI]

Successful development of shale gas reservoirs is highly dependent on hydraulic fracture treatments. Many questions remain in regards to the geometry of the created fractures. Production data analysis from some shale gas wells quantifies a much...

Ahmed, Ibraheem 1987-

2012-11-30T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

A high liquid yield process for retorting various organic materials including oil shale  

DOE Patents [OSTI]

This invention is a continuous retorting process for various high molecular weight organic materials, including oil shale, that yields an enhanced output of liquid product. The organic material, mineral matter, and an acidic catalyst, that appreciably adsorbs alkenes on surface sites at prescribed temperatures, are mixed and introduced into a pyrolyzer. A circulating stream of olefin enriched pyrolysis gas is continuously swept through the organic material and catalyst, whereupon, as the result of pyrolysis, the enhanced liquid product output is provided. Mixed spent organic material, mineral matter, and cool catalyst are continuously withdrawn from the pyrolyzer. Combustion of the spent organic material and mineral matter serves to reheat the catalyst. Olefin depleted pyrolysis gas, from the pyrolyzer, is enriched in olefins and recycled into the pyrolyzer. The reheated acidic catalyst is separated from the mineral matter and again mixed with fresh organic material, to maintain the continuously cyclic process. 2 figs.

Coburn, T.T.

1988-07-26T23:59:59.000Z

42

High liquid yield process for retorting various organic materials including oil shale  

DOE Patents [OSTI]

This invention is a continuous retorting process for various high molecular weight organic materials, including oil shale, that yields an enhanced output of liquid product. The organic material, mineral matter, and an acidic catalyst, that appreciably adsorbs alkenes on surface sites at prescribed temperatures, are mixed and introduced into a pyrolyzer. A circulating stream of olefin enriched pyrolysis gas is continuously swept through the organic material and catalyst, whereupon, as the result of pyrolysis, the enhanced liquid product output is provided. Mixed spent organic material, mineral matter, and cool catalyst are continuously withdrawn from the pyrolyzer. Combustion of the spent organic material and mineral matter serves to reheat the catalyst. Olefin depleted pyrolysis gas, from the pyrolyzer, is enriched in olefins and recycled into the pyrolyzer. The reheated acidic catalyst is separated from the mineral matter and again mixed with fresh organic material, to maintain the continuously cyclic process.

Coburn, Thomas T. (Livermore, CA)

1990-01-01T23:59:59.000Z

43

Structural Reliability of Ceramics at High Temperature: Mechanisms of Fracture and Fatigue Crack Growth  

SciTech Connect (OSTI)

Final report of our DOE funded research program. Aim of the research program was to provide a fundamental basis from which the mechanical reliability of layered structures may be understood, and to provide guidelines for the development of technologically relevant layered material structures with optimum resistance to fracture and subcritical debonding. Progress in the program to achieve these goals is described.

Reinhold H. Dauskardt

2005-08-01T23:59:59.000Z

44

Fracture behavior of surface cracked wide plates of high strength steel containing overmatched repair welds  

SciTech Connect (OSTI)

This paper presents the experimental results of tests conducted using surface cracked wide plates containing overmatched repair weld joints. The deformation and fracture characteristics of the repair welded wideplates notched at the original weld deposit, repair weld and HAZ regions are discussed. The aim of this work was to investigate the effects of strength mis-match and notch position on the fracture performance of such complex weldments. Furthermore, the predictions of crack driving force using the Engineering Treatment Model for mis-matched welds (ETM-MM) procedure was compared with the results of the wide plates containing semielliptical surface cracks. For this study, 1/2K weld joints were prepared on 30 nm thick pipeline steel X65 plates by using a SAW process, resulting in 50% overmatching. Repair was performed at the cap side of the original joint up to half depth of plate thickness with a GMA welding process under hyperbaric conditions, leading to 41% yield strength overmatching. In order to assess the fracture behavior of these welds, surface cracked (semielliptic defects) wide plates containing original and repair welds were tested in tension at {minus}10 C. The surface cracked wide plate tests results have confirmed that overmatched repair weld metal can exert a significant effect on the deformation and fracture behavior of the wide plates. Wide plates containing root cracks clearly showed a shielding effect of the overmatched repair weld since it prevented development of through thickness ligament yielding.

Junghans, E.; Kocak, M.; Schwalbe, K.H. [GKSS Research Center, Geesthacht (Germany). Inst. of Materials Research

1996-12-01T23:59:59.000Z

45

Mapping brittle fracture zones in three dimensions: high resolution traveltime seismic tomography in a granitic pluton  

Science Journals Connector (OSTI)

......Company's Uranium mine restoration programme (ENRESA...studying the resolving power of a broad variety of...to study its resolving power we have performed several...Carmichael R.S. , 1982. Handbook of Physical Properties...prediction of the fracture system in the Albal granitic......

D. Martí; R. Carbonell; A. Tryggvason; J. Escuder; A. Pérez-Estaún

2002-04-01T23:59:59.000Z

46

Technical basis for flawed cylinder test specification to assure adequate fracture resistance of ISO high strength steel cylinder  

SciTech Connect (OSTI)

High pressure industrial gases (such as oxygen, nitrogen, argon, hydrogen, etc.) are stored and transported in portable cylinders. ISO TC58 SC3 has developed a draft specification 9809 for design and fabrication of high pressure cylinders with maximum tensile strength limitation of 1,100 N/mm{sup 2}. In order to extend the ISO 9809 rules for higher than 1,100 N/mm{sup 2} strength level cylinders, a working group WG14 was formed in 1989 to develop new rules to assure adequate fracture resistance. In 1994, WG14 recommended a simple, but unique flawed cylinder test method for design qualification of the cylinder and acceptance criteria to assure adequate fracture resistance. WG14 also recommended Charpy-V-Notch impact tests to control the required fracture resistance on production cylinders. This paper presents the technical basis that was employed in developing the flawed cylinder test method and acceptance criteria. The specification was developed for seamless steel cylinders having actual strength in the range of 1,100 to 1,400 N/mm{sup 2} and cylindrical section wall thickness in the range of 3mm to 10mm. Flawed cylinder tests were conducted on several hundred cylinders of varying sizes and strength levels. The specification requires to demonstrate LEAK-BEFORE-BREAK performance of the cylinder having flaw length equal to 1.6(O.D. {times} t{sub design}){sup 0.5} at failure pressure = (t{sub design}/t{sub actual}) {times} Design Pressure.

Rana, M.D. [Praxair, Inc., Tonawanda, NY (United States). Process and Systems R and D; Smith, J.H. [National Inst. of Standards and Technology, Gaithersburg, MD (United States). Metallurgy Div.; Tribolet, R.O.

1996-12-01T23:59:59.000Z

47

Technical basis for flawed cylinder test specification to assure adequate fracture resistance of ISO high-strength steel cylinder  

SciTech Connect (OSTI)

High-pressure industrial gases (such as oxygen, nitrogen, argon, hydrogen, etc.) are stored and transported in portable cylinders. ISO TC58 SC3 has developed a draft specification 9809 for design and fabrication of high-pressure cylinders with maximum tensile strength limitation of 1,100 N/mm{sup 2}. In order to extend the ISO 9809 rules for higher than 1,100 N/mm{sup 2} strength level cylinders, a working group WG14 was formed in 1989 to develop new rules to assure adequate fracture resistance. In 1994, WG14 recommended a simple, but unique flawed cylinder test method for design qualification of the cylinder and acceptance criteria to assure adequate fracture resistance. WG14 also recommended Charpy-V-notch impact tests to control the required fracture resistance on production cylinders. This paper presents the technical basis that was employed in developing the flawed cylinder test method and acceptance criteria. The specification was developed for seamless steel cylinders having actual strength in the range of 1,100 to 1,400 N/mm{sup 2} and cylindrical section wall thickness in the range of 3 to 10 mm. Flawed cylinder tests were conducted on several hundred cylinders of varying sizes and strength levels. The specification requires to demonstrate LEAK-BEFORE-BREAK performance of the cylinder having flaw length equal to 1.6 (o.d. {times} t{sub design}){sup 0.5} at failure pressure = (t{sub design}/t{sub actual}) x Design Pressure.

Rana, M.D. [Praxair, Inc., Tonawanda, NY (United States); Smith, J.H. [National Inst. of Standards and Technology, Gaithersburg, MD (United States). Metallurgy Div.; Tribolet, R.O. [Tribolet (R.O.), Van Wert, OH (United States)

1997-11-01T23:59:59.000Z

48

TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES IN THE  

Open Energy Info (EERE)

TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES IN THE TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES IN THE COSO GEOTHERMAL FIELD FROM ANALYSES OF SHEAR-WAVE SPLITTING Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES IN THE COSO GEOTHERMAL FIELD FROM ANALYSES OF SHEAR-WAVE SPLITTING Details Activities (1) Areas (1) Regions (0) Abstract: This project aims to improve understanding of the subsurface fracture system in the Coso geothermal field, located in the east central California. We applied shear-wave splitting technique on a set of high quality, locally recorded microearthquake (MEQ) data. Four major fracture directions have been identified from the seismograms recorded by the permanent sixteen-station down-hole array: N10- 20W, NS, N20E, and N40-45E,

49

MULTI-PHASE FRACTURE-MATRIX INTERACTIONS UNDER STRESS CHANGES  

SciTech Connect (OSTI)

The main objectives of this project are to quantify the changes in fracture porosity and multiphase transport properties as a function of confining stress. These changes will be integrated into conceptual and numerical models that will improve our ability to predict and optimize fluid transport in fractured system. This report details our progress on: (1) developing the direct experimental measurements of fracture aperture and topology using high-resolution x-ray microtomography, (2) modeling of fracture permeability in the presence of asperities and confining stress, and (3) simulation of two-phase fluid flow in a fracture and a layered matrix. The three-dimensional surface that describes the large-scale structure of the fracture in the porous medium can be determined using x-ray micro-tomography with significant accuracy. The distribution of fracture aperture is a difficult issue that we are studying and developing methods of quantification. The difficulties are both numerical and conceptual. Numerically, the three-dimensional data sets include millions, and sometimes, billions of points, and pose a computational challenge. The conceptual difficulties derive from the rough nature of the fracture surfaces, and the heterogeneous nature of the rock matrix. However, the high-resolution obtained by the imaging system provides us a much needed measuring environment on rock samples that are subjected to simultaneous fluid flow and confining stress. Pilot multi-phase experiments have been performed, proving the ability to detect two phases in certain large fractures. The absolute permeability of a fracture depends on the behavior of the asperities that keep it open. A model is being developed that predicts the permeability and average aperture of a fracture as a function of time under steady flow of water including the pressure solution at the asperity contact points. Several two-phase flow experiments in the presence of a fracture tip were performed in the past. At the present time, we are developing an inverse process using a simulation model to understand the fluid flow patterns in the presence of a fracture, and the interactions between fluid flow in the fracture and the adjacent matrix. Preliminary results demonstrate that the flow patterns are significantly impacted by the presence of the fracture. Bypassing is quantified and we expect to be able to extract from the modeling the distribution of properties in the fracture and the adjacent matrix.

A.S. Grader; D. Elsworth; P.M. Halleck; F. Alvarado; H. Yasuhara; A. Alajmi; Z. Karpyn

2002-10-28T23:59:59.000Z

50

FRACTURED PETROLEUM RESERVOIRS  

SciTech Connect (OSTI)

The four chapters that are described in this report cover a variety of subjects that not only give insight into the understanding of multiphase flow in fractured porous media, but they provide also major contribution towards the understanding of flow processes with in-situ phase formation. In the following, a summary of all the chapters will be provided. Chapter I addresses issues related to water injection in water-wet fractured porous media. There are two parts in this chapter. Part I covers extensive set of measurements for water injection in water-wet fractured porous media. Both single matrix block and multiple matrix blocks tests are covered. There are two major findings from these experiments: (1) co-current imbibition can be more efficient than counter-current imbibition due to lower residual oil saturation and higher oil mobility, and (2) tight fractured porous media can be more efficient than a permeable porous media when subjected to water injection. These findings are directly related to the type of tests one can perform in the laboratory and to decide on the fate of water injection in fractured reservoirs. Part II of Chapter I presents modeling of water injection in water-wet fractured media by modifying the Buckley-Leverett Theory. A major element of the new model is the multiplication of the transfer flux by the fractured saturation with a power of 1/2. This simple model can account for both co-current and counter-current imbibition and computationally it is very efficient. It can be orders of magnitude faster than a conventional dual-porosity model. Part II also presents the results of water injection tests in very tight rocks of some 0.01 md permeability. Oil recovery from water imbibition tests from such at tight rock can be as high as 25 percent. Chapter II discusses solution gas-drive for cold production from heavy-oil reservoirs. The impetus for this work is the study of new gas phase formation from in-situ process which can be significantly different from that of gas displacement processes. The work is of experimental nature and clarifies several misconceptions in the literature. Based on experimental results, it is established that the main reason for high efficiency of solution gas drive from heavy oil reservoirs is due to low gas mobility. Chapter III presents the concept of the alteration of porous media wettability from liquid-wetting to intermediate gas-wetting. The idea is novel and has not been introduced in the petroleum literature before. There are significant implications from such as proposal. The most direct application of intermediate gas wetting is wettability alteration around the wellbore. Such an alteration can significantly improve well deliverability in gas condensate reservoirs where gas well deliverability decreases below dewpoint pressure. Part I of Chapter III studies the effect of gravity, viscous forces, interfacial tension, and wettability on the critical condensate saturation and relative permeability of gas condensate systems. A simple phenomenological network model is used for this study, The theoretical results reveal that wettability significantly affects both the critical gas saturation and gas relative permeability. Gas relative permeability may increase ten times as contact angle is altered from 0{sup o} (strongly liquid wet) to 85{sup o} (intermediate gas-wetting). The results from the theoretical study motivated the experimental investigation described in Part II. In Part II we demonstrate that the wettability of porous media can be altered from liquid-wetting to gas-wetting. This part describes our attempt to find appropriate chemicals for wettability alteration of various substrates including rock matrix. Chapter IV provides a comprehensive treatment of molecular, pressure, and thermal diffusion and convection in porous media Basic theoretical analysis is presented using irreversible thermodynamics.

Abbas Firoozabadi

1999-06-11T23:59:59.000Z

51

Economic recovery of oil trapped at fan margins using high angle wells and multiple hydraulic fractures. Annual report, September 28, 1995--September 27, 1996  

SciTech Connect (OSTI)

The digital fan margin in the northeast portion of the Yowlumne field contains significant reserves but is not economic to develop using verticle wells. Numerous interbedded shales and deteriorating rock properties limit producibility. In addition, extreme depths (13,000 ft) present a challenging environment for hydraulic fracturing and artificial lift. Lastly, a mature waterflood increases risk because of the uncertainty with size and location of flood fronts. This project attempts to demonstrate the effectiveness of exploiting the distal fan margin of this slope-basin clastic reservoir through the use of a high-angle well completed with multiple hydraulic-fracture treatments. The combination of a high-angle (or horizontal) well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional verticle wells while maintaining verticle communication between thin interbedded layers and the wellbore. The equivalent production rate and reserves of three verticle wells are anticipated at one-half to two-thirds the cost.

Niemeyer, B.L.

1997-09-01T23:59:59.000Z

52

TRITIUM EFFECTS ON WELDMENT FRACTURE TOUGHNESS  

SciTech Connect (OSTI)

The effects of tritium on the fracture toughness properties of Type 304L stainless steel and its weldments were measured. Fracture toughness data are needed for assessing tritium reservoir structural integrity. This report provides data from J-Integral fracture toughness tests on unexposed and tritium-exposed weldments. The effect of tritium on weldment toughness has not been measured until now. The data include tests on tritium-exposed weldments after aging for up to three years to measure the effect of increasing decay helium concentration on toughness. The results indicate that Type 304L stainless steel weldments have high fracture toughness and are resistant to tritium aging effects on toughness. For unexposed alloys, weldment fracture toughness was higher than base metal toughness. Tritium-exposed-and-aged base metals and weldments had lower toughness values than unexposed ones but still retained good toughness properties. In both base metals and weldments there was an initial reduction in fracture toughness after tritium exposure but little change in fracture toughness values with increasing helium content in the range tested. Fracture modes occurred by the dimpled rupture process in unexposed and tritium-exposed steels and welds. This corroborates further the resistance of Type 304L steel to tritium embrittlement. This report fulfills the requirements for the FY06 Level 3 milestone, TSR15.3 ''Issue summary report for tritium reservoir material aging studies'' for the Enhanced Surveillance Campaign (ESC). The milestone was in support of ESC L2-1866 Milestone-''Complete an annual Enhanced Surveillance stockpile aging assessment report to support the annual assessment process''.

Morgan, M; Michael Tosten, M; Scott West, S

2006-07-17T23:59:59.000Z

53

Red Flag Warnings are in effect for much of Colorado today, including the area of the High Park Fire.  

E-Print Network [OSTI]

: This daily wildfire update is provided by the Colorado State Forest Service to keep you informed of current not cover all wildfires currently burning in Colorado, including smaller fires and those burning onlyPage 1 Red Flag Warnings are in effect for much of Colorado today, including the area of the High

Stephens, Graeme L.

54

Composting of soils/sediments and sludges containing toxic organics including high energy explosives. Final report  

SciTech Connect (OSTI)

Laboratory and pilot-scale experimentation were conducted to evaluate composting as an on-site treatment technology to remediate soils contaminated with hazardous waste at DOE`s PANTEX Plant. Suspected contaminated sites within the PANTEX Plant were sampled and analyzed for explosives, other organics, and inorganic wastes. Soils in drainage ditches and playas at PANTEX Plant were found to be contaminated with low levels of explosives (including RDX, HMX, PETN and TATB). Additional sites previously used for solvent disposal were heavily contaminated with solvents and transformation products of the solvent, as well as explosives and by-products of explosives. Laboratory studies were conducted using {sup 14}C-labeled explosives and {sup 14}C-labeled diacetone alcohol contaminated soil loaded into horse manure/hay composts at three rates: 20, 30, and 40%(W/W). The composts were incubated for six weeks at approximately 60{degree}C with continuous aeration. All explosives degraded rapidly and were reduced to below detection limits within 3 weeks in the laboratory studies. {sup 14}C-degradates from {sup 14}C-RDX, {sup 14}C-HMX and {sup 14}C-TATB were largely limited to {sup 14}CO{sub 2} and unextracted residue in the compost. Volatile and non-volatile {sup 14}C-degradates were found to result from {sup 14}C-PETN breakdown, but these compounds were not identified. {sup 14}C-diacetone alcohol concentrations were significantly reduced during composting. However, most of the radioactivity was volatilized from the compost as non-{sup 14}CO{sub 2} degradates or as {sup 14}C-diacetone alcohol. Pilot scale composts loaded with explosives contaminated soil at 30% (W/W) with intermittent aeration were monitored over six weeks. Data from the pilot-scale study generally was in agreement with the laboratory studies. However, the {sup 14}C-labeled TATB degraded much faster than the unlabeled TATB. Some formulations of TATB may be more resistant to composting activity than others.

Doyle, R.C.; Kitchens, J.F.

1993-07-01T23:59:59.000Z

55

Multi-Phase Fracture-Matrix Interactions Under Stress Changes  

SciTech Connect (OSTI)

The main objectives of this project are to quantify the changes in fracture porosity and multi-phase transport properties as a function of confining stress. These changes will be integrated into conceptual and numerical models that will improve our ability to predict and optimize fluid transport in fractured system. This report details our progress on: (a) developing the direct experimental measurements of fracture aperture and topology and fluid occupancy using high-resolution x-ray micro-tomography, (b) counter-current fluid transport between the matrix and the fracture, (c) studying the effect of confining stress on the distribution of fracture aperture and two-phase flow, and (d) characterization of shear fractures and their impact on multi-phase flow. The three-dimensional surface that describes the large-scale structure of the fracture in the porous medium can be determined using x-ray micro-tomography with significant accuracy. Several fractures have been scanned and the fracture aperture maps have been extracted. The success of the mapping of fracture aperture was followed by measuring the occupancy of the fracture by two immiscible phases, water and decane, and water and kerosene. The distribution of fracture aperture depends on the effective confining stress, on the nature of the rock, and the type and distribution of the asperities that keep the fracture open. Fracture apertures at different confining stresses were obtained by micro-tomography covering a range of about two thousand psig. Initial analysis of the data shows a significant aperture closure with increase in effective confining stress. Visual and detailed descriptions of the process are shown in the report. Both extensional and shear fractures have been considered. A series of water imbibition tests were conducted in which water was injected into a fracture and its migration into the matrix was monitored with CT and DR x-ray techniques. The objective was to understand the impact of the fracture, its topology and occupancy on the nature of mass transfer between the matrix and the fracture. Counter-current imbibition next to the fracture was observed and quantified, including the influence of formation layering. A group of Shear fractures were studied, with layers perpendicular and parallel to the main axis of the sample. The structures of the fractures as well as their impact on absolute permeability and on oil displacement by water were evaluated. Shear fractures perpendicular to the layers lead to a wide distribution of pores and to an overall increase in absolute permeability. Shear fractures parallel to the layers lead to an overall increase in absolute permeability, but a decrease in displacement efficiency. This DoE project funded or partially funded three Ph.D. and four M.Sc. students at the Pennsylvania State University. The results from the research have yielded several abstracts, presentations and papers. Much of the work is still in the process of being published.

A.S. Grader; D. Elsworth; P.M. Halleck; F. Alvarao; A. Alajmi; Z. Karpyn; N. Mohammed; S. Al-Enezi

2005-12-07T23:59:59.000Z

56

Hydraulic Fracturing (Vermont)  

Broader source: Energy.gov [DOE]

Vermont prohibits hydraulic fracturing or the collection, storage, or treatment of wastewater from hydraulic fracturing

57

Fracturing pressures and near-well fracture geometry of arbitrarily oriented and horizontal wells  

SciTech Connect (OSTI)

The hydraulic fracturing of arbitrarily oriented and horizontal wells is made challenging by the far more complicated near-well fracture geometry compared to that of conventional vertical wells. This geometry is important both for hydraulic fracture propagation and the subsequent post-treatment well performance. Fracture tortuosity of arbitrarily oriented and horizontal wells is likely to cause large initiation pressures and reduction in the fracture widths. This paper presents a comprehensive study of the effects of important variables, including the principal stresses, wellbore orientation, and perforation configuration on fracture geometry. Initiation pressures, the contact between arbitrarily oriented wells and the fracture plane, and the near-well fracture geometry are determined and discussed. This study also shows that because of the near-well stress concentration the fracture width at the wellbore is always smaller than the maximum fracture width. This can have important consequences during hydraulic fracturing.

Chen, Z.; Economides, M.J.

1995-12-31T23:59:59.000Z

58

Use of Tracers to Characterize Fractures in Engineered Geothermal...  

Broader source: Energy.gov (indexed) [DOE]

define the subsurface system of fractures and mapping of fluid flow. * limited fracture detection capability * lack of high-temperature monitoring tools and sensors *...

59

Fracture Evolution Following a Hydraulic Stimulation within an...  

Broader source: Energy.gov (indexed) [DOE]

define the subsurface system of fractures and mapping of fluid flow. * limited fracture detection capability * lack of high-temperature monitoring tools and sensors *...

60

A Fracture Criterion for the Notch Strength of High Strength Steels in the Presence of Hydrogen  

E-Print Network [OSTI]

that the presence of lattice hydrogen increases the susceptibility to hydrogen embrittlement whereas trapped. Keywords: Hydrogen embrittlement, Hydrogen trapping, Weakest link statistics. 1. Introduction Steels, when failure. Consequently, the adverse effects of hydrogen embrittlement must be included in engineer- ing

Fleck, Norman A.

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Optimizing fracture stimulation using treatment-well tiltmeters and integrated fracture modeling  

SciTech Connect (OSTI)

This paper covers the optimization of hydraulic fracture treatments in a new coalbed methane (CBM) reservoir in Wyoming. A multiwell pilot project was conducted in the Copper Ridge (CR) field to assess future development potential. Hydraulic fracture mapping was successfully performed with treatment-well tiltmeters on six wells including the first-ever used on propped treatments. The mapped fracture height was then used to calibrate the fracture model, perform on-site fracture-design changes, and optimize future fracture treatments. This paper shows how early use of fracture diagnostics can assist in the development of a new reservoir.

Mayerhofer, M.; Stutz, L.; Davis, E.; Wolhart, S. [Pinnacle Technology Houston, Houston, TX (United States)

2006-05-15T23:59:59.000Z

62

Hydraulic fracturing in a naturally fractured reservoir  

SciTech Connect (OSTI)

Hydraulic fracturing of wells in naturally fractured reservoirs can differ dramatically from fracturing wells in conventional isotropic reservoirs. Fluid leakoff is the primary difference. In conventional reservoirs, fluid leakoff is controlled by reservoir matrix and fracture fluid parameters. The fluid leakoff rate in naturally fractured reservoirs is typically excessive and completely dominated by the natural fractures. This paper presents several field examples of a fracture stimulation program performed on the naturally fractured Devonia carbonate of West Texas. Qualitative pressure decline analysis and net treating pressure interpretation techniques were utilized to evaluate the existence of natural fractures in the Devonian Formation. Quantitative techniques were utilized to assess the importance of the natural fractures to the fracturing process. This paper demonstrates that bottomhole pressure monitoring of fracture stimulations has benefits over conducting minifrac treatments in naturally fractured reservoirs. Finally, the results of this evaluation were used to redesign fracture treatments to ensure maximum productivity and minimize costs.

Britt, L.K.; Hager, C.J.; Thompson, J.W.

1994-12-31T23:59:59.000Z

63

Power mixture and green body for producing silicon nitride base & articles of high fracture toughness and strength  

DOE Patents [OSTI]

A powder mixture and a green body for producing a silicon nitride-based article of improved fracture toughness and strength. The powder mixture includes 9a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon mitride powder of an average particle size of about 0.2 .mu.m and a surface area of about 8-12m.sup.2 g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 .mu.m and a surface area of about 2-4 m.sup.2 /g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified articel an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. The green body is formed from the powder mixture, an effective amount of a suitable oxide densification aid, and an effective amount of a suitable organic binder.

Huckabee, Marvin L. (Marlboro, MA); Buljan, Sergej-Tomislav (Acton, MA); Neil, Jeffrey T. (Acton, MA)

1991-01-01T23:59:59.000Z

64

Power mixture and green body for producing silicon nitride base articles of high fracture toughness and strength  

DOE Patents [OSTI]

A powder mixture and a green body for producing a silicon nitride-based article of improved fracture toughness and strength are disclosed. The powder mixture includes (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 [mu]m and a surface area of about 8-12m[sup 2]g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 [mu]m and a surface area of about 2-4 m[sup 2]/g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. The green body is formed from the powder mixture, an effective amount of a suitable oxide densification aid, and an effective amount of a suitable organic binder. No Drawings

Huckabee, M.L.; Buljan, S.T.; Neil, J.T.

1991-09-17T23:59:59.000Z

65

Fracture of aluminum naval structures  

E-Print Network [OSTI]

Structural catastrophic failure of naval vessels due to extreme loads such as underwater or air explosion, high velocity impact (torpedoes), or hydrodynamic loads (high speed vessels) is primarily caused by fracture. ...

Galanis, Konstantinos, 1970-

2007-01-01T23:59:59.000Z

66

An analysis of tensile strength, fracture initiation and propagation in anisotropic rock (gas shale) using Brazilian tests equipped with high speed video and acoustic emission.  

E-Print Network [OSTI]

?? This study attempts to further our knowledge of fracture behaviour by establishing an experimental system that links tensile strength, fracture initiation and propagation of… (more)

Simpson, Nathaniel Denis John

2013-01-01T23:59:59.000Z

67

MULTI-ATTRIBUTE SEISMIC/ROCK PHYSICS APPROACH TO CHARACTERIZING FRACTURED RESERVOIRS  

SciTech Connect (OSTI)

This project consists of three key interrelated Phases, each focusing on the central issue of imaging and quantifying fractured reservoirs, through improved integration of the principles of rock physics, geology, and seismic wave propagation. This report summarizes the results of Phase I of the project. The key to successful development of low permeability reservoirs lies in reliably characterizing fractures. Fractures play a crucial role in controlling almost all of the fluid transport in tight reservoirs. Current seismic methods to characterize fractures depend on various anisotropic wave propagation signatures that can arise from aligned fractures. We are pursuing an integrated study that relates to high-resolution seismic images of natural fractures to the rock parameters that control the storage and mobility of fluids. Our goal is to go beyond the current state-of-the art to develop and demonstrate next generation methodologies for detecting and quantitatively characterizing fracture zones using seismic measurements. Our study incorporates 3 key elements: (1) Theoretical rock physics studies of the anisotropic viscoelastic signatures of fractured rocks, including up scaling analysis and rock-fluid interactions to define the factors relating fractures in the lab and in the field. (2) Modeling of optimal seismic attributes, including offset and azimuth dependence of travel time, amplitude, impedance and spectral signatures of anisotropic fractured rocks. We will quantify the information content of combinations of seismic attributes, and the impact of multi-attribute analyses in reducing uncertainty in fracture interpretations. (3) Integration and interpretation of seismic, well log, and laboratory data, incorporating field geologic fracture characterization and the theoretical results of items 1 and 2 above. The focal point for this project is the demonstration of these methodologies in the Marathon Oil Company Yates Field in West Texas.

Gary Mavko

2000-10-01T23:59:59.000Z

68

theoretical and applied fracture  

E-Print Network [OSTI]

theoretical and applied fracture mechanics ELSEVIER Theoretical and Applied Fracture Mechanics 00 and Applied Fracture Mechanics 00 (1995) 000-000 Recently, some European countries developed defect specific. A suitable probabilistic fracture mechanic

Cizelj, Leon

69

Interferometric hydrofracture microseism localization using neighboring fracture  

E-Print Network [OSTI]

Interferometric hydrofracture microseism localization using neighboring fracture Oleg V. Poliannikov1 , Alison E. Malcolm1 , Hugues Djikpesse2 , and Michael Prange2 ABSTRACT Hydraulic fracturing is the process of injecting high-pressure fluids into a reservoir to induce fractures and thus improve reservoir

Malcolm, Alison

70

Test plan: Sealing of the Disturbed Rock Zone (DRZ), including Marker Bed 139 (MB139) and the overlying halite, below the repository horizon, at the Waste Isolation Pilot Plant. [Cementitious grout into fractured WIPP rock  

SciTech Connect (OSTI)

This test plan describes activities intended to demonstrate equipment and techniques for producing, injecting, and evaluating microfine cementitious grout. The grout will be injected in fractured rock located below the repository horizon at the Waste Isolation Pilot Plant (WIPP). These data are intended to support the development of the Alcove Gas Barrier System (AGBS), the design of upcoming, large-scale seal tests, and ongoing laboratory evaluations of grouting efficacy. Degradation of the grout will be studied in experiments conducted in parallel with the underground grouting experiment.

Ahrens, E.H.

1992-05-01T23:59:59.000Z

71

Numerical Investigation of Interaction Between Hydraulic Fractures and Natural Fractures  

E-Print Network [OSTI]

Hydraulic fracturing of a naturally-fractured reservoir is a challenge for industry, as fractures can have complex growth patterns when propagating in systems of natural fractures in the reservoir. Fracture propagation near a natural fracture (NF...

Xue, Wenxu

2011-02-22T23:59:59.000Z

72

Comminution of solids caused by kinetic energy of high shear strain rate, with implications for impact, shock, and shale fracturing  

Science Journals Connector (OSTI)

...Discussion Although a practically most intriguing application of dynamic comminution modeling may be the fracturing of gas or oil shale by electro-hydraulic pulsed arc (15, 16) or by chemical explosion in the pipe of a horizontal borehole, no data...

Zden?k P. Bažant; Ferhun C. Caner

2013-01-01T23:59:59.000Z

73

Regional Analysis And Characterization Of Fractured Aquifers...  

Open Energy Info (EERE)

geothermal applications include the recognition of and exploration for deep fracture permeability in crystalline rocks. It is well known that the best currently available...

74

Parametric study of an efficient renewable power-to-substitute-natural-gas process including high-temperature steam electrolysis  

Science Journals Connector (OSTI)

Abstract Power-to-Substitute Natural Gas processes are investigated to offer solutions for renewable energy storing or transportation. In the present study, an original Power-to-SNG process combining high-temperature steam electrolysis and CO2 methanation is implemented and simulated. A reference process is firstly defined, including a specific modelling approach of the electrolysis and a methanation modelling including a kinetic law. The process also integrates a unit to clean the gas from residual CO2, H2 and H2O for gas network injection. Having set all the units, simulations are performed with ProsimPlus 3™ software for a reference case where the electrolyser and the methanation reactors are designed. The reference case allows to produce 67.5 Nm3/h of SNG with an electrical energy consumption of 14.4 kW h/Nm3. The produced SNG satisfies specifications required for network injection. From this reference process, two sensitivity analyses on electrolysis and methanation working points and on external parameters and constraints are considered. As a main result, we observe that the reference case maximises both process efficiency and SNG production when compared with other studied cases.

Myriam De Saint Jean; Pierre Baurens; Chakib Bouallou

2014-01-01T23:59:59.000Z

75

Reviving Abandoned Reservoirs with High-Pressure Air Injection: Application in a Fractured and Karsted Dolomite Reservoir  

SciTech Connect (OSTI)

Despite declining production rates, existing reservoirs in the United States contain vast volumes of remaining oil that is not being effectively recovered. This oil resource constitutes a huge target for the development and application of modern, cost-effective technologies for producing oil. Chief among the barriers to the recovery of this oil are the high costs of designing and implementing conventional advanced recovery technologies in these mature, in many cases pressure-depleted, reservoirs. An additional, increasingly significant barrier is the lack of vital technical expertise necessary for the application of these technologies. This lack of expertise is especially notable among the small operators and independents that operate many of these mature, yet oil-rich, reservoirs. We addressed these barriers to more effective oil recovery by developing, testing, applying, and documenting an innovative technology that can be used by even the smallest operator to significantly increase the flow of oil from mature U.S. reservoirs. The Bureau of Economic Geology and Goldrus Producing Company assembled a multidisciplinary team of geoscientists and engineers to evaluate the applicability of high-pressure air injection (HPAI) in revitalizing a nearly abandoned carbonate reservoir in the Permian Basin of West Texas. The Permian Basin, the largest oil-bearing basin in North America, contains more than 70 billion barrels of remaining oil in place and is an ideal venue to validate this technology. We have demonstrated the potential of HPAI for oil-recovery improvement in preliminary laboratory tests and a reservoir pilot project. To more completely test the technology, this project emphasized detailed characterization of reservoir properties, which were integrated to access the effectiveness and economics of HPAI. The characterization phase of the project utilized geoscientists and petroleum engineers from the Bureau of Economic Geology and the Department of Petroleum Engineering (both at The University of Texas at Austin) to define the controls on fluid flow in the reservoir as a basis for developing a reservoir model. The successful development of HPAI technology has tremendous potential for increasing the flow of oil from deep carbonate reservoirs in the Permian Basin, a target resource that can be conservatively estimated at more than 1.5 billion barrels. Successful implementation in the field chosen for demonstration, for example, could result in the recovery of more than 34 million barrels of oil that will not otherwise be produced. Geological and petrophysical analysis of available data at Barnhart field reveals the following important observations: (1) the Barnhart Ellenburger reservoir is similar to most other Ellenburger reservoirs in terms of depositional facies, diagenesis, and petrophysical attributes; (2) the reservoir is characterized by low to moderate matrix porosity much like most other Ellenburger reservoirs in the Permian Basin; (3) karst processes (cave formation, infill, and collapse) have substantially altered stratigraphic architecture and reservoir properties; (4) porosity and permeability increase with depth and may be associated with the degree of karst-related diagenesis; (5) tectonic fractures overprint the reservoir, improving overall connectivity; (6) oil-saturation profiles show that the oil-water contact (OWC) is as much as 125 ft lower than previous estimations; (7) production history and trends suggest that this reservoir is very similar to other solution-gas-drive reservoirs in the Permian Basin; and (8) reservoir simulation study showed that the Barnhart reservoir is a good candidate for HPAI and that application of horizontal-well technology can improve ultimate resource recovery from the reservoir.

Robert Loucks; Stephen C. Ruppel; Dembla Dhiraj; Julia Gale; Jon Holder; Jeff Kane; Jon Olson; John A. Jackson; Katherine G. Jackson

2006-09-30T23:59:59.000Z

76

Determination of the fracture parameters associated with mixed mode displacement fields and applications of high density geometric moire  

E-Print Network [OSTI]

conducted on both PMMA and aluminum. The analyses of the finite element models indicated that the algorithm developed could be used to determine the opening and shear mode fracture parameters, without being affected by the rigid body rotation... 89 92 C PROCEDURE FOR REPRODUCING 80 LINE/MM GRATINGS . 95 D BONDING THE FILM GRATINGS TO THE TEST SPECIMEN 100 PMMA Aluminum 6061-T6511 E USE OF FILM GRATINGS IN GEOMETRIC MOIRE. . . F USING THE EPIX DIGITAL IMAGING SYSTEM, V2. 6 Set...

Kmiec, Kenneth James

1994-01-01T23:59:59.000Z

77

Fracture Properties From Seismic Scattering  

E-Print Network [OSTI]

Fractures scatter seismic energy and this energy can be analyzed to provide information about fracture

Burns, Daniel R.

2007-01-01T23:59:59.000Z

78

Seismic characterization of fractures  

E-Print Network [OSTI]

Seismic characterization of fractures. José M. Carcione, OGS, Italy. Fractured geological formations are generally represented with a stress-strain relation.

JM Carcione

2014-06-07T23:59:59.000Z

79

Multiphase Flow in Geometrically Simple Fracture Intersections  

SciTech Connect (OSTI)

A two-dimensional lattice Boltzmann (LB) model with fluid-fluid and solid-fluid interaction potentials was used to Study gravity-driven flow in geometrically simple fracture intersections. simulated scenarios included fluid dripping from a fracture aperture, two-phase flow through intersecting fractures and thin-filin flow oil smooth and undulating solid surfaces. Qualitative comparisons with recently published experimental findings indicate that for these scenarios the LB model captured the underlying physics reasonably well.

Hakan Basagaoglu; Paul Meakin; Sauro Succi; Timothy R. Ginn

2006-03-01T23:59:59.000Z

80

Multiphase flow in geometrically simple fracture intersection  

SciTech Connect (OSTI)

A two-dimensional lattice Boltzmann (LB) model with fluid-fluid and solid-fluid interaction potentials was used to study gravity-driven flow in geometrically simple fracture intersections. Simulated scenarios included fluid dripping from a fracture aperture, two-phse flow through intersecting fractures, and thin-film flow on smooth and undulating solid surfaces. Qualititative comparisons with recently published experimental findings indicate that for these scenarios the LB model captured the underlying physics reasonably well.

H. Basagaoglu; P. Meakin; M. Mathew

2006-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Nanocomposites for ultra high density information storage, devices including the same, and methods of making the same  

DOE Patents [OSTI]

A nanocomposite article that includes a single-crystal or single-crystal-like substrate and heteroepitaxial, phase-separated layer supported by a surface of the substrate and a method of making the same are described. The heteroepitaxial layer can include a continuous, non-magnetic, crystalline, matrix phase, and an ordered, magnetic magnetic phase disposed within the matrix phase. The ordered magnetic phase can include a plurality of self-assembled crystalline nanostructures of a magnetic material. The phase-separated layer and the single crystal substrate can be separated by a buffer layer. An electronic storage device that includes a read-write head and a nanocomposite article with a data storage density of 0.75 Tb/in.sup.2 is also described.

Goyal, Amit; Shin, Junsoo

2014-04-01T23:59:59.000Z

82

Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Hydrogen-Assisted Fracture: Materials Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture Brian Somerday, Chris San Marchi, and Dorian Balch Sandia National Laboratories Livermore, CA Hydrogen Pipeline Working Group Workshop Augusta, GA August 30-31, 2005 SNL has 40+ years experience with effects of high-pressure hydrogen gas on materials * Design and maintenance of welded stainless steel pressure vessels for containment of high-pressure H 2 isotopes - Extensive testing of stainless steels exposed to high-pressure H 2 gas * Six-year program in 1970s focused on feasibility of using natural gas pipeline network for H 2 gas - Materials testing in high-pressure H 2 gas using laboratory specimens and model pipeline - Examined fusion zone and heat affected zones of welds * Active SNL staff have authored 70+ papers and organized 6

83

Imaging Hydraulic Fractures: Source Location Uncertainty Analysis At The UPRC Carthage Test Site  

E-Print Network [OSTI]

Hydraulic fracturing is a useful tool for enhancing gas and oil production. High-resolution seismic imaging of the fracture geometry and fracture growth process is the key in determining optimal spacing and location of ...

Li, Yingping

1996-01-01T23:59:59.000Z

84

Coordinated studies in support of hydraulic fracturing of coalbed methane. Annual report, June 1990-October 1991  

SciTech Connect (OSTI)

The production of natural gas coal typically requires stimulation in the form of hydraulic fracturing. The results of hydraulic fracturing treatments have ranged from highly successful to less than satisfactory. The approach in the work has been to experimentally evaluate parameters that pertain to coal fluid interactions during hydraulic fracturing and post-frac production and then apply the findings to the selection of fracturing fluids and treatment design. Evaluated parameters include leakoff through cleats, pressure drops through cleated slots with slurries, proppant transport, conductivity, and coal matrix damage due to fracturing fluids. Some conclusions from the work include (1) 100 mesh sand alone can control leakoff through cleats; (2) coal faces alone do not increase pressure drop through fractures with slurries; (3) restrictions approaching 2 proppant diameters are required to see pressure increases; (4) borate fluid pH's of 9.5 are required for transport; (5) mixed proppant conductivities of 100 mesh and 16/30 can be 50% lower than the larger proppant; (6) guar based fracturing fluids can cause up to 90% permeability damage to the coal matrix; (7) HEC containing foams provide the best cleanup in the laboratory (only 10 to 30% damage and have shown excellent results in field trials); and (8) expanded use of COMPAS is recommended to document field results.

Penny, G.S.; Conway, M.W.

1992-04-01T23:59:59.000Z

85

Fracture-Flow-Enhanced Solute Diffusion into Fractured Rock  

E-Print Network [OSTI]

influence of effective fracture aperture, Water Resourcesa system of parallel fractures, Water Resources Research,solutions for a single fractures, Water Resources Research,

Wu, Yu-Shu; Ye, Ming; Sudicky, E.A.

2008-01-01T23:59:59.000Z

86

Evaluate the fracture and fatigue resistances of hot mix asphalt containing high percentage reclaimed asphalt pavement (RAP) materials at low and intermediate temperatures.  

E-Print Network [OSTI]

??When applying recycled asphalt technology in a flexible pavement project, most of the concerns are related to low-temperature fracture and fatigue cracking, since the stiffness… (more)

Tang, Sheng

2014-01-01T23:59:59.000Z

87

Notch Sensitivity of Ceramic Composites with Rising Fracture Resistance  

E-Print Network [OSTI]

of common notched test configurations with the material's fracture resistance. Analogous treatments of notch sensitivity have been used previously for other materials that exhibit rising fracture resistance, includingNotch Sensitivity of Ceramic Composites with Rising Fracture Resistance Michael A. Mattoni

Zok, Frank

88

HYDRAULIC STIMULATION OF NATURAL FRACTURES AS REVEALED BY INDUCED MICROEARTHQUAKES,  

E-Print Network [OSTI]

-1- HYDRAULIC STIMULATION OF NATURAL FRACTURES AS REVEALED BY INDUCED MICROEARTHQUAKES, CARTHAGE, December, 2001 Manuscript # 01066 LAUR# 01-1204 #12;Hydraulic Stimulation of Natural Fractures -2- ABSTRACT We have produced a high-resolution microseismic image of a hydraulic fracture stimulation

89

Fracture and hydrology data from field studies at Stripa, Sweden  

SciTech Connect (OSTI)

The purpose of this report is to present the basic fracture and hydrology data collected as part of the joint LBL-KBS fracture hydrology program at Stripa, Sweden. A detailed description of the fracture-core logging and hydrology borehole testing procedures is included as well as a description of how the fracture and hydrology data were coded and organized. Based on this coding a series of computer data files for the fracture and hydrology borehole data have been constructed and these are described in detail. The fracture data file for one borehole is presented as an example in an appendix along with all of the raw and some partially processed and analyzed fracture hydrology data files. A detailed description of how this data will be analyzed to develop a thorough understanding of the fracture system and hydrogeologic characteristics of the Stripa site is presented.

Gale, J.E.

1981-04-01T23:59:59.000Z

90

Anomalous transport through porous and fractured media  

E-Print Network [OSTI]

Anomalous transport, understood as the nonlinear scaling with time of the mean square displacement of transported particles, is observed in many physical processes, including contaminant transport through porous and fractured ...

Kang, Peter Kyungchul

2014-01-01T23:59:59.000Z

91

Hydraulic Fracturing Simulation of Complex Fractures Growth in Naturally Fractured Shale Gas Reservoir  

Science Journals Connector (OSTI)

Hydraulic fracturing is regarded as one of the essential techniques for developing shale reservoirs at present. During fracturing, propagation of multi-fractures and complex fracture network is developed as re...

Wang Song; Zhao Jinzhou; Li Yongming

2014-10-01T23:59:59.000Z

92

The Political History of Hydraulic Fracturing’s Expansion Across the West  

E-Print Network [OSTI]

Political History of Hydraulic Fracturing’s Expansion AcrossPolitical History of Hydraulic Fracturing’s Expansion Acrosss use of the hydraulic fracturing development process.

Forbis, Robert E.

2014-01-01T23:59:59.000Z

93

Self-potential observations during hydraulic fracturing  

E-Print Network [OSTI]

potential measurements during hydraulic fracturing of BunterMonitoring during hydraulic fracturing using the TG-2 well,fracture processes in hydraulic fracturing, Quarterly Report

Moore, J R; Glaser, Steven D

2007-01-01T23:59:59.000Z

94

Self-potential observations during hydraulic fracturing  

E-Print Network [OSTI]

potential measurements during hydraulic fracturing of BunterMonitoring during hydraulic fracturing using the TG-2 well,fracture processes in hydraulic fracturing, Quarterly Report

Moore, Jeffrey R.; Glaser, Steven D.

2008-01-01T23:59:59.000Z

95

Hydraulic fracture mechanism in unconsolidated formations.  

E-Print Network [OSTI]

??Most models developed for hydraulic fracturing in unconsolidated sands are based on Linear Elastic Fracture Mechanics (LEFM) and tensile fracture (Mode I fracture). However, in… (more)

Hosseini, Seyed Mehran

2012-01-01T23:59:59.000Z

96

Testing sand used in hydraulic fracturing operations  

SciTech Connect (OSTI)

Recommended practices for testing sand used in hydraulic fracturing operations are outlined as developed by the Task Group on Evaluation of Hydraulic Fracturing Sand under the API Subcommittee on Evaluation of Well Completion Materials. The tests recommended were developed to improve the quality of frac sand delivered to the well site, and are for use in evaluating certain physical properties of sand used in hydraulic fracturing operations. The tests suggested enable users to compare physical characteristics of various sands and to select materials most useful for such applications. Parameters to be tested include turbidity, clay and soft particle content, crush resistance, and mineralogic analysis.

Not Available

1983-03-01T23:59:59.000Z

97

Self-potential observations during hydraulic fracturing  

SciTech Connect (OSTI)

The self-potential (SP) response during hydraulic fracturing of intact Sierra granite was investigated in the laboratory. Excellent correlation of pressure drop and SP suggests that the SP response is created primarily by electrokinetic coupling. For low pressures, the variation of SP with pressure drop is linear, indicating a constant coupling coefficient (Cc) of -200 mV/MPa. However for pressure drops >2 MPa, the magnitude of the Cc increases by 80% in an exponential trend. This increasing Cc is related to increasing permeability at high pore pressures caused by dilatancy of micro-cracks, and is explained by a decrease in the hydraulic tortuosity. Resistivity measurements reveal a decrease of 2% prior to hydraulic fracturing and a decrease of {approx}35% after fracturing. An asymmetric spatial SP response created by injectate diffusion into dilatant zones is observed prior to hydraulic fracturing, and in most cases this SP variation revealed the impending crack geometry seconds before failure. At rupture, injectate rushes into the new fracture area where the zeta potential is different than in the rock porosity, and an anomalous SP spike is observed. After fracturing, the spatial SP distribution reveals the direction of fracture propagation. Finally, during tensile cracking in a point load device with no water flow, a SP spike is observed that is caused by contact electrification. However, the time constant of this event is much less than that for transients observed during hydraulic fracturing, suggesting that SP created solely from material fracture does not contribute to the SP response during hydraulic fracturing.

Moore, Jeffrey R.; Glaser, Steven D.

2007-09-13T23:59:59.000Z

98

Evaluation of naturally fractured gas shale production utilizing multiwell transient tests: A field study  

SciTech Connect (OSTI)

A series of multiple well transient tests were conducted in a Devonian shale gas field in Meigs County, Ohio. Production parameters were quantified and it was determined that the reservoir is highly anisotropic, which is a significant factor in calculating half-fracture length from pressure transient data. Three stimulation treatments, including conventional explosive shooting, nitrogen foam frac, and high energy gas frac (HEGF), were compared on the basis of overall effectiveness and performance. Based on the evaluation of results, the nitrogen foam frac provided the most improved productivity. The study provided new type curves and analytical solutions for the mathematical representation of naturally fractured reservoirs and confirmed that the shale reservoir in Meigs County can be modeled as a dual porosity system using pseudosteady-state gas transfer from the matrix to the fracture system.

Chen, C.C.; Alam, J.; Blanton, T.L.; Vozniak, J.P.

1984-05-01T23:59:59.000Z

99

Simulation of Hydraulic Fractures and their Interactions with Natural Fractures  

E-Print Network [OSTI]

Modeling the stimulated reservoir volume during hydraulic fracturing is important to geothermal and petroleum reservoir stimulation. The interaction between a hydraulic fracture and pre-existing natural fractures exerts significant control...

Sesetty, Varahanaresh

2012-10-19T23:59:59.000Z

100

Fracture characterization from attenuation of Stoneley waves across a fracture  

E-Print Network [OSTI]

Fractures contribute significantly to the permeability of a formation. It is important to understand the fracture distribution and fluid transmissivity. Though traditional well logs can image fractures intersecting the ...

Bakku, Sudhish Kumar

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Characterization of Fractures in Geothermal Reservoirs Using Resistivity |  

Open Energy Info (EERE)

Characterization of Fractures in Geothermal Reservoirs Using Resistivity Characterization of Fractures in Geothermal Reservoirs Using Resistivity Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Characterization of Fractures in Geothermal Reservoirs Using Resistivity Abstract The optimal design of production in fractured geothermal reservoirs requires knowledge of the resource's connectivity, therefore making fracture characterization highly important. This study aims to develop methodologies to use resistivity measurements to infer fracture properties in geothermal fields. The resistivity distribution in the field can be estimated by measuring potential differences between various points and the data can then be used to infer fracture properties due to the contrast in resistivity between water and rock.

102

TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES...  

Open Energy Info (EERE)

TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES IN THE COSO GEOTHERMAL FIELD FROM ANALYSES OF SHEAR-WAVE SPLITTING Jump to: navigation, search OpenEI Reference...

103

A Rare Isolated Trapezoid Fracture  

E-Print Network [OSTI]

wrist in suggested scaphoid fracture. Acta Radiol. 1988;29:Rare isolated trapezoid fracture: a case report. Hand. 2008;suspect and diagnose this fracture. 2,8 REFERENCES 1. Papp

Afifi, Negean; Lu, Jenny J

2011-01-01T23:59:59.000Z

104

Influence of rock mass fracturing on the net penetration rates of hard rock \\{TBMs\\}  

Science Journals Connector (OSTI)

Abstract Penetration rates during excavation using hard rock tunnel boring machines (TBMs) are significantly influenced by the degree of fracturing of the rock mass. In the NTNU prediction model for hard rock TBM performance and costs, the rock mass fracturing factor (ks) is used to include the influence of rock mass fractures. The rock mass fracturing factor depends on the degree of fracturing, fracture type, fracture spacing, and the angle between fracture systems and the tunnel axis. In order to validate the relationship between the degree of fracturing and the net penetration rate of hard rock TBMs, field work has been carried out, consisting of geological back-mapping and analysis of performance data from a TBM tunnel. The rock mass influence on hard rock TBM performance prediction is taken into account in the NTNU model. Different correlations between net penetration rate and the fracturing factor (ks) have been identified for a variety of ks values.

F.J. Macias; P.D. Jakobsen; Y. Seo; A. Bruland

2014-01-01T23:59:59.000Z

105

Multiphase Fluid Flow in Deformable Variable-Aperture Fractures - Final Report  

SciTech Connect (OSTI)

Fractures provide flow paths that can potentially lead to fast migration of fluids or contaminants. A number of energy-­?related applications involve fluid injections that significantly perturb both the pressures and chemical composition of subsurface fluids. These perturbations can cause both mechanical deformation and chemical alteration of host rocks with potential for significant changes in permeability. In fractured rock subjected to coupled chemical and mechanical stresses, it can be difficult to predict the sign of permeability changes, let alone the magnitude. This project integrated experimental and computational studies to improve mechanistic understanding of these coupled processes and develop and test predictive models and monitoring techniques. The project involved three major components: (1) study of two-­?phase flow processes involving mass transfer between phases and dissolution of minerals along fracture surfaces (Detwiler et al., 2009; Detwiler, 2010); (2) study of fracture dissolution in fractures subjected to normal stresses using experimental techniques (Ameli, et al., 2013; Elkhoury et al., 2013; Elkhoury et al., 2014) and newly developed computational models (Ameli, et al., 2014); (3) evaluation of electrical resistivity tomography (ERT) as a method to detect and quantify gas leakage through a fractured caprock (Breen et al., 2012; Lochbuhler et al., 2014). The project provided support for one PhD student (Dr. Pasha Ameli; 2009-­?2013) and partially supported a post-­?doctoral scholar (Dr. Jean Elkhoury; 2010-­?2013). In addition, the project provided supplemental funding to support collaboration with Dr. Charles Carrigan at Lawrence Livermore National Laboratory in connection with (3) and supported one MS student (Stephen Breen; 2011-­?2013). Major results from each component of the project include the following: (1) Mineral dissolution in fractures occupied by two fluid phases (e.g., oil-­?water or water-­?CO{sub 2}) causes changes in local capillary forces and redistribution of fluids. These coupled processes enhance channel formation and the potential for development of fast flow paths through fractures. (2) Dissolution in fractures subjected to normal stress can result in behaviors ranging from development of dissolution channels and rapid permeability increases to fracture healing and significant permeability decreases. The timescales associated with advective transport of dissolved ions in the fracture, mineral dissolution rates, and diffusion within the adjacent porous matrix dictate the sign and magnitude of the resulting permeability changes. Furthermore, a high-­? resolution mechanistic model that couples elastic deformation of contacts and aperture-­?dependent dissolution rates predicts the range of observed behaviors reasonably well. (3) ERT has potential as a tool for monitoring gas leakage in deep formations. Using probabilistic inversion methods further enhances the results by providing uncertainty estimates of inverted parameters.

Detwiler, Russell

2014-04-30T23:59:59.000Z

106

Fracture Processes Observed with A Cryogenic Detector  

E-Print Network [OSTI]

In the early stages of running of the CRESST dark matter search using sapphire detectors at very low temperature, an unexpectedly high rate of signal pulses appeared. Their origin was finally traced to fracture events in the sapphire due to the very tight clamping of the detectors. During extensive runs the energy and time of each event was recorded, providing large data sets for such phenomena. We believe this is the first time the energy release in fracture has been directly and accurately measured on a microscopic event-by-event basis. The energy threshold corresponds to the breaking of only a few hundred covalent bonds, a sensitivity some orders of magnitude greater than that of previous technique. We report some features of the data, including energy distributions, waiting time distributions, autocorrelations and the Hurst exponent. The energy distribution appear to follow a power law, $dN/dE\\propto E^{-\\beta}$, similar to the power law for earthquake magnitudes, and after appropriate translation, with a similar exponent. In the time domain,the waiting time $w$ or gap distribution between events has a power law behavior at small $w$ and an exponential fall-off at large $w,$ and can be fit $\\propto w^{-\\alpha}e^{-w/w_0}$. The autocorrelation function shows time correlations lasting for substantial parts of an hour. An asymmetry is found around large events, with higher count rates after, as opposed to before,the large event .

J. Astrom; P. C. F. Di Stefano; F. Proebst; L. Stodolsky; J. Timonen; C. Bucci; S. Cooper; C. Cozzini; F. v. Feilitzsch; H. Kraus; J. Marchese; O. Meier; U. Nagel; Y. Ramachers; W. Seidel; M. Sisti; S. Uchaikin; L. Zerle

2006-03-21T23:59:59.000Z

107

Hydraulic Fracturing in Particulate Materials.  

E-Print Network [OSTI]

??For more than five decades, hydraulic fracturing has been widely used to enhance oil and gas production. Hydraulic fracturing in solid materials (e.g., rock) has… (more)

Chang, Hong

2004-01-01T23:59:59.000Z

108

Investigation of materials performances in high moisture environments including corrosive contaminants typical of those arising by using alternative fuels in gas turbines  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

materials performances in high moisture materials performances in high moisture environments including corrosive contaminants typical of those arising by using alternative fuels in gas turbines Gerald Meier, Frederick Pettit and Keeyoung Department of Materials Science and Engineering, Jung University of Pittsburgh Pittsburgh, PA 15260 Peer review Workshop III UTSR Project 04 01 SR116 October 18-20, 2005 Project Approach Task I Selection and Preparation of Specimens Task II Selection of Test Conditions Specimens : GTD111+CoNiCrAlY and Pt Aluminides, N5+Pt Aluminides Deposit : No Deposit, CaO, CaSO 4 , Na 2 SO 4 1150℃ Dry 1150℃ Wet 950℃ Wet 750℃ SO 3 950℃ Dry Selection of Test Temperature, T 1 , Gas Environment and Deposit Composition, D

109

Evaluation of the relationship between fracture conductivity, fracture fluid production, and effective fracture length  

E-Print Network [OSTI]

Low-permeability gas wells often produce less than predicted after a fracture treatment. One of the reasons for this is that fracture lengths calculated after stimulation are often less than designed lengths. While actual fracture lengths may...

Lolon, Elyezer P.

2006-04-12T23:59:59.000Z

110

High-temperature Pump Monitoring - High-temperature ESP Monitoring...  

Broader source: Energy.gov (indexed) [DOE]

Report Detecting Fractures Using Technology at High Temperatures and Depths - Geothermal Ultrasonic Fracture Imager (GUFI); 2010 Geothermal Technology Program Peer Review Report...

111

METHOD DEVELOPMENT FOR DETERMINING THE HYDRAULIC CONDUCTIVITY OF FRACTURED POROUS MEDIA  

SciTech Connect (OSTI)

Plausible, but unvalidated, theoretical model constructs for unsaturated hydraulic conductivity of fractured porous media are currently used in Performance Assessment (PA) modeling for cracked saltstone and concrete (Flach 2011). The Nuclear Regulatory Commission (NRC) has expressed concern about the lack of model support for these assumed Moisture Characteristic Curves (MCC) data, as noted in Requests for Additional Information (RAIs) PA-8 and SP-4 (Savannah River Remediation, LLC, 2011). The objective of this task was to advance PA model support by developing an experimental method for determining the hydraulic conductivity of fractured cementitious materials under unsaturated conditions, and to demonstrate the technique on fractured saltstone samples. The task was requested through Task Technical Request (TTR) HLW-SSF-TTR-2012-0016 and conducted in accordance with Task Technical & Quality Assurance Plan (TTQAP) SRNL-TR-2012-00090. Preliminary method development previously conducted by Kohn et al. (2012) identified transient outflow extraction as the most promising method for characterizing the unsaturated properties of fractured porous media. While the research conducted by Kohn et al. (2012) focused on fractured media analogs such as stacked glass slides, the current task focused directly on fractured saltstone. For this task, four sample types with differing fracture geometries were considered: 1) intact saltstone, 2) intact saltstone with a single saw cut, smooth surface fracture, 3) micro-fractured saltstone (induced by oven drying), and 4) micro-fractured saltstone with a single, fully-penetrating, rough-surface fracture. Each sample type was tested initially for saturated hydraulic conductivity following method ASTM D 5084 using a flexible wall permeameter. Samples were subsequently tested using the transient outflow extraction method to determine cumulative outflow as a function of time and applied pressure. Of the four sample types tested, two yielded datasets suitable for analysis (sample types 3 and 4). The intact saltstone sample (sample type 1) did not yield any measureable outflow over the pressure range of the outflow test (0-1000 cm H{sub 2}O). This was expected because the estimated air entry pressure for intact saltstone is on the order of 100,000 cm H{sub 2}O (Dixon et al., 2009). The intact saltstone sample with a single saw cut smooth surface fracture (sample type 2) did not produce useable data because the fracture completely drained at less than 10 cm H{sub 2}O applied pressure. The cumulative outflow data from sample types 3 and 4 were analyzed using an inverse solution of the Richard’s equation for water flow in variably saturated porous media. This technique was implemented using the computer code Hydrus-1D (Šim?nek et al., 2008) and the resulting output included the van Genuchten-Mualem water retention and relative permeability parameters and predicted saturated hydraulic conductivity (Van Genuchten, 1980; Van Genuchten et al., 1991). Estimations of relative permeability and saturated conductivity are possible because the transient response of the sample to pressure changes is recorded during the multi-step outflow extraction test. Characteristic curves were developed for sample types 3 and 4 based on the results of the transient outflow method and compared to that of intact saltstone previously reported by Dixon et al. (2009). The overall results of this study indicate that the outflow extraction method is suitable for measuring the hydraulic properties of micro-fractured porous media. The resulting cumulative outflow data can be analyzed using the computer code Hydrus-1D to generate the van Genuchten curve fitting parameters that adequately describe fracture drainage. The resulting characteristic curves are consistent with blended characteristic curves that combine the behaviors of low pressure drainage associated with fracture flow with high pressure drainage from the bulk saltstone matrix.

Dixon, K.

2013-09-30T23:59:59.000Z

112

A New Analytical Method to Quantify Residual Fluid Cleanup in Hydraulic Fractures  

E-Print Network [OSTI]

A number of factors contribute to reduce the production benefits from hydraulic fracturing, including inefficient fluid design, poor proppant selection and or, the inability of fracture fluid to degrade and flow back after treatment. Undegraded...

Zarrin, Tahira

2014-04-17T23:59:59.000Z

113

Flow focusing in unsaturated fracture networks: A numerical investigation  

SciTech Connect (OSTI)

A numerical modeling study is presented to investigate flow-focusing phenomena in a large-scale fracture network, constructed using field data collected from the unsaturated zone of Yucca Mountain, Nevada, the proposed repository site for high-level nuclear waste. The two-dimensional fracture network for an area of 100 m x 150 m contains more than 20,000 fractures. Steady-state unsaturated flow in the fracture network is investigated for different boundary conditions and rock properties. Simulation results indicate that flow paths are generally vertical, and that horizontal fractures mainly provide pathways between neighboring vertical paths. In addition to fracture properties, flow-focusing phenomena are also affected by rock-matrix permeability, with lower matrix permeability leading to a high degree of flow focusing. The simulation results further indicate that the average spacing between flow paths in a layered system tends to increase and flow tends to becomes more focused, with depth.

Zhang, Keni; Wu, Yu-Shu; Bodvarsson, G.S.; Liu, Hui-Hai

2003-04-17T23:59:59.000Z

114

Discrete Fracture Network Models for Risk Assessment of Carbon Sequestration in Coal  

SciTech Connect (OSTI)

A software package called DFNModeler has been developed to assess the potential risks associated with carbon sequestration in coal. Natural fractures provide the principal conduits for fluid flow in coal-bearing strata, and these fractures present the most tangible risks for the leakage of injected carbon dioxide. The objectives of this study were to develop discrete fracture network (DFN) modeling tools for risk assessment and to use these tools to assess risks in the Black Warrior Basin of Alabama, where coal-bearing strata have high potential for carbon sequestration and enhanced coalbed methane recovery. DFNModeler provides a user-friendly interface for the construction, visualization, and analysis of DFN models. DFNModeler employs an OpenGL graphics engine that enables real-time manipulation of DFN models. Analytical capabilities in DFNModeler include display of structural and hydrologic parameters, compartmentalization analysis, and fluid pathways analysis. DFN models can be exported to third-party software packages for flow modeling. DFN models were constructed to simulate fracturing in coal-bearing strata of the upper Pottsville Formation in the Black Warrior Basin. Outcrops and wireline cores were used to characterize fracture systems, which include joint systems, cleat systems, and fault-related shear fractures. DFN models were constructed to simulate jointing, cleating, faulting, and hydraulic fracturing. Analysis of DFN models indicates that strata-bound jointing compartmentalizes the Pottsville hydrologic system and helps protect shallow aquifers from injection operations at reservoir depth. Analysis of fault zones, however, suggests that faulting can facilitate cross-formational flow. For this reason, faults should be avoided when siting injection wells. DFN-based flow models constructed in TOUGH2 indicate that fracture aperture and connectivity are critical variables affecting the leakage of injected CO{sub 2} from coal. Highly transmissive joints near an injection well have potential to divert a large percentage of an injected CO{sub 2} stream away from a target coal seam. However, the strata-bound nature of Pottsville fracture systems is a natural factor that mitigates the risk of long-range leakage and surface seepage. Flow models indicate that cross-formational flow in strata-bound joint networks is low and is dissipated by about an order of magnitude at each successive bedding contact. These models help confirm that strata-bound joint networks are self-compartmentalizing and that the thick successions of interbedded shale and sandstone separating the Pottsville coal zones are confining units that protect shallow aquifers from injection operations at reservoir depth. DFN models are powerful tools for the simulation and analysis of fracture networks and can play an important role in the assessment of risks associated with carbon sequestration and enhanced coalbed methane recovery. Importantly, the stochastic nature DFN models dictates that they cannot be used to precisely reproduce reservoir conditions in a specific field area. Rather, these models are most useful for simulating the fundamental geometric and statistical properties of fracture networks. Because the specifics of fracture architecture in a given area can be uncertain, multiple realizations of DFN models and DFN-based flow models can help define variability that may be encountered during field operations. Using this type of approach, modelers can inform the risk assessment process by characterizing the types and variability of fracture architecture that may exist in geologic carbon sinks containing natural fractures.

Jack Pashin; Guohai Jin; Chunmiao Zheng; Song Chen; Marcella McIntyre

2008-07-01T23:59:59.000Z

115

Seismicity and Reservoir Fracture Characterization  

Broader source: Energy.gov [DOE]

Below are the project presentations and respective peer review results for Seismicity and Reservoir Fracture Characterization.

116

High Temperature Superconductors: From Delivery to Applications (Presentation from 2011 Ernest Orlando Lawrence Award-winner, Dr. Amit Goyal, and including introduction by Energy Secretary, Dr. Steven Chu)  

SciTech Connect (OSTI)

Dr. Amit Goyal, a high temperature superconductivity (HTS) researcher at Oak Ridge National Laboratory, was named a 2011 winner of the Department of Energy's Ernest Orlando Lawrence Award honoring U.S. scientists and engineers for exceptional contributions in research and development supporting DOE and its mission. Winner of the award in the inaugural category of Energy Science and Innovation, Dr. Goyal was cited for his work in 'pioneering research and transformative contributions to the field of applied high temperature superconductivity, including fundamental materials science advances and technical innovations enabling large-scale applications of these novel materials.' Following his basic research in grain-to-grain supercurrent transport, Dr. Goyal focused his energy in transitioning this fundamental understanding into cutting-edge technologies. Under OE sponsorship, Dr. Goyal co-invented the Rolling Assisted Bi-Axially Textured Substrate technology (RABiTS) that is used as a substrate for second generation HTS wires. OE support also led to the invention of Structural Single Crystal Faceted Fiber Substrate (SSIFFS) and the 3-D Self Assembly of Nanodot Columns. These inventions and associated R&D resulted in 7 R&D 100 Awards including the 2010 R&D Magazine's Innovator of the Year Award, 3 Federal Laboratory Consortium Excellence in Technology Transfer National Awards, a DOE Energy100 Award and many others. As a world authority on HTS materials, Dr. Goyal has presented OE-sponsored results in more than 150 invited talks, co-authored more than 350 papers and is a fellow of 7 professional societies.

Goyal, Amit (Oak Ridge National Laboratory) [Oak Ridge National Laboratory

2012-05-22T23:59:59.000Z

117

High Temperature Superconductors: From Delivery to Applications (Presentation from 2011 Ernest Orlando Lawrence Award-winner, Dr. Amit Goyal, and including introduction by Energy Secretary, Dr. Steven Chu)  

ScienceCinema (OSTI)

Dr. Amit Goyal, a high temperature superconductivity (HTS) researcher at Oak Ridge National Laboratory, was named a 2011 winner of the Department of Energy's Ernest Orlando Lawrence Award honoring U.S. scientists and engineers for exceptional contributions in research and development supporting DOE and its mission. Winner of the award in the inaugural category of Energy Science and Innovation, Dr. Goyal was cited for his work in 'pioneering research and transformative contributions to the field of applied high temperature superconductivity, including fundamental materials science advances and technical innovations enabling large-scale applications of these novel materials.' Following his basic research in grain-to-grain supercurrent transport, Dr. Goyal focused his energy in transitioning this fundamental understanding into cutting-edge technologies. Under OE sponsorship, Dr. Goyal co-invented the Rolling Assisted Bi-Axially Textured Substrate technology (RABiTS) that is used as a substrate for second generation HTS wires. OE support also led to the invention of Structural Single Crystal Faceted Fiber Substrate (SSIFFS) and the 3-D Self Assembly of Nanodot Columns. These inventions and associated R&D resulted in 7 R&D 100 Awards including the 2010 R&D Magazine's Innovator of the Year Award, 3 Federal Laboratory Consortium Excellence in Technology Transfer National Awards, a DOE Energy100 Award and many others. As a world authority on HTS materials, Dr. Goyal has presented OE-sponsored results in more than 150 invited talks, co-authored more than 350 papers and is a fellow of 7 professional societies.

Goyal, Amit (Oak Ridge National Laboratory)

2012-06-28T23:59:59.000Z

118

Regional Analysis And Characterization Of Fractured Aquifers In The  

Open Energy Info (EERE)

Analysis And Characterization Of Fractured Aquifers In The Analysis And Characterization Of Fractured Aquifers In The Virginia Blue Ridge And Piedmont Provinces Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Regional Analysis And Characterization Of Fractured Aquifers In The Virginia Blue Ridge And Piedmont Provinces Details Activities (1) Areas (1) Regions (0) Abstract: Areas related to low-temperature geothermal applications include the recognition of and exploration for deep fracture permeability in crystalline rocks. It is well known that the best currently available downhole techniques to identify the locations of fracture zones in crystalline rocks depend upon the measurement of some thermal parameter such as temperature or heat flow. The temperature-depth profiles and their derivatives provide a direct indication of those fracture zones that

119

Macroscopic Biofilms in Fracture-Dominated Sediment That Anaerobically Oxidize Methane  

Science Journals Connector (OSTI)

...resistivity values caused by high gas hydrate saturation in the fractures (41...fractures partially filled with gas hydrate and feeding methane upwards toward...collected as a part of the National Gas Hydrate Program cruise 01 (NGHP01) in...

B. R. Briggs; J. W. Pohlman; M. Torres; M. Riedel; E. L. Brodie; F. S. Colwell

2011-08-05T23:59:59.000Z

120

Development, setup and testing of a dynamic hydraulic fracture conductivity apparatus  

E-Print Network [OSTI]

One of the most critical parameters in the success of a hydraulic fracturing treatment is to have sufficiently high fracture conductivity. Unbroken polymers can cause permeability impairment in the proppant pack and/or in the matrix along...

Pongthunya, Potcharaporn

2009-06-02T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Scale-Dependent Fracture-Matrix Interactions and Their Impact on Radionuclide Transport: Development of efficient particle-tracking methods  

SciTech Connect (OSTI)

Matrix Diffusion and Adsorption within a rock matrix are important mechanisms for retarding transport of radionuclides in fractured rock. Due to computational limitations and difficulties in characterizing complex subsurface systems, diffusive exchange between a fracture network and surrounding rock matrix is often modeled using simplified conceptual representations. There is significant uncertainty in “effective” parameters used in these models, such as the “effective matrix diffusivity”. Often, these parameters are estimated by fitting sparse breakthrough data, and estimated values fall outside meaningful ranges, because simplified interpretive models do not consider complex three-dimensional flow. There is limited understanding of the relationship between the effective parameters and rock mass characteristics including network structure and matrix properties. There is also evidence for an apparent scale-dependence in “effective matrix diffusion” coefficients. These observations raise questions on whether fracture-matrix interaction parameters estimated from small-scale tracer tests can be used for predicting radionuclide fate and transport at the scale of DOE field sites. High-resolution three-dimensional Discrete-Fracture-Network-Matrix (DFNM) models based on well-defined local scale transport equations can help to address some of these questions. Due to tremendous advances in computational technology over the last 10 years, DFNM modeling in relatively large domains is now feasible. The overarching objective of our research is to use DFNM modeling to improve fundamental understanding of how effective parameters in conceptual models are related to fracture network structure and matrix properties. An advanced three-dimensional DFNM model is being developed, which combines upscaled particle-tracking algorithms for fracture-matrix interaction and a parallel fracture-network flow simulator. The particle-tracking algorithms allow complexity in flow fields at different scales, and track transport across fracture-matrix interfaces based on rigorous local approximations to the transport equations. This modeling approach can incorporate aperture variability, multi-scale preferential flow and matrix heterogeneity. We developed efficient particle-tracking methods for handling matrix diffusion and adsorption on fracture walls and demonstrated their efficiency for use within the context of large-scale complex fracture network models with variability in apertures across a network of fractures and within individual fractures.

Rajaram, Harihar [University of Colorado, Boulder; Brutz, Michael [University of Colorado, Boulder; Klein, Dylan R [University of Colorado, Boulder; Mallikamas, Wasin [University of Colorado, Boulder

2014-09-18T23:59:59.000Z

122

Production-systems analysis for fractured wells  

SciTech Connect (OSTI)

Production-systems analysis has been in use for many years to design completion configurations on the basis of an expected reservoir capacity. The most common equations used for the reservoir calculations are for steady-state radial flow. Most hydraulically fractured wells require the use of an unsteady-state production simulator to predict the higher flow rates associated with the stimulated well. These high flow rates may present problems with excessive pressure drops through production tubing designed for radial-flow production. Therefore, the unsteady-state nature of fractured-well production precludes the use of steady-state radial-flow inflow performance relationships (IPR's) to calculate reservoir performance. An accurate prediction of fractured-well production must be made to design the most economically efficient production configuration. It has been suggested in the literature that a normalized reference curve can be used to generate the IPR's necessary for production-systems analysis. However, this work shows that the reference curve for fractured-well response becomes time-dependent when reservoir boundaries are considered. A general approach for constructing IPR curves is presented, and the use of an unsteady-state fractured-well-production simulator coupled with the production-systems-analysis approach is described. A field case demonstrates the application of this method to fractured wells.

Hunt, J.L. (Halliburton Services (US))

1988-11-01T23:59:59.000Z

123

Naturally fractured tight gas reservoir detection optimization. Annual report, September 1993--September 1994  

SciTech Connect (OSTI)

This report is an annual summarization of an ongoing research in the field of modeling and detecting naturally fractured gas reservoirs. The current research is in the Piceance basin of Western Colorado. The aim is to use existing information to determine the most optimal zone or area of fracturing using a unique reaction-transport-mechanical (RTM) numerical basin model. The RTM model will then subsequently help map subsurface lateral and vertical fracture geometries. The base collection techniques include in-situ fracture data, remote sensing, aeromagnetics, 2-D seismic, and regional geologic interpretations. Once identified, high resolution airborne and spaceborne imagery will be used to verify the RTM model by comparing surficial fractures. If this imagery agrees with the model data, then a further investigation using a three-dimensional seismic survey component will be added. This report presents an overview of the Piceance Creek basin and then reviews work in the Parachute and Rulison fields and the results of the RTM models in these fields.

NONE

1994-10-01T23:59:59.000Z

124

Suspensions in hydraulic fracturing  

SciTech Connect (OSTI)

Suspensions or slurries are widely used in well stimulation and hydraulic fracturing processes to enhance the production of oil and gas from the underground hydrocarbon-bearing formation. The success of these processes depends significantly upon having a thorough understanding of the behavior of suspensions used. Therefore, the characterization of suspensions under realistic conditions, for their rheological and hydraulic properties, is very important. This chapter deals with the state-of-the-art hydraulic fracturing suspension technology. Specifically it deals with various types of suspensions used in well stimulation and fracturing processes, their rheological characterization and hydraulic properties, behavior of suspensions in horizontal wells, review of proppant settling velocity and proppant transport in the fracture, and presently available measurement techniques for suspensions and their merits. Future industry needs for better understanding of the complex behavior of suspensions are also addressed. 74 refs., 21 figs., 1 tab.

Shah, S.N. [Univ. of Oklahoma, Norman, OK (United States)

1996-12-31T23:59:59.000Z

125

Testing the fracture of spectacle lenses Stephen K. Lucas1  

E-Print Network [OSTI]

involves many physical processes, including im- pact phenomenon, the relationship of static test results centres in Adelaide and Petaluma, California; sup- ported by a specialist process engineering team impact strength, while lens coat- ing facilitates the fracture process, and tends to focus the fracture

Lucas, Stephen

126

Mapping Fractures In The Medicine Lake Geothermal System | Open Energy  

Open Energy Info (EERE)

Fractures In The Medicine Lake Geothermal System Fractures In The Medicine Lake Geothermal System Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Mapping Fractures In The Medicine Lake Geothermal System Details Activities (1) Areas (1) Regions (0) Abstract: A major challenge to energy production in the region has been locating high-permability fracture zones in the largely impermeable volcanic host rock. An understanding of the fracture networks will be a key to harnessing geothermal resources in the Cascades Author(s): Steven Clausen, Michal Nemcok, Joseph Moore, Jeffrey Hulen, John Bartley Published: GRC, 2006 Document Number: Unavailable DOI: Unavailable Core Analysis At Medicine Lake Area (Clausen Et Al, 2006) Medicine Lake Geothermal Area Retrieved from "http://en.openei.org/w/index.php?title=Mapping_Fractures_In_The_Medicine_Lake_Geothermal_System&oldid=388927

127

Hydraulic fracturing and geothermal energy development in Japan  

SciTech Connect (OSTI)

This paper is a review of research and development on geothermal energy extraction in Japan especially on hydraulic fracturing. First recent geothermal developments in Japan are outlined in Part I. An increase in the production rate of geothermal wells may be highly dependent on the geothermal well stimulation technology based on hydraulic fracturing. The hydraulic fracturing technique must be developed also for geothermal energy to be extracted from hot, dry rock masses. In Part II, the research on hydraulic fracturing and field application are reviewed.

Abe, H.; Suyama, J.; Takahashi, H.

1982-09-01T23:59:59.000Z

128

On the fracture toughness of advanced materials  

E-Print Network [OSTI]

occurs when the materials resistance to fracture ceases toall classes of materials, the fracture resistance does notthese biological materials derive their fracture resistance

Launey, Maximilien E.

2009-01-01T23:59:59.000Z

129

Hydraulic Fracturing Poster | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Hydraulic Fracturing Poster Hydraulic Fracturing Poster Educational poster graphically displaying the key components of hydraulic fracturing. Teachers: If you would like hard...

130

Self-potential observations during hydraulic fracturing  

E-Print Network [OSTI]

potential measurements during hydraulic fracturing of BunterSP response during hydraulic fracturing. Citation: Moore, J.observations during hydraulic fracturing, J. Geophys. Res. ,

Moore, J R; Glaser, Steven D

2007-01-01T23:59:59.000Z

131

Geothermal Ultrasonic Fracture Imager | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Geothermal Ultrasonic Fracture Imager Geothermal Ultrasonic Fracture Imager Development of a downhole wireline tool to characterize fractures in EGS wells in temperatures up to...

132

Ultrasound-Confirmed Frontal Bone Fracture  

E-Print Network [OSTI]

table--frontal sinus fractures. Facial Plast Surg Clin NorthConfirmed Frontal Bone Fracture Jeremy N. Johnson, DO Danielan isolated comminuted fracture of the left frontal sinus

Johnson, Jeremy N; Crandall, Stephen; Kang, Christopher S

2009-01-01T23:59:59.000Z

133

Fracture, aging and disease in bone  

E-Print Network [OSTI]

separate during bone fracture. Nature Materials 4, 612 (on nonagenarians with hip fractures? Injury 30, 169 (1999).bone mass as predictors of fracture in a prospective study.

Ager, J.W.; Balooch, G.; Ritchie, R.O.

2006-01-01T23:59:59.000Z

134

Field fracturing multi-sites project. Annual technical progress report, July 28, 1993--July 31, 1994  

SciTech Connect (OSTI)

The objective of the Field Fracturing Multi-Sites Project (M-Site) is to conduct experiments to definitively determine hydraulic fracture dimensions using remote well and treatment well diagnostic techniques. In addition, experiments will be conducted to provide data which will resolve significant unknowns with regard to hydraulic fracture modeling, fluid fracture rheology and fracture treatment design. These experiments will be supported by a well-characterized subsurface environment, as well as surface facilities and equipment that are conducive to acquiring high-quality data. The goal is to develop a fully characterized, tight reservoir-typical, field-scale hydraulic-fracturing test site.

Not Available

1995-02-01T23:59:59.000Z

135

Meals included in Conference Registrations  

E-Print Network [OSTI]

Meals included in Conference Registrations Meals included as part of the cost of a conference the most reasonable rates are obtained. Deluxe hotels and motels should be avoided. GSA rates have been for Georgia high cost areas. 75% of these amounts would be $21 for non- high cost areas and $27 for high cost

Arnold, Jonathan

136

Studying Hydraulic Fracturing through Time-variant Seismic Anisotropy  

E-Print Network [OSTI]

Hydraulic fracturing is an important modern technique of exploiting natural gas and oil, in which a high-pressure liquid mixture is injected into a wellbore to create small fractures in order to release fluids such as natural gas and petroleum...

Liu, Qifan

2013-10-01T23:59:59.000Z

137

LNG cascading damage study. Volume I, fracture testing report.  

SciTech Connect (OSTI)

As part of the liquefied natural gas (LNG) Cascading Damage Study, a series of structural tests were conducted to investigate the thermal induced fracture of steel plate structures. The thermal stresses were achieved by applying liquid nitrogen (LN{sub 2}) onto sections of each steel plate. In addition to inducing large thermal stresses, the lowering of the steel temperature simultaneously reduced the fracture toughness. Liquid nitrogen was used as a surrogate for LNG due to safety concerns and since the temperature of LN{sub 2} is similar (-190 C) to LNG (-161 C). The use of LN{sub 2} ensured that the tests could achieve cryogenic temperatures in the range an actual vessel would encounter during a LNG spill. There were four phases to this test series. Phase I was the initial exploratory stage, which was used to develop the testing process. In the Phase II series of tests, larger plates were used and tested until fracture. The plate sizes ranged from 4 ft square pieces to 6 ft square sections with thicknesses from 1/4 inches to 3/4 inches. This phase investigated the cooling rates on larger plates and the effect of different notch geometries (stress concentrations used to initiate brittle fracture). Phase II was divided into two sections, Phase II-A and Phase II-B. Phase II-A used standard A36 steel, while Phase II-B used marine grade steels. In Phase III, the test structures were significantly larger, in the range of 12 ft by 12 ft by 3 ft high. These structures were designed with more complex geometries to include features similar to those on LNG vessels. The final test phase, Phase IV, investigated differences in the heat transfer (cooling rates) between LNG and LN{sub 2}. All of the tests conducted in this study are used in subsequent parts of the LNG Cascading Damage Study, specifically the computational analyses.

Petti, Jason P.; Kalan, Robert J.

2011-12-01T23:59:59.000Z

138

Acid Fracture and Fracture Conductivity Study of Field Rock Samples  

E-Print Network [OSTI]

Acid fracturing is a well stimulation strategy designed to increase the productivity of a producing well. The parameters of acid fracturing and the effects of acid interaction on specific rock samples can be studied experimentally. Acid injection...

Underwood, Jarrod

2013-11-15T23:59:59.000Z

139

Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture  

E-Print Network [OSTI]

Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture Brian Somerday for producing both strength of materials and fracture mechanics data H H HH H H d/dt > 0 strength of materials: UTS, YS, f, RA H2 H2H2 H2 H2 H2 H2 H2 HH H H H H H H H H d/dt 0 fracture mechanics: KIH, KTH

140

Reservoir fracture characterizations from seismic scattered waves  

E-Print Network [OSTI]

The measurements of fracture parameters, such as fracture orientation, fracture density and fracture compliance, in a reservoir is very important for field development and exploration. Traditional seismic methods for ...

Fang, Xinding

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

New Tracers Identify Hydraulic Fracturing Fluids and Accidental Releases from Oil and Gas Operations  

E-Print Network [OSTI]

New Tracers Identify Hydraulic Fracturing Fluids and Accidental Releases from Oil and Gas fingerprints of fluids that return to the surface after high volume hydraulic fracturing of unconventional oil the hydraulic fracturing process, resulting in the relative enrichment of boron and lithium in HFFF

Jackson, Robert B.

142

Fracture morphology and viscous transport J. Schmittbuhl, A. Steyer, L. Jouniaux and R. Toussaint  

E-Print Network [OSTI]

Fracture morphology and viscous transport J. Schmittbuhl, A. Steyer, L. Jouniaux and R. Toussaint, France Abstract The morphology of a fracture in a granite block is sampled using a high resolution is an accurate geometrical model of the fracture morphology on the basis of a spectral analysis. We also

Toussaint, Renaud

143

Application of microseismic technology to hydraulic fracture diagnostics: GRI/DOE Field Fracturing Multi-Sites Project  

SciTech Connect (OSTI)

The objective of the Field Fracturing Multi-Sites Project (M-Site) is to conduct field experiments and analyze data that will result in definitive determinations of hydraulic fracture dimensions using remote well and treatment well diagnostic techniques. In addition, experiments will be conducted to provide data that will resolve significant unknowns with regard to hydraulic fracture modeling, fracture fluid rheology and fracture treatment design. These experiments will be supported by a well-characterized subsurface environment as well as surface facilities and equipment conducive to acquiring high-quality data. It is anticipated that the project`s research advancements will provide a foundation for a fracture diagnostic service industry and hydraulic fracture optimization based on measured fracture response. The M-Site Project is jointly sponsored by the Gas Research Institute (GRI) and the US Department of Energy (DOE). The site developed for M-Site hydraulic fracture experimentation is the former DOE Multiwell Experiment (MWX) site located near Rifle, Colorado. The MWX project drilled three closely-spaced wells (MWX-1, MWX-2 and MWX-3) which were the basis for extensive reservoir analyses and tight gas sand characterizations in the blanket and lenticular sandstone bodies of the Mesaverde Group. The research results and background knowledge gained from the MWX project are directly applicable to research in the current M-Site Project.

Wilmer, R. [CER Corp., Las Vegas, NV (United States); Warpinski, N.R. [Sandia National Laboratories (United States); Wright, T.B. [Resources Engineering Systems (United States); Branagan, P.T. [Branagan & Associates (United States); Fix, J.E. [Fix & Associates (United States)

1995-06-01T23:59:59.000Z

144

Seismic Fracture Characterization Methods for Enhanced Geothermal...  

Broader source: Energy.gov (indexed) [DOE]

Seismic Fracture Characterization Methods for Enhanced Geothermal Systems Seismic Fracture Characterization Methods for Enhanced Geothermal Systems Project objective: Make Seismic...

145

Seismic Fracture Characterization Methods for Enhanced Geothermal...  

Broader source: Energy.gov (indexed) [DOE]

Seismic Fracture Characterization Methods for Enhanced Geothermal Systems; 2010 Geothermal Technology Program Peer Review Report Seismic Fracture Characterization Methods for...

146

Microearthquake Technology for EGS Fracture Characterization...  

Broader source: Energy.gov (indexed) [DOE]

Microearthquake Technology for EGS Fracture Characterization; 2010 Geothermal Technology Program Peer Review Report Microearthquake Technology for EGS Fracture Characterization;...

147

Fluid Flow Modeling in Fractures  

E-Print Network [OSTI]

In this paper we study fluid flow in fractures using numerical simulation and address the challenging issue of hydraulic property characterization in fractures. The methodology is based on Computational Fluid Dynamics, ...

Sarkar, Sudipta

2004-01-01T23:59:59.000Z

148

HFIR vessel probabilistic fracture mechanics analysis  

SciTech Connect (OSTI)

The life of the High Flux Isotope Reactor (HFIR) pressure vessel is limited by a radiation induced reduction in the material`s fracture toughness. Hydrostatic proof testing and probabilistic fracture mechanics analyses are being used to meet the intent of the ASME Code, while extending the life of the vessel well beyond its original design value. The most recent probabilistic evaluation is more precise and accounts for the effects of gamma as well as neutron radiation embrittlement. This analysis confirms the earlier estimates of a permissible vessel lifetime of at least 50 EFPY (100 MW).

Cheverton, R.D. [Delta-21 Resources, Inc., Oak Ridge, TN (United States); Dickson, T.L. [Oak Ridge National Lab., TN (United States)

1997-01-01T23:59:59.000Z

149

FRACTURE STIMULATION IN ENHANCED GEOTHERMAL  

E-Print Network [OSTI]

FRACTURE STIMULATION IN ENHANCED GEOTHERMAL SYSTEMS A REPORT SUBMITTED TO THE DEPARTMENT OF ENERGY of stimulation is induced shear on preexisting fractures, which increases their transmissibility by orders of magnitude. The processes that create fractured rock are discussed from the perspective of geology and rock

Stanford University

150

Naturally fractured tight gas reservoir detection optimization. Quarterly report, July 1--September 30, 1994  

SciTech Connect (OSTI)

Research continued in the detection of naturally fractured tight gas reservoirs. Tasks include modeling, data analysis, geologic assessment of the Piceance Basin, and remote sensing.

NONE

1997-05-01T23:59:59.000Z

151

Fracture permeability and seismic wave scattering--Poroelastic linear-slip interface model for heterogeneous fractures  

E-Print Network [OSTI]

modeling of faults and fractures: Geophysics, 60, 1514-1526.Poroelastic modeling of fracture-seismic wave interaction:by a heterogeneous fracture: J. Acoust. Soc. Am. , 115,

Nakagawa, S.

2010-01-01T23:59:59.000Z

152

The Role of Acidizing in Proppant Fracturing in Carbonate Reservoirs  

E-Print Network [OSTI]

of the most widely considered alternatives for application in carbonate reservoirs. Especially in areas that have high closure stress, the non-smoothly etched surface created by acid fracturing may not remain open upon closing, resulting in decrease...

Densirimongkol, Jurairat

2010-10-12T23:59:59.000Z

153

Fracture Characterization in Enhanced Geothermal Systems by Wellbore...  

Broader source: Energy.gov (indexed) [DOE]

Nanosensors for Fractured Reservoir Characterization. 2. Characterization of Fracture Properties using Production Data. 3. Fracture Characterization by Resistivity...

154

Coupled Analysis of Change in Fracture Permeability during the Cooling Phase of the Yucca Mountain Drift Scale Test  

SciTech Connect (OSTI)

This paper presents results from a coupled thermal, hydrological and mechanical analysis of thermally-induced permeability changes during heating and cooling of fractured volcanic rock at the Drift Scale Test at Yucca Mountain, Nevada. The analysis extends the previous analysis of the four-year heating phase to include newly available data from the subsequent four year cooling phase. The new analysis of the cooling phase shows that the measured changes in fracture permeability follows that of a thermo-hydro-elastic model on average, but at several locations the measured permeability indicates (inelastic) irreversible behavior. At the end of the cooling phase, the air-permeability had decreased at some locations (to as low as 0.2 of initial), whereas it had increased at other locations (to as high as 1.8 of initial). Our analysis shows that such irreversible changes in fracture permeability are consistent with either inelastic fracture shear dilation (where permeability increased) or inelastic fracture surface asperity shortening (where permeability decreased). These data are important for bounding model predictions of potential thermally-induced changes in rock-mass permeability at a future repository at Yucca Mountain.

Rutqvist, Jonny; Rutqvist, J.; Freifeld, B.; Tsang, Y.W.; Min, K.B.; Elsworth, D.

2008-06-01T23:59:59.000Z

155

Use of Tracers to Characterize Fractures in Engineered Geothermal...  

Broader source: Energy.gov (indexed) [DOE]

Fractures in Engineered Geothermal Systems Project Objectives: Measure interwell fracture surface area and fracture spacing using sorbing tracers; measure fracture surface...

156

Introduction to the GRI/DOE Field Fracturing Multi-Site Project  

SciTech Connect (OSTI)

The objective of the Field Fracturing Multi-Sites Project is to conduct field experiments and analyze data that will result in definitive determinations of hydraulic fracture dimensions using remote well and treatment well diagnostic techniques. In addition, experiments will be conducted to provide data that will resolve significant unknowns with regard to hydraulic fracture modeling, fracture fluid rheology and fracture treatment design. These experiments will be supported by a well-characterized subsurface environment, as well as surface facilities and equipment that are conducive to acquiring high-quality data. It is anticipated that the primary benefit of the project experiments will be the development and widespread commercialization of new fracture diagnostics technologies to determine fracture length, height, width and azimuth. Data resulting from these new technologies can then be used to prove and refine the 3D fracture model mechanisms. It is also anticipated that data collected and analyzed in the project will define the correct techniques for determining fracture closure pressure. The overall impact of the research will be to provide a foundation for a fracture diagnostic service industry and hydraulic fracture optimization based on measured fracture response.

Peterson, R.E.; Middlebrook, M.L.; Warpinski, N.R.; Cleary, M.P.; Branagan, P.T.

1993-12-31T23:59:59.000Z

157

Procedure for estimating fracture energy from fracture surface roughness  

DOE Patents [OSTI]

The fracture energy of a material is determined by first measuring the length of a profile of a section through a fractured surface of the material taken on a plane perpendicular to the mean plane of that surface, then determining the fractal dimensionality of the surface. From this, the yield strength of the material, and the Young's Modulus of that material, the fracture energy is calculated.

Williford, Ralph E. (Kennewick, WA)

1989-01-01T23:59:59.000Z

158

Low Alloy Steel Susceptibility to Stress Corrosion Cracking in Hydraulic Fracturing Environment.  

E-Print Network [OSTI]

??The pipelines used for hydraulic fracturing (aka. "fracking") are often operating at a pressure above 10000psi and thus are highly susceptible to Stress Corrosion Cracking… (more)

Anyanwu, Ezechukwu John

2014-01-01T23:59:59.000Z

159

E-Print Network 3.0 - artificial rock fractures Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

3 Hydromechanical modelling of pulse tests that measure fluid pressure and fracture normal displacement at the Coaraze Laboratory site, France Summary: -vertical highly...

160

Enhanced oil recovery through water imbibition in fractured reservoirs using Nuclear Magnetic Resonance.  

E-Print Network [OSTI]

??Conventional waterflooding methods of oil recovery are difficult to apply when reservoirs show evidence of natural fractures, because injected water advances through paths of high… (more)

Hervas Ordonez, Rafael Alejandro

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Brittle Fracture Ductile to Brittle transition  

E-Print Network [OSTI]

FRACTURE Brittle Fracture Ductile to Brittle transition Fracture Mechanics T.L. Anderson CRC sulphur in steel Residual stress Continuity of the structure Microcracks #12;Fracture Brittle Ductile Factors affecting fracture Strain rate State of stress Temperature #12;Behaviour described Terms Used

Subramaniam, Anandh

162

In Situ Characterization of a Single Fracture Hydromechanical Behavior from Hydraulic Pulse Tests coupled to Simultaneous Pressure Normal  

E-Print Network [OSTI]

In Situ Characterization of a Single Fracture Hydromechanical Behavior from Hydraulic Pulse Tests of the other surrounding fractures of the network. 1 INTRODUCTION Hydraulic pulse injection testing in single borehole has previously been applied to determine hydraulic properties of rock fractures, including

Vallée, Martin

163

August 22, 2012 (v. 5) Summary of Studies Related to Hydraulic Fracturing Conducted by USGS Water Science Centers  

E-Print Network [OSTI]

August 22, 2012 (v. 5) Summary of Studies Related to Hydraulic Fracturing Conducted by USGS Water and hydraulic fracturing on groundwater and surface-water quantity and quality and ecosystems. "On ­ Maps related to oil and gas production and hydraulic fracturing are included in the USGS Fact Sheet

164

Simulation studies to evaluate the effect of fracture closure on the performance of naturally fractured reservoirs. Annual report  

SciTech Connect (OSTI)

The second year of this three-year research program to evaluate the effect of fracture closure on the recovery of oil and gas from naturally fractured reservoirs has been completed. The overall objectives of the study are to: (1) evaluate the reservoir conditions where fracture closure is significant, and (2) evaluate innovative fluid injection techniques capable of maintaining pressure within the reservoir. Simulation studies have been conducted with a dual porosity simulator capable of simulating the performance of vertical and horizontal wells. Each simulation model has been initialized with properties typical of the Austin Chalk reservoir in Pearsall Field, Texas. During year one, simulations of both vertical and horizontal well performance were made assuming that fracture permeability was insensitive to pressure charge. The results confirmed that horizontal wells could increase both rate of oil recovery and total oil recovery from naturally fractured reservoirs. During the second year the performances of the same vertical and horizontal wells were evaluated with the assumption that fracture permeability was a function of reservoir pressure. This required repetition of most of the natural depletion cases simulated in year one while invoking the pressure-sensitive fracture permeability option. To investigate sensitivity to in situ stress, two stress conditions were simulated for each primary variable. The water injection cases, begun in year one, were extended to include most of the reservoir parameters investigated for natural depletion, including fracture permeability as a function of net stress and the use of horizontal wells. The results thus far confirm that pressure-sensitive fractures degrade well performance and that the degradation is reduced by water injection pressure maintenance. Furthermore, oil recovery can be significantly increased by water injection pressure maintenance.

Not Available

1992-11-01T23:59:59.000Z

165

NETL Releases Hydraulic Fracturing Study  

Broader source: Energy.gov [DOE]

The National Energy Technology Laboratory has released a technical report on the results of a limited field study that monitored a hydraulic fracturing operation in Greene County, PA.

166

Fracture model for cemented aggregates  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

A mechanisms-based fracture model applicable to a broad class of cemented aggregates and, among them, plastic-bonded explosive (PBX) composites, is presented. The model is calibrated for PBX 9502 using the available experimental data under uniaxial compression and tension gathered at various strain rates and temperatures. We show that the model correctly captures inelastic stress-strain responses prior to the load peak and it predicts the post-critical macro-fracture processes, which result from the growth and coalescence of micro-cracks. In our approach, the fracture zone is embedded into elastic matrix and effectively weakens the material's strength along the plane of the dominant fracture.

Zubelewicz, Aleksander; Thompson, Darla G.; Ostoja-Starzewski, Martin; Ionita, Axinte; Shunk, Devin; Lewis, Matthew W.; Lawson, Joe C.; Kale, Sohan; Koric, Seid

2013-01-01T23:59:59.000Z

167

Complications in Ankle Fracture Surgery.  

E-Print Network [OSTI]

??Mikko Ovaska. Complications in Ankle Fracture Surgery. Helsinki Bone and Joint Research Group, Department of Orthopaedic Surgery and Traumatology, Faculty of Medicine, University of Helsinki,… (more)

Ovaska, Mikko

2014-01-01T23:59:59.000Z

168

Seismic anisotropy of fractured rock  

E-Print Network [OSTI]

A comparison of the theory with recent ultra- sonic experiments on a simulated fractured medium .... Note that Poisson's ratio and Young's modulus for the.

M. Schoenberg, C. M. Sayers

2000-02-18T23:59:59.000Z

169

Fractured reservoir discrete feature network technologies. Annual report, March 7, 1996--February 28, 1997  

SciTech Connect (OSTI)

This report describes progress on the project, {open_quotes}Fractured Reservoir Discrete Feature Network Technologies{close_quotes} during the period March 7, 1996 to February 28, 1997. The report presents summaries of technology development for the following research areas: (1) development of hierarchical fracture models, (2) fractured reservoir compartmentalization and tributary volume, (3) fractured reservoir data analysis, and (4) integration of fractured reservoir data and production technologies. In addition, the report provides information on project status, publications submitted, data collection activities, and technology transfer through the world wide web (WWW). Research on hierarchical fracture models included geological, mathematical, and computer code development. The project built a foundation of quantitative, geological and geometrical information about the regional geology of the Permian Basin, including detailed information on the lithology, stratigraphy, and fracturing of Permian rocks in the project study area (Tracts 17 and 49 in the Yates field). Based on the accumulated knowledge of regional and local geology, project team members started the interpretation of fracture genesis mechanisms and the conceptual modeling of the fracture system in the study area. Research on fractured reservoir compartmentalization included basic research, technology development, and application of compartmentalized reservoir analyses for the project study site. Procedures were developed to analyze compartmentalization, tributary drainage volume, and reservoir matrix block size. These algorithms were implemented as a Windows 95 compartmentalization code, FraCluster.

Dershowitz, W.S.; La Pointe, P.R.; Einstein, H.H.; Ivanova, V.

1998-01-01T23:59:59.000Z

170

Investigation of the effect of gel residue on hydraulic fracture conductivity using dynamic fracture conductivity test  

E-Print Network [OSTI]

The key to producing gas from tight gas reservoirs is to create a long, highly conductive flow path, via the placement of a hydraulic fracture, to stimulate flow from the reservoir to the wellbore. Viscous fluid is used to transport proppant...

Marpaung, Fivman

2009-05-15T23:59:59.000Z

171

Pump apparatus including deconsolidator  

DOE Patents [OSTI]

A pump apparatus includes a particulate pump that defines a passage that extends from an inlet to an outlet. A duct is in flow communication with the outlet. The duct includes a deconsolidator configured to fragment particle agglomerates received from the passage.

Sonwane, Chandrashekhar; Saunders, Timothy; Fitzsimmons, Mark Andrew

2014-10-07T23:59:59.000Z

172

DISCOVERY OF FOUR HIGH PROPER MOTION L DWARFS, INCLUDING A 10 pc L DWARF AT THE L/T TRANSITION {sup ,}  

SciTech Connect (OSTI)

We discover four high proper motion L dwarfs by comparing the Wide-field Infrared Survey Explorer (WISE) to the Two Micron All Sky Survey. WISE J140533.32+835030.5 is an L dwarf at the L/T transition with a proper motion of 0.85 ± 0.''02 yr{sup –1}, previously overlooked due to its proximity to a bright star (V ? 12 mag). From optical spectroscopy we find a spectral type of L8, and from moderate-resolution J band spectroscopy we find a near-infrared spectral type of L9. We find WISE J140533.32+835030.5 to have a distance of 9.7 ± 1.7 pc, bringing the number of L dwarfs at the L/T transition within 10 pc from six to seven. WISE J040137.21+284951.7, WISE J040418.01+412735.6, and WISE J062442.37+662625.6 are all early L dwarfs within 25 pc, and were classified using optical and low-resolution near-infrared spectra. WISE J040418.01+412735.6 is an L2 pec (red) dwarf, a member of the class of unusually red L dwarfs. We use follow-up optical and low-resolution near-infrared spectroscopy to classify a previously discovered fifth object WISEP J060738.65+242953.4 as an (L8 Opt/L9 NIR), confirming it as an L dwarf at the L/T transition within 10 pc. WISEP J060738.65+242953.4 shows tentative CH{sub 4} in the H band, possibly the result of unresolved binarity with an early T dwarf, a scenario not supported by binary spectral template fitting. If WISEP J060738.65+242953.4 is a single object, it represents the earliest onset of CH{sub 4} in the H band of an L/T transition dwarf in the SpeX Library. As very late L dwarfs within 10 pc, WISE J140533.32+835030.5 and WISEP J060738.65+242953.4 will play a vital role in resolving outstanding issues at the L/T transition.

Castro, Philip J.; Gizis, John E. [Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Harris, Hugh C. [US Naval Observatory, Flagstaff Station, 10391 West Naval Observatory Road, Flagstaff, AZ 86001 (United States); Mace, Gregory N.; McLean, Ian S. [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095-1547 (United States); Kirkpatrick, J. Davy [Infrared Processing and Analysis Center, MS 100-22, California Institute of Technology, Pasadena, CA 91125 (United States); Pattarakijwanich, Petchara [Department of Astrophysical Sciences, Princeton University, Ivy Lane, Princeton, NJ 08544 (United States); Skrutskie, Michael F., E-mail: pcastro@udel.edu, E-mail: gizis@udel.edu [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)

2013-10-20T23:59:59.000Z

173

Hydraulic fracturing and associated stress modeling for the Eastern Gas Shales Project. Final report  

SciTech Connect (OSTI)

Frac fluid flow, structure, and fracture mechanics simulations are developed for predicting and optimizing fracture dimensions and fluid leak-offs. Roles of in situ stress and material properties for possible vertical migration of fractures from the pay zone are discussed. Rationale for foam and dendritic fracturing experiments is presented along with numerical experiments for examining the phenomena of spalling of the fracture faces and conditions for secondary fracture initiation. Assignment of conventional, foam, cyrogenic, dendritic, and explosive fracturing treatments for specific reservoir properties is considered. Variables include fracture density and extent, shale thickness, in-situ stress gradients, energy assist mechanisms, well clean-up, shale-frac fluid interaction, proppant selection, and fracture height control. The analysis suggests that correlation with prevailing in situ stress gradients are promising diagnostic indicators for fracture treatment selection and design. In conclusion, the comprehensive development of an economical strategy requires extensive and controlled field testing with supporting predictive analyses of reservoir responses. Finite element modeling of reservoir in situ stress trajectories and the flow and fracture responses in the reservoir is recommended.

Advani, S.H.

1980-12-01T23:59:59.000Z

174

Fracture compliance estimation using borehole tube waves  

E-Print Network [OSTI]

We tested two models, one for tube-wave generation and the other for tube-wave attenuation at a fracture intersecting a borehole that can be used to estimate fracture compliance, fracture aperture, and lateral extent. In ...

Bakku, Sudhish Kumar

175

GEOLOGY AND FRACTURE SYSTEM AT STRIPA  

E-Print Network [OSTI]

1978. An Approach to the Fracture Hydrology at Stripa:Shanley. 1972. Analysis of Fracture Orientations for InputHydraulic Pro erties of Fractures by P. A. Witherspoon, C.

Olkiewicz, O.

2010-01-01T23:59:59.000Z

176

Fracture and tensile properties of irradiated zircaloy-2 pressure tubes  

SciTech Connect (OSTI)

The mechanical properties of nuclear reactor components degrade as a result of long service exposure in high-temperature, irradiation, and corrosive environments. Fracture toughness and tensile testing are conducted on the pressure tubes of Zircaloy-2 to evaluate the effects of neutron fluence, hydrogen content, and temperature on the mechanical properties. Tensile tests are performed on the base metal, and fracture toughness tests are performed on both the base and weld metals. Neutron irradiation increases the strength, reduces ductility, and significantly degrades fracture toughness. The postirradiation fracture toughness increases substantially as the test temperature is increased from room temperature to 250 C. Hydrogen levels up to 250 ppm are found to have little or no effect on the postirradiation fracture toughness. Because of its anisotropic nature, Zircaloy-2 displays different fracture resistances, depending on crack orientation. In the base metal, the fracture toughness in the longitudinal orientation is higher than that for the circumferential orientation, and this difference is enhanced at higher temperatures. The weld exhibits lower toughness in the longitudinal direction.

Huang, F.H.; Mills, W.J. (Westinghouse Hanford Co., Richland, WA (United States))

1993-06-01T23:59:59.000Z

177

Experimental verification of dimensional analysis for hydraulic fracturing  

SciTech Connect (OSTI)

The authors have derived model laws that relate experimental parameters of a physical model of hydraulic fracture propagation to the prototype parameters. Correct representation of elastic deformation, fluid friction, crack propagation, and fluid leakoff forms the basis of the scaling laws. For tests at in-situ stress, high fluid viscosity and low fracture toughness are required. Tests on cement blocks agreed with the scale laws based on elastic behavior.

Pater, C.J. de; Weijers, L. (Delft Univ. of Technology (Netherlands)); Cleary, M.P.; Quinn, T.S. (Massachusetts Inst. of Tech., Cambridge, MA (United States)); Barr, D.T.; Johnson, D.E. (Resources Engineering Systems, Inc., Cambridge, MA (United States))

1994-11-01T23:59:59.000Z

178

Analysis of Best Hydraulic Fracturing Practices in the Golden Trend Fields of Oklahoma Shahab D. Mohaghegh, West Virginia University  

E-Print Network [OSTI]

Analysis of Best Hydraulic Fracturing Practices in the Golden Trend Fields of Oklahoma Shahab D of optimized hydraulic fracturing procedure. Detail stimulation data from more than 230 wells in the Golden of hydraulic fractures. Therefore, it is highly recommended that the clastic and carbonate formations

Mohaghegh, Shahab

179

A Critical Review of the Risks to Water Resources from Unconventional Shale Gas Development and Hydraulic Fracturing in  

E-Print Network [OSTI]

and Hydraulic Fracturing in the United States Avner Vengosh,*, Robert B. Jackson,, Nathaniel Warner,§ Thomas H: The rapid rise of shale gas development through horizontal drilling and high volume hydraulic fracturing has hydraulic fracturing. This paper provides a critical review of the potential risks that shale gas operations

Jackson, Robert B.

180

Evaluation of subsurface fracture geometry using fluid pressure response to  

Open Energy Info (EERE)

subsurface fracture geometry using fluid pressure response to subsurface fracture geometry using fluid pressure response to solid earth tidal strain Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Evaluation of subsurface fracture geometry using fluid pressure response to solid earth tidal strain Details Activities (1) Areas (1) Regions (0) Abstract: The nature of solid earth tidal strain and surface load deformation due to the influence of gravitational forces and barometric pressure loading are discussed. The pore pressure response to these types of deformation is investigated in detail, including the cases of a confined aquifer intersected by a well and a discrete fracture intersected by a well. The integration of the tidal response method with conventional pump tests in order to independently calculate the hydraulic parameters of the

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Microearthquake Technology for EGS Fracture Characterization  

Broader source: Energy.gov [DOE]

Project objectives: To understand how EGS fracture networks develop; To develop technology to determine accurate absolute three-dimensional positions of EGS fracture networks.

182

Seismic Fracture Characterization Methods for Enhanced Geothermal...  

Broader source: Energy.gov (indexed) [DOE]

Seismic Fracture Characterization Methods for Enhanced Geothermal Systems Principal Investigator: John H. Queen Hi-Q Geophysical Inc. Track Name: Seismicity and Reservoir Fracture...

183

Extension of the semi-empirical correlation for the effects of pipe diameter and internal surface roughness on the decompression wave speed to include High Heating Value Processed Gas mixtures  

Science Journals Connector (OSTI)

Abstract The decompression wave speed, which is used throughout the pipeline industry in connection with the Battelle two-curve method for the control of propagating ductile fracture, is typically calculated using GASDECOM (GAS DECOMpression). GASDECOM, developed in the 1970's, idealizes the decompression process as isentropic and one-dimensional, taking no account of pipe wall frictional effects or pipe diameter. Previous shock tube tests showed that decompression wave speeds in smaller diameter and rough pipes are consistently slower than those predicted by GASDECOM for the same conditions of mixture composition and initial pressure and temperature. Previous analysis based on perturbation theory and the fundamental momentum equation revealed a correction term to be subtracted from the ‘idealized’ value of the decompression speed calculated by GASDECOM. One parameter in this correction term involves a dynamic spatial pressure gradient of the outflow at the rupture location. While this is difficult to obtain without a shock tube or actual rupture test, data from 14 shock tube tests, as well as from 14 full scale burst tests involving a variety of gas mixture compositions, were analyzed to correlate the variation of this pressure gradient with two characteristics of the gas mixture, namely; the molecular weight and the higher heating value (HHV). For lean to moderately-rich gas mixes, the developed semi-empirical correlation was found to fit very well the experimentally determined decompression wave speed curve. For extremely rich gas mixes, such as High Heating Value Processed Gas (HHVPG) mixtures of HHV up to 58 MJ/m3, it was found that it overestimates the correction term. Therefore, additional shock tube tests were conducted on (HHVPG) mixes, and the previously developed semi-empirical correlation was extended (revised) to account for such extremity in the richness of the gas mixtures. The newly developed semi-empirical correlation covers a wider range of natural gas mixtures from as lean as pure methane up to HHVPG mixtures of HHV = 58 MJ/m3.

K.K. Botros; L. Carlson; M. Reed

2013-01-01T23:59:59.000Z

184

Orientation of hydraulic fractures in SALT under hydrostatic and non-hydrostatic stresses  

SciTech Connect (OSTI)

A series of laboratory experiments were performed to determine the influence of deviatoric in situ stress on the form and orientation of hydraulic fractures in salt. The principal hydraulic fracturing tests were run on prismatic blocks confined in a polyaxial loading frame using flatjacks. The vertical stress and the minimum horizontal stress were 10.3 MPa for all tests. The maximum horizontal stress was varied form 10.3 MPa to 15.5 MPa to provide a range of horizontal stress ratios from 1.0 (hydrostatic) to 1.5. The fracturing oil contained a fluorescent dye that marked the fracture traces for mapping after the samples were split. At high stress ratios (1.5) the hydraulic fractures formed as two distinct traces emanating from opposite sides of the borehole in the maximum horizontal stress direction. At progressively lower stress ratios the orientations of the fractures varied about the maximum stress direction, and the fracture traces tended to branch. At stress ratios below between 1.10 and 1.13 the fracture no longer appeared to have an orientation controlled by the in situ stress directions. The results indicate that the form of the hydraulic fracture reflects whether or not the stresses are nearly hydrostatic. Fracture form can be determined by mapping dyed hydraulic fractures underground. The fractures should be made in portions of an underground facility that are to be excavated, and the fractures should be mapped as the excavation proceeds through the area of fracturing. 2 refs., 13 figs., 2 tabs.

Doe, T.W.; Boyce, G.M.; Andrews, R.

1987-06-01T23:59:59.000Z

185

Failure of a gas well to respond to a foam hydraulic fracturing treatment  

SciTech Connect (OSTI)

Well No. 1 (not the real name of the well) is not producing gas at maximum capacity following a foam hydraulic fracturing treatment performed upon completion of the well in 1987. The failure of the stimulation treatment, which has affected other wells throughout the field, was due to a combination of three factors: (1) downward fracture growth and proppant settling during injection (2) embedment due to a high pressure drawdown in the wellbore during flowback procedures, and (3) poor cleanup of the fracture fluid due to high capillary pressures. The following are recommendations to help improve future fracturing treatments throughout the field: (1) Fracture at lower treating pressures; (2) Improve perforating techniques; (3) Change flowback procedures; and (4) Evaluate using N{sub 2} as a fracture fluid.

Rauscher, B.D.

1996-12-31T23:59:59.000Z

186

Fracturing Fluid Characterization Facility  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Documentation Page Documentation Page 1. Report No. DE - FC 21 - 92MC29077 2. 3. Recipient's Accession No. 5. Report Date August 31, 2000 4. Title and Subtitle Fracturing Fluid Characterization Facility 6. 7. Author(s) The University of Oklahoma 8. Performing Organization Rept. No. 10. Project/Task/Work Unit No. 9. Performing Organization Name and Address The University of Oklahoma Sarkeys Energy Center T301 100 E Boyd St Norman, OK 73019 11. Contract (C) or Grant (G) No. DOE:DE FC21 92 MC29077 13. Type of Report & Period Covered Final Report 09 30 92 - 03 31 00 12. Sponsoring Organization Name and Address US Dept of Energy - FETL 3610 Collins Ferry Road Morgantown, WV 26505 14. 15. Supplementary Notes Several technical papers were prepared and presented at various Society of Petroleum Engineers Conferences and US

187

Seismic signatures of the Lodgepole fractured reservoir in Utah-Wyoming overthrust belt  

SciTech Connect (OSTI)

In low porosity, low permeability zones, natural fractures are the primary source of permeability which affect both production and injection of fluids. The open fractures do not contribute much to porosity, but they provide an increased drainage network to any porosity. An important approach to characterizing the fracture orientation and fracture permeability of reservoir formations is one based upon the effects of such conditions on the propagation of acoustic and seismic waves in the rock. We present the feasibility of using seismic measurement techniques to map the fracture zones between wells spaced 2400 ft at depths of about 1000 ft. For this purpose we constructed computer models (which include azimuthal anisotropy) using Lodgepole reservoir parameters to predict seismic signatures recorded at the borehole scale, crosswell scale, and 3 D seismic scale. We have integrated well logs with existing 2D surfaces seismic to produce petrophysical and geological cross sections to determine the reservoir parameters and geometry for the computer models. In particular, the model responses are used to evaluate if surface seismic and crosswell seismic measurements can capture the anisotropy due to vertical fractures. Preliminary results suggested that seismic waves transmitted between two wells will propagate in carbonate fracture reservoirs, and the signal can be received above the noise level at the distance of 2400 ft. In addition, the large velocities contrast between the main fracture zone and the underlying unfractured Boundary Ridge Member, suggested that borehole reflection imaging may be appropriate to map and fracture zone thickness variation and fracture distributions in the reservoir.

Parra, J.; Collier, H.; Angstman, B.

1997-08-01T23:59:59.000Z

188

Finding Large Aperture Fractures in Geothermal Resource Areas Using a  

Open Energy Info (EERE)

Finding Large Aperture Fractures in Geothermal Resource Areas Using a Finding Large Aperture Fractures in Geothermal Resource Areas Using a Three-Component Long-Offset Surface Seismic Survey Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Finding Large Aperture Fractures in Geothermal Resource Areas Using a Three-Component Long-Offset Surface Seismic Survey Project Type / Topic 1 Recovery Act: Geothermal Technologies Program Project Type / Topic 2 Validation of Innovative Exploration Technologies Project Description Because fractures and faults with sub-commercial permeability can propagate hot fluid and hydrothermal alteration throughout a geothermal reservoir, potential field geophysical methods including resistivity, gravity, heatflow and magnetics cannot distinguish between low-permeability fractures and LAF's (Large Aperature Fractures). USG will develop and test the combination of three-component,long-offset seismic surveying, permanent scatter synthetic aperture radar interferometry (PSInSAR) and structural kinematic analysis as an integrated method for locating and 3-D mapping of LAF's in shallow to intermediate depth (600-4000 feet) geothermal systems. This project is designed to test the methodology on known occurrences of LAF's and then apply the technology to expand an existing production field and find a new production field in a separate but related resource area. A full diameter production well will be drilled into each of the two lease blocks covered by the geophysical exploration program.

189

SPALL FRACTURE AND SPALL FRACTURE AND COMPACTION COMPACTION  

National Nuclear Security Administration (NNSA)

SPALL FRACTURE AND SPALL FRACTURE AND SPALL FRACTURE AND SPALL FRACTURE AND COMPACTION COMPACTION IN NATURAL URANIUM IN NATURAL URANIUM UNDER SHOCK UNDER SHOCK - - WAVE LOADING WAVE LOADING O.A. O.A. Tyupanova Tyupanova , S.S. , S.S. Nadezhin Nadezhin , A.N. , A.N. Malyshev Malyshev , , O.N. O.N. Ignatova Ignatova , V.I. , V.I. Skokov Skokov , V.N. , V.N. Knyazev Knyazev , , V.A. V.A. Raevsky Raevsky , N.A. , N.A. Yukina Yukina Russian Federal Nuclear Center Russian Federal Nuclear Center - - VNIIEF, VNIIEF, Sarov Sarov , Russia , Russia Introduction Introduction  Nucleation and growth of defects inside a solid under pulse tensile stresses signify a necessity to consider it as a damaged medium.  A certain volume of experimental data, obtained in correct tests, which are sensitive to a characteristic under study, is necessary

190

Statistical Properties of Fracture Precursors  

Science Journals Connector (OSTI)

We present the data of a mode-I fracture experiment. The samples are broken under imposed pressure. The acoustic emission of microfractures before the breakup of the sample is registered. From the acoustic signals, the position of microfractures and the energy released are calculated. A measure of the clustering of microfractures yields information about the critical load. The statistics from energy measurements strongly suggest that the fracture can be viewed as a critical phenomenon; energy events are distributed in magnitude as a power law, and a critical exponent is found for the energy near fracture.

A. Garcimartín; A. Guarino; L. Bellon; S. Ciliberto

1997-10-27T23:59:59.000Z

191

Fracture of synthetic diamond M. D. Droty  

E-Print Network [OSTI]

Fracture of synthetic diamond M. D. Droty Ctystallume, 3506 Bassett Street, Santa Clara, California 1995) The fracture behavior of synthetic diamond has been investigated using indentation methods and by the tensile testing of pre-notched fracture-mechanics type samples. Specifically, the fracture toughness

Ritchie, Robert

192

Microstructure-Properties: IMicrostructure-Properties: I Lecture 6A: FractureLecture 6A: Fracture  

E-Print Network [OSTI]

-Properties: IMicrostructure-Properties: I Lecture 6A: FractureLecture 6A: Fracture 27-301 Fall, 2007 Prof. A. D. Rollett the fracture resistance of materials to their microstructure. · Both ceramics and metals exhibit strongly microstructure dependent fracture resistance. · This section focuses on basic theory of brittle fracture

Rollett, Anthony D.

193

Critical Fracture Stress and Fracture Strain Models for the Prediction of Lower and  

E-Print Network [OSTI]

Critical Fracture Stress and Fracture Strain Models for the Prediction of Lower and Upper Shelf fracture stress and stress modified fracture strain models are utilized to describe the variation of lower and upper shelf fracture toughness with temperature and strain rate for two alloy steels used

Ritchie, Robert

194

Journal of Biomechanics 38 (2005) 15171525 Fracture in human cortical bone: local fracture criteria and  

E-Print Network [OSTI]

Journal of Biomechanics 38 (2005) 1517­1525 Fracture in human cortical bone: local fracture, Livermore, CA 94550 Accepted 19 July 2004 Abstract Micromechanical models for fracture initiation such micromechanical models have been developed for the fracture of bone. In fact, although the fracture event

Ritchie, Robert O.

195

Hydraulic interactions between fractures and bedding planes in a carbonate aquifer studied by means of experimentally induced water-table fluctuations (Coaraze  

E-Print Network [OSTI]

1 Hydraulic interactions between fractures and bedding planes in a carbonate aquifer studied. Keywords: Karst, hydrogeochemistry, fractured rocks, hydraulic properties, France insu-00376151,version1 high and low permeability regions are controlled by the hydraulic head gradient. Past studies have

Boyer, Edmond

196

Characterizing Fractures in Geysers Geothermal Field by Micro-seismic Data,  

Open Energy Info (EERE)

Characterizing Fractures in Geysers Geothermal Field by Micro-seismic Data, Characterizing Fractures in Geysers Geothermal Field by Micro-seismic Data, Using Soft Computing, Fractals, and Shear Wave Anisotropy Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Characterizing Fractures in Geysers Geothermal Field by Micro-seismic Data, Using Soft Computing, Fractals, and Shear Wave Anisotropy Project Type / Topic 1 Recovery Act: Enhanced Geothermal Systems Component Research and Development/Analysis Project Type / Topic 2 Fracture Characterization Technologies Project Description The proposed program will focus on predicting characteristics of fractures and their orientation prior to drilling new wells. It will also focus on determining the location of the fractures, spacing and orientation during drilling, as well as characterizing open fractures after stimulation to help identify the location of fluid flow pathway within the EGS reservoir. These systems are created by passively injecting cold water, and stimulating the permeation of the injected water through existing fractures into hot wet and hot dry rocks by thermo-elastic cooling shrinkage. The stimulated, existing fractures thus enhance the permeability of the hot rock formations, hence enabling better circulation of water for the purpose of producing the geothermal resource. The main focus of the project will be on developing better understanding of the mechanisms for the stimulation of existing fractures, and to use the information for better exploitation of the high temperature geothermal resources located in the northwest portion of the Geysers field and similar fields.

197

State-of-the-art fracturing in the North Sea  

SciTech Connect (OSTI)

This paper will focus on recent advances in hydraulic fracturing technology with emphasis on North Sea applications. Five generalized applications that will benefit most from advances in technology have been identified. Because North Sea oil and gas field development requires the use of platform facilities for wellhead and processing equipment, deviated and horizontal wells are often used to effectively drain the reservoirs. Many of these wells require fracture stimulation. The success rate of such wells has increased significantly in recent years as a result of the following: Researchers better understand how fractures initiate and grow; Pre-treatment diagnostic techniques have improved substantially; Engineers better understand how completion design affects well performance. With improved understanding of post-frac well performance, engineers can evaluate the feasibility of developing a reservoir through fractured, horizontal wells. In addition to a review of the advances in HPHT technology that would apply to North Sea applications, this paper will identify improvements necessary before these techniques are applied in the North Sea. Hydraulic fracturing is being used more frequently (1) in high-permeability reservoirs to improve the overall profitability of the project, and (2) as an alternative to traditional sand control applications in soft, weakly consolidated reservoirs. The effect of hydraulic fracturing operations on the North Sea environment must be recognized. The advances in fluid design and post-treatment flowback procedures that minimize these effects are discussed. 78 refs., 19 figs.

Domelen, M.S. Van; Jacquier, R.C.; Sanders, M.W.

1995-12-31T23:59:59.000Z

198

Temporary Sealing of Fractures | Open Energy Information  

Open Energy Info (EERE)

Temporary Sealing of Fractures Temporary Sealing of Fractures Jump to: navigation, search Contents 1 Geothermal Lab Call Projects for Temporary Sealing of Fractures 2 Geothermal ARRA Funded Projects for Temporary Sealing of Fractures Geothermal Lab Call Projects for Temporary Sealing of Fractures Loading map... {"format":"googlemaps3","type":"ROADMAP","types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"limit":200,"offset":0,"link":"all","sort":[""],"order":[],"headers":"show","mainlabel":"","intro":"","outro":"","searchlabel":"\u2026

199

Sensitivity analysis of fracture scattering  

E-Print Network [OSTI]

We use a 2-D finite difference method to numerically calculate the seismic response of a single finite fracture in a homogeneous media. In our experiments, we use a point explosive source and ignore the free surface effect, ...

Fang, Xinding, S.M. Massachusetts Institute of Technology

2010-01-01T23:59:59.000Z

200

Environmental Impacts of Hydraulic Fracturing  

Science Journals Connector (OSTI)

...their environmental impacts, which has been published...the hydrogeological impacts of oil and gas development...Chafin, 1994), not fracking. Watson and Bachu...Frontiers Ecology Environment. 2011. 9( 9): 503...R. Environmental Impacts of Hydraulic Fracturing...

Richard Jackson

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Numerical simulation of hydraulic fracturing  

E-Print Network [OSTI]

NUMERICAL SIMULATION OF HYDRAULIC FRACTURING A Thesis by JOSEPH BARNES WARNER Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1987 Maj or Subj ect...: Petroleum Engineering NUMERICAL SIMULATION OF HYDRAULIC FRACTURING A Thesis by JOSEPH BARNES WARNER Approved as to style and content by: S. A. Holditch (Chairman of Committee) D. D. Van Fleet (member) J. E. Russell (m be ) W. D. Von onten ( ead...

Warner, Joseph Barnes

2012-06-07T23:59:59.000Z

202

Hyperbolic distributions and fractal character of fracture surfaces  

Science Journals Connector (OSTI)

The fractal character of fracture surfaces of thick-walled pressure vessels produced in the final fast fracture that terminates low-cycle-fatigue tests is compared with that of fracture surfaces produced in Charpy impact tests in samples of the same high-strength and -toughness steel (ASTM A723) alloy. Slit island analysis yielded fractal dimensions near 1.25 for the Charpy specimens, which is typical of high-strength steel alloys previously studied; however, extremely high fractal dimensions near 1.40 were determined for the low-cycle-fatigue specimens. The distributions of island and lake areas and of island and lake perimeters on random sections exhibit hyperbolic distributions analogous to those found for geographic islands and lakes.

Peter McAnulty; L. V. Meisel; P. J. Cote

1992-09-15T23:59:59.000Z

203

IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF THE COSO  

Open Energy Info (EERE)

IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF THE COSO IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF THE COSO GEOTHERMAL FIELD Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF THE COSO GEOTHERMAL FIELD Details Activities (1) Areas (1) Regions (0) Abstract: High rock temperatures, a high degree of fracturing, high tectonic stresses, and low permeability are the combination of qualities that define an ideal candidate-Enhanced Geothermal System (EGS) reservoir. The Coso Geothermal Field is an area where fluid temperatures exceeding 300°C have been measured at depths less than 10,000 feet and the reservoir is both highly fractured and tectonically stressed. Some of the wells within this portion of the reservoir are relatively impermeable,

204

Interpreting Fracture Patterns in Sandstones Interbedded with Ductile Strata at the Salt Valley Anticline, Arches National Park, Utah  

SciTech Connect (OSTI)

Sandstones that overlie or that are interbedded with evaporitic or other ductile strata commonly contain numerous localized domains of fractures, each covering an area of a few square miles. Fractures within the Entrada Sandstone at the Salt Valley Anticline are associated with salt mobility within the underlying Paradox Formation. The fracture relationships observed at Salt Valley (along with examples from Paleozoic strata at the southern edge of the Holbrook basin in northeastern Arizona, and sandstones of the Frontier Formation along the western edge of the Green River basin in southwestern Wyoming), show that although each fracture domain may contain consistently oriented fractures, the orientations and patterns of the fractures vary considerably from domain to domain. Most of the fracture patterns in the brittle sandstones are related to local stresses created by subtle, irregular flexures resulting from mobility of the associated, interbedded ductile strata (halite or shale). Sequential episodes of evaporite dissolution and/or mobility in different directions can result in multiple, superimposed fracture sets in the associated sandstones. Multiple sets of superimposed fractures create reservoir-quality fracture interconnectivity within restricted localities of a formation. However, it is difficult to predict the orientations and characteristics of this type of fracturing in the subsurface. This is primarily because the orientations and characteristics of these fractures typically have little relationship to the regional tectonic stresses that might be used to predict fracture characteristics prior to drilling. Nevertheless, the high probability of numerous, intersecting fractures in such settings attests to the importance of determining fracture orientations in these types of fractured reservoirs.

LORENZ, JOHN C.; COOPER, SCOTT P.

2001-12-01T23:59:59.000Z

205

A Comprehensive Study Of Fracture Patterns And Densities In The Geysers  

Open Energy Info (EERE)

Study Of Fracture Patterns And Densities In The Geysers Study Of Fracture Patterns And Densities In The Geysers Geothermal Reservoir Using Microearthquake Shear-Wave Splitting Tomography Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: A Comprehensive Study Of Fracture Patterns And Densities In The Geysers Geothermal Reservoir Using Microearthquake Shear-Wave Splitting Tomography Details Activities (1) Areas (1) Regions (0) Abstract: In this project we developed a method for using seismic S-wave data to map the patterns and densities of sub-surface fractures in the NW Geysers Geothermal Field/ (1) This project adds to both the general methods needed to characterize the geothermal production fractures that supply steam for power generation and to the specific knowledge of these in the Geysers area. (2)By locating zones of high fracture density it will be

206

Comparison of Discrete Fracture and Effective Media Representation of Fractures on Azimuthal AVO  

E-Print Network [OSTI]

In fractured reservoir development, azimuthal AVO (AVOaz) properties of reflected PP waves from reservoir tops are often used to infer fracture properties. The fracture parameter inversion is based on either an effective ...

Zhang, Yang

2005-01-01T23:59:59.000Z

207

Fracture Modeling and Flow Behavior in Shale Gas Reservoirs Using Discrete Fracture Networks  

E-Print Network [OSTI]

Fluid flow process in fractured reservoirs is controlled primarily by the connectivity of fractures. The presence of fractures in these reservoirs significantly affects the mechanism of fluid flow. They have led to problems in the reservoir which...

Ogbechie, Joachim Nwabunwanne

2012-02-14T23:59:59.000Z

208

Estimation of fracture compliance from tubewaves generated at a fracture intersecting a borehole  

E-Print Network [OSTI]

Understanding fracture compliance is important for characterizing fracture networks and for inferring fluid flow in the subsurface. In an attempt to estimate fracture compliance in the field, we developed a new model to ...

Bakku, Sudhish Kumar

2011-01-01T23:59:59.000Z

209

Finite element modeling and experimental study of brittle fracture in tempered martensitic steels for thermonuclear fusion applications.  

E-Print Network [OSTI]

??In this work we have studied brittle fracture in high-chromium reduced activation tempered martensitic steels foreseen as structural materials for thermonuclear fusion reactors. Developing the… (more)

Mueller, Pablo Federico

2009-01-01T23:59:59.000Z

210

Coupled processes in single fractures, double fractures and fractured porous media  

SciTech Connect (OSTI)

The emplacement of a nuclear waste repository in a fractured porous medium provides a heat source of large dimensions over an extended period of time. It also creates a large cavity in the rock mass, changing significantly the stress field. Such major changes induce various coupled thermohydraulic, hydromechanic and hydrochemical transport processes in the environment around a nuclear waste repository. The present paper gives, first, a general overview of the coupled processes involving thermal, mechanical, hydrological and chemical effects. Then investigations of a number of specific coupled processes are described in the context of fluid flow and transport in a single fracture, two intersecting fractures and a fractured porous medium near a nuclear waste repository. The results are presented and discussed.

Tsang, C.F.

1986-12-01T23:59:59.000Z

211

INTERPRETATION OF A HYDRAULIC FRACTURING EXPERIMENT, MONTICELLO, SOUTH CAROLINA  

E-Print Network [OSTI]

Letters INTERPRETATION OF A HYDRAULIC FRACTURING EXPERIMENT,12091 INTERPRETATION OF A HYDRAULIC FRACTURING EXPERIMENT,transient data from a hydraulic fracturing experiment have

Narasimhan, T.N.

2014-01-01T23:59:59.000Z

212

Analysis Of Macroscopic Fractures In Granite In The Hdr Geothermal...  

Open Energy Info (EERE)

between core and acoustic borehole imagery. Detailed structural analysis of the fracture population indicates that fractures are grouped in two principal fractures sets...

213

Fracture Evolution Following a Hydraulic Stimulation within an...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir Fracture Evolution...

214

Aging and Fracture of Human Cortical Bone and Tooth Dentin  

E-Print Network [OSTI]

Mechanistic aspects of fracture and R-curve behavior inof failure of solid biomaterials and bone: `fracture' and `pre- fracture' toughness. Materials Science and Engineering:

Ager III, Joel W.

2008-01-01T23:59:59.000Z

215

DNAPL invasion into a partially saturated dead-end fracture  

E-Print Network [OSTI]

Mobilization in Rock Fractures, Water Resources Research,of DNAPL trapped in dead-end fractures, Geophysical Researchpartially saturated dead-end fracture and a DNAPL lens above

Su, Grace W.; Javandel, Iraj

2008-01-01T23:59:59.000Z

216

Updated fracture incidence rates for the US version of FRAX®  

E-Print Network [OSTI]

presenting with non-vertebral fractures. Osteoporos Int 18:2006) Epidemiology of vertebral fractures: implications forORIGINAL ARTICLE Updated fracture incidence rates for the US

Ettinger, B.; Black, D. M.; Dawson-Hughes, B.; Pressman, A. R.; Melton, L. J.

2010-01-01T23:59:59.000Z

217

Transphyseal Fracture of the Distal Humerus in a Neonate  

E-Print Network [OSTI]

M edicine Transphyseal Fracture of the Distal Humerus in aalignment without osseous fracture and a moderate joint2] revealed a transverse fracture through the distal left

Baker, Annalee M; Methratta, Sosamma T.; Choudhary, Arabinda K

2011-01-01T23:59:59.000Z

218

Fracture opening/propagation behavior and their significance on pressure-time records during hydraulic fracturing  

SciTech Connect (OSTI)

Hydraulic fracturing with constant fluid injection rate was numerically modeled for a pair of rectangular longitudinal fractures intersecting a wellbore in an impermeable rock mass, and numerical calculations have been performed to investigate the relations among the form of pressure-time curves, fracture opening/propagation behavior and permeability of the mechanically closed fractures. The results have shown that both permeability of the fractures and fluid injection rate significantly influence the form of the pressure-time relations on the early stage of fracture opening. Furthermore it has been shown that wellbore pressure during fracture propagation is affected by the pre-existing fracture length.

Takashi Kojima; Yasuhiko Nakagawa; Koji Matsuki; Toshiyuki Hashida

1992-01-01T23:59:59.000Z

219

Creep Failure and Fracture of Polyethylene in Uniaxial J. M. CRISSMAN and L. J. ZAPAS  

E-Print Network [OSTI]

Creep Failure and Fracture of Polyethylene in Uniaxial Extension J. M. CRISSMAN and L. J. ZAPAS conditions of uniaxial creep the frac- ture of high density polyethylene can be categorized as one of three, this phenomenon is known as dead load fatigue. In the case of polyethylene the ultimate fracture can

220

THE ROLE OF CAPILLARY FORCES IN THE NATURAL STATE OF FRACTURED GEOTHERMAL RESERVOIRS  

E-Print Network [OSTI]

THE ROLE OF CAPILLARY FORCES IN THE NATURAL STATE OF FRACTURED GEOTHERMAL RESERVOIRS A REPORT of experiments into the natural state of geothermal reservoirs have been conducted using porous medium models, even though geothermal systems are usually highly fractured. It is unclear whether a porous medium

Stanford University

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Uncertainty in the maximum principal stress estimated from hydraulic fracturing Measurements due to the presence of the induced fracture  

E-Print Network [OSTI]

reopening during hydraulic fracturing stress determinations.Laboratory study of hydraulic fracturing pressure data?Howevaluation of hydraulic fracturing stress measurement

Rutqvist, Jonny; Tsang, Chin-fu; Stephansson, Ove

2000-01-01T23:59:59.000Z

222

Measuring Frac-pack Conductivity at Reservoir Temperature and High Closure Stress  

E-Print Network [OSTI]

fractures packed with high proppant concentrations. Understanding the behavior of the fracture fluid and proppant is critical to pump such a job successfully and to ensure long term productivity from the fracture. A series of laboratory experiments have been...

Fernandes, Preston X.

2010-10-12T23:59:59.000Z

223

Scale-Dependent Fracture-Matrix Interactions And Their Impact on Radionuclide Transport - Final Report  

SciTech Connect (OSTI)

Matrix diffusion and adsorption within a rock matrix are widely regarded as important mechanisms for retarding the transport of radionuclides and other solutes in fractured rock (e.g., Neretnieks, 1980; Tang et al., 1981; Maloszewski and Zuber, 1985; Novakowski and Lapcevic, 1994; Jardine et al., 1999; Zhou and Xie, 2003; Reimus et al., 2003a,b). When remediation options are being evaluated for old sources of contamination, where a large fraction of contaminants reside within the rock matrix, slow diffusion out of the matrix greatly increases the difficulty and timeframe of remediation. Estimating the rates of solute exchange between fractures and the adjacent rock matrix is a critical factor in quantifying immobilization and/or remobilization of DOE-relevant contaminants within the subsurface. In principle, the most rigorous approach to modeling solute transport with fracture-matrix interaction would be based on local-scale coupled advection-diffusion/dispersion equations for the rock matrix and in discrete fractures that comprise the fracture network (Discrete Fracture Network and Matrix approach, hereinafter referred to as DFNM approach), fully resolving aperture variability in fractures and matrix property heterogeneity. However, such approaches are computationally demanding, and thus, many predictive models rely upon simplified models. These models typically idealize fracture rock masses as a single fracture or system of parallel fractures interacting with slabs of porous matrix or as a mobile-immobile or multi-rate mass transfer system. These idealizations provide tractable approaches for interpreting tracer tests and predicting contaminant mobility, but rely upon a fitted effective matrix diffusivity or mass-transfer coefficients. However, because these fitted parameters are based upon simplified conceptual models, their effectiveness at predicting long-term transport processes remains uncertain. Evidence of scale dependence of effective matrix diffusion coefficients obtained from tracer tests highlights this point and suggests that the underlying mechanisms and relationship between rock and fracture properties are not fully understood in large complex fracture networks. In this project, we developed a high-resolution DFN model of solute transport in fracture networks to explore and quantify the mechanisms that control transport in complex fracture networks and how these may give rise to observed scale-dependent matrix diffusion coefficients. Results demonstrate that small scale heterogeneity in the flow field caused by local aperture variability within individual fractures can lead to long-tailed breakthrough curves indicative of matrix diffusion, even in the absence of interactions with the fracture matrix. Furthermore, the temporal and spatial scale dependence of these processes highlights the inability of short-term tracer tests to estimate transport parameters that will control long-term fate and transport of contaminants in fractured aquifers.

Detwiler, Russell

2014-06-30T23:59:59.000Z

224

Monitoring hydraulic fracture growth: Laboratory experiments  

SciTech Connect (OSTI)

The authors carry out small-scale hydraulic fracture experiments to investigate the physics of hydraulic fracturing. The laboratory experiments are combined with time-lapse ultrasonic measurements with active sources using both compressional and shear-wave transducers. For the time-lapse measurements they focus on ultrasonic measurement changes during fracture growth. As a consequence they can detect the hydraulic fracture and characterize its shape and geometry during growth. Hence, this paper deals with fracture characterization using time-lapse acoustic data. Hydraulic fracturing is used in the oil and gas industry to stimulate reservoir production.

Groenenboom, J.; Dam, D.B. van

2000-04-01T23:59:59.000Z

225

Fracture characterization and estimation of fracture porosity of naturally fractured reservoirs with no matrix porosity using stochastic fractal models  

E-Print Network [OSTI]

Determining fracture characteristics at the laboratory scale is a major challenge. It is known that fracture characteristics are scale dependent; as such, the minimum sample size should be deduced in order to scale to reservoir dimensions. The main...

Kim, Tae Hyung

2009-05-15T23:59:59.000Z

226

Integrated 3D Acid Fracturing Model for Carbonate Reservoir Stimulation  

E-Print Network [OSTI]

in integrating fracture propagation, acid transport and dissolution, and well performance models in a seamless fashion for acid fracturing design. In this new approach, the fracture geometry data of a hydraulic fracture is first obtained from commercial models...

Wu, Xi

2014-06-23T23:59:59.000Z

227

VALIDATION OF MASSIVELY PARALLEL SIMULATIONS OF DYNAMIC FRACTURE AND  

E-Print Network [OSTI]

VALIDATION OF MASSIVELY PARALLEL SIMULATIONS OF DYNAMIC FRACTURE AND FRAGMENTATION OF BRITTLE element simulations of dynamic fracture and fragmentation of brittle solids are presented. Fracture the results of massively parallel numerical simulations of dynamic fracture and fragmentation in brittle

Barr, Al

228

Over the past 10 years, there has been a consistent increase in using 3D P-wave data to characterize fractures, which is  

E-Print Network [OSTI]

to characterize fractures, which is critical for ensuring economic oil and gas production in tight formations of otherwise low permeability. Here, we pre- sent a case study of fracture detection using 3D P-wave seismic, of zones of high fracture density that are residual-oil-charged. A major aspect of this study is to compare

Edinburgh, University of

229

EFFECT OF TRITIUM AND DECAY HELIUM ON WELDMENT FRACTURE TOUGHNESS  

SciTech Connect (OSTI)

The fracture toughness data collected in this study are needed to assess the long-term effects of tritium and its decay product on tritium reservoirs. The results show that tritium and decay helium have negative effects on the fracture toughness properties of stainless steel and its weldments. The data and report from this study has been included in a material property database for use in tritium reservoir modeling efforts like the Technology Investment Program ''Lifecycle Engineering for Tritium Reservoirs''. A number of conclusions can be drawn from the data: (1) For unexposed Type 304L stainless steel, the fracture toughness of weldments was two to three times higher than the base metal toughness. (2) Tritium exposure lowered the fracture toughness properties of both base metals and weldments. This was characterized by lower J{sub Q} values and lower J-da curves. (3) Tritium-exposed-and-aged base metals and weldments had lower fracture toughness values than unexposed ones but still retained good toughness properties.

Morgan, M; Scott West, S; Michael Tosten, M

2006-09-26T23:59:59.000Z

230

Hydraulic Fracturing | Open Energy Information  

Open Energy Info (EERE)

Hydraulic Fracturing Hydraulic Fracturing Jump to: navigation, search More info on OpenEI Oil and Gas Gateway Federal Environmental Statues Federal Oil and Gas Statutes Oil and Gas Companies United States Oil and Gas Boards International Oil and Gas Boards Other Information Fracking Regulations by State Wells by State Fracking Chemicals Groundwater Protection Related Reports A Perspective on Health and Natural Gas Operations: A Report for Denton City Council Just the Fracking Facts The Politics of 'Fracking': Regulating Natural Gas Drilling Practices in Colorado and Texas Addressing the Environmental Risks from Shale Gas Development Water Management Technologies Used by Marcellus Shale Gas Producers Methane contamination of drinking wateraccompanying gas-well drilling and hydraulic fracturing

231

Method for directional hydraulic fracturing  

DOE Patents [OSTI]

A method for directional hydraulic fracturing using borehole seals to confine pressurized fluid in planar permeable regions, comprising: placing a sealant in the hole of a structure selected from geologic or cemented formations to fill the space between a permeable planar component and the geologic or cemented formation in the vicinity of the permeable planar component; making a hydraulic connection between the permeable planar component and a pump; permitting the sealant to cure and thereby provide both mechanical and hydraulic confinement to the permeable planar component; and pumping a fluid from the pump into the permeable planar component to internally pressurize the permeable planar component to initiate a fracture in the formation, the fracture being disposed in the same orientation as the permeable planar component.

Swanson, David E. (West St. Paul, MN); Daly, Daniel W. (Crystal, MN)

1994-01-01T23:59:59.000Z

232

Naturally fractured tight gas reservoir detection optimization  

SciTech Connect (OSTI)

The work plan for October 1, 1997 to September 30, 1998 consisted of investigation of a number of topical areas. These topical areas were reported in four quarterly status reports, which were submitted to DOE earlier. These topical areas are reviewed in this volume. The topical areas covered during the year were: (1) Development of preliminary tests of a production method for determining areas of natural fracturing. Advanced Resources has demonstrated that such a relationship exists in the southern Piceance basin tight gas play. Natural fracture clusters are genetically related to stress concentrations (also called stress perturbations) associated with local deformation such a faulting. The mechanical explanation of this phenomenon is that deformation generally initiates at regions where the local stress field is elevated beyond the regional. (2) Regional structural and geologic analysis of the Greater Green River Basin (GGRB). Application of techniques developed and demonstrated during earlier phases of the project for sweet-spot delineation were demonstrated in a relatively new and underexplored play: tight gas from continuous-typeUpper Cretaceous reservoirs of the Greater Green River Basin (GGRB). The effort included data acquisition/processing, base map generation, geophysical and remote sensing analysis and the integration of these data and analyses. (3) Examination of the Table Rock field area in the northern Washakie Basin of the Greater Green River Basin. This effort was performed in support of Union Pacific Resources- and DOE-planned horizontal drilling efforts. The effort comprised acquisition of necessary seismic data and depth-conversion, mapping of major fault geometry, and analysis of displacement vectors, and the development of the natural fracture prediction. (4) Greater Green River Basin Partitioning. Building on fundamental fracture characterization work and prior work performed under this contract, namely structural analysis using satellite and potential field data, the GGRB was divided into partitions that will be used to analyze the resource potential of the Frontier and Mesaverde Upper Cretaceous tight gas play. A total of 20 partitions were developed, which will be instrumental for examining the Upper Cretaceous play potential. (5) Partition Analysis. Resource assessment associated with individual partitions was initiated starting with the Vermilion Sub-basin and the Green River Deep (which include the Stratos well) partitions (see Chapter 5). (6) Technology Transfer. Tech transfer was achieved by documenting our research and presenting it at various conferences.

NONE

1998-11-30T23:59:59.000Z

233

Effect of shear rate on the activity of enzymes used in hydraulic fracture cleanup of tight unconventional reservoirs  

Science Journals Connector (OSTI)

Injection of polymeric solutions in order to propagate a fracture and carry proppants to keep the fracture open is a common practice in hydraulic fracturing of ultra-tight formations. Polymeric fluids open and extend the already existing network of fractures. Considering the low permeability of the formation, small width of the micro-fractures, and the importance of fracture cleanup during the production phase, using breakers is recommended to degrade the more concentrated polymeric fluid and increase the conductivity of the fractures. Enzymes are typically used successfully as breakers for fracturing fluids. In this study, the effect of high shear rates on the activity of enzymes was studied. Enzyme activity decreased at increasing shear rates. However, this activity reduction is reversible. This proves insignificant damage to the enzyme structure due to shear effects. This will assure the activity of the enzymes after reaching the fracture and the more efficient cleanup of the fracture(s). [Received: 31 July 2013; Accepted: 26 January 2014].

Chris Ouyang; Reza Barati

2014-01-01T23:59:59.000Z

234

Fracture behavior of W based materials. Final report  

SciTech Connect (OSTI)

This report describes the results of a program to investigate the fracture properties of tungsten based materials. In particular, the role of crack velocity on crack instability was determined in a W-Fe-Ni-Co ``heavy alloy`` and pure polycrystalline tungsten. A considerable effort was expended on the development of an appropriate crack velocity gage for use on these materials. Having succeeded in that, the gage technology was employed to determine the crack velocity response to the applied level of stress intensity factor at the onset of crack instability in pre-cracked specimens. The results were also correlated to the failure mode observed in two material systems of interest. Major results include: (1) unstable crack velocity measurements on metallic specimens which require high spatial resolution require the use of brittle, insulating substrates, as opposed to the ductile, polymer based substrates employed in low spatial resolution measurements; and (2) brittle failure modes, such as cleavage, are characterized by relatively slow unstable crack velocities while evidence of high degrees of deformation are associated with failures which proceed at high unstable crack velocities. This latter behavior is consistent with the predictions of the modeling of Hack et al and may have a significant impact on the interpretation of fractographs in general.

Hack, J.E. [Yale Univ., New Haven, CT (United States). Dept. of Mechanical Engineering

1991-09-30T23:59:59.000Z

235

SEEPAGE MODEL FOR PA INCLUDING DRIFT COLLAPSE  

SciTech Connect (OSTI)

The purpose of this report is to document the predictions and analyses performed using the seepage model for performance assessment (SMPA) for both the Topopah Spring middle nonlithophysal (Tptpmn) and lower lithophysal (Tptpll) lithostratigraphic units at Yucca Mountain, Nevada. Look-up tables of seepage flow rates into a drift (and their uncertainty) are generated by performing numerical simulations with the seepage model for many combinations of the three most important seepage-relevant parameters: the fracture permeability, the capillary-strength parameter 1/a, and the percolation flux. The percolation flux values chosen take into account flow focusing effects, which are evaluated based on a flow-focusing model. Moreover, multiple realizations of the underlying stochastic permeability field are conducted. Selected sensitivity studies are performed, including the effects of an alternative drift geometry representing a partially collapsed drift from an independent drift-degradation analysis (BSC 2004 [DIRS 166107]). The intended purpose of the seepage model is to provide results of drift-scale seepage rates under a series of parameters and scenarios in support of the Total System Performance Assessment for License Application (TSPA-LA). The SMPA is intended for the evaluation of drift-scale seepage rates under the full range of parameter values for three parameters found to be key (fracture permeability, the van Genuchten 1/a parameter, and percolation flux) and drift degradation shape scenarios in support of the TSPA-LA during the period of compliance for postclosure performance [Technical Work Plan for: Performance Assessment Unsaturated Zone (BSC 2002 [DIRS 160819], Section I-4-2-1)]. The flow-focusing model in the Topopah Spring welded (TSw) unit is intended to provide an estimate of flow focusing factors (FFFs) that (1) bridge the gap between the mountain-scale and drift-scale models, and (2) account for variability in local percolation flux due to stochastic hydrologic properties and flow processes.

C. Tsang

2004-09-22T23:59:59.000Z

236

Nonplanar fracture propagation from a horizontal wellbore: Experimental study  

SciTech Connect (OSTI)

This paper presents experimental results related to hydraulic fracturing of a horizontal well, specifically the nonplanar fracture geometries resulting from fracture initiation and propagation. Experiments were designed to investigate nonplanar fracture geometries. This paper discusses how these nonplanar fractures can be responsible for premature screenout and excessive treatment pressure when a horizontal well is hydraulically fractured. Reasons for unsuccessful hydraulic fracturing treatments of a horizontal well are presented and recommendations to ensure clear communication channels between the wellbore and the fracture are given.

Abass, H.H.; Hedayati, S.; Meadows, D.L.

1996-08-01T23:59:59.000Z

237

Tracer Methods for Characterizing Fracture Stimulation in Engineered...  

Broader source: Energy.gov (indexed) [DOE]

Tracer Methods for Characterizing Fracture Stimulation in Engineered Geothermal Systems (EGS) Tracer Methods for Characterizing Fracture Stimulation in Engineered Geothermal...

238

Dielectric-wall linear accelerator with a high voltage fast rise time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators  

DOE Patents [OSTI]

A dielectric-wall linear accelerator is improved by a high-voltage, fast rise-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface. 12 figs.

Caporaso, G.J.; Sampayan, S.E.; Kirbie, H.C.

1998-10-13T23:59:59.000Z

239

Fracture, aging and disease in bone  

E-Print Network [OSTI]

by enhancing the materials resistance to microstructuralgrowth resistance of microcracking brittle materials. J. Am.resistance to fracture of the Page 4 Fracture, Aging and Disease in Bone underlying material.

Ager, J.W.; Balooch, G.; Ritchie, R.O.

2006-01-01T23:59:59.000Z

240

Modeling of Acid Fracturing in Carbonate Reservoirs  

E-Print Network [OSTI]

The acid fracturing process is a thermal, hydraulic, mechanical, and geochemical (THMG)-coupled phenomena in which the behavior of these variables are interrelated. To model the flow behavior of an acid into a fracture, mass and momentum balance...

Al Jawad, Murtada s

2014-06-05T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Acoustic Character Of Hydraulic Fractures In Granite  

E-Print Network [OSTI]

Hydraulic fractures in homogeneous granitic rocks were logged with conventional acoustic-transit-time, acoustic-waveform, and acoustic-televiewer logging systems. Fractured intervals ranged in depth from 45 to 570m. and ...

Paillet, Frederick I.

1983-01-01T23:59:59.000Z

242

Statistical Modeling of Fracture Toughness Data.  

E-Print Network [OSTI]

??The fracture toughness of the zirconium alloy (Zr-2.5Nb) is an important parameter in determining the flaw tolerance for operation of pressure tubes in reactor. Fracture… (more)

Prakash, Guru

2007-01-01T23:59:59.000Z

243

Surrogate-based optimization of hydraulic fracturing in pre-existing fracture networks  

E-Print Network [OSTI]

Surrogate-based optimization of hydraulic fracturing in pre-existing fracture networks Mingjie Chen Keywords: Hydraulic fracturing Fractal dimension Surrogate model Optimization Global sensitivity a b s t r a c t Hydraulic fracturing has been used widely to stimulate production of oil, natural gas

Lu, Zhiming

244

A model of fracture nucleation, growth and arrest, and consequences for fracture density and scaling  

E-Print Network [OSTI]

A model of fracture nucleation, growth and arrest, and consequences for fracture density; accepted 1 February 2013; published 25 April 2013. [1] In order to improve discrete fracture network (DFN a new DFN modeling based on the evolution of fracture network formation--nucleation, growth, and arrest

Boyer, Edmond

245

FEM Analysis ofFEM Analysis of Deformation and Fracture ofDeformation and Fracture of  

E-Print Network [OSTI]

FEM Analysis ofFEM Analysis of Deformation and Fracture ofDeformation and Fracture of Deformation and Fracture in Polycrystalline -TiAl + 2-Ti3Al Single Crystals #12;Use of -TiAl + 2-Ti3Al Alloys-Temperature Ductility ·Low Ambient-Temperature Fracture Toughness (KIC

Grujicic, Mica

246

Statistical fracture modeling: crack path and fracture criteria with application to homogeneous and  

E-Print Network [OSTI]

Statistical fracture modeling: crack path and fracture criteria with application to homogeneous; accepted 23 January 2002 Abstract Analysis has been performed on fracture initiation near a crack in a brittle material with strength described by Weibull statistics. This nonlocal fracture model allows

Ritchie, Robert

247

A Membrane Deflection Fracture Experiment to Investigate Fracture Toughness of Freestanding MEMS Materials  

E-Print Network [OSTI]

A Membrane Deflection Fracture Experiment to Investigate Fracture Toughness of Freestanding MEMS Materials H.D. Espinosa* and B. Peng ABSTRACT This paper presents a novel Membrane Deflection Fracture Experiment (MDFE) to investigate the fracture toughness of MEMS and other advanced materials in thin film

Espinosa, Horacio D.

248

On modeling hydraulic fracture in proper variables: stiffness, accuracy, sensitivity  

E-Print Network [OSTI]

The problem of hydraulic fracture propagation is considered by using its recently suggested modified formulation in terms of the particle velocity, the opening in the proper degree, appropriate spatial coordinates and $\\varepsilon$-regularization. We show that the formulation may serve for significant increasing the efficiency of numerical tracing the fracture propagation. Its advantages are illustrated by re-visiting the Nordgren problem. It is shown that the modified formulation facilitates (i) possibility to have various stiffness of differential equations resulting after spatial discretization, (ii) obtaining highly accurate and stable numerical results with moderate computational effort, and (iii) sensitivity analysis. The exposition is extensively illustrated by numerical examples.

Mishuris, Gennady; Linkov, Alexander

2012-01-01T23:59:59.000Z

249

Ozone generation by rock fracture: Earthquake early warning?  

SciTech Connect (OSTI)

We report the production of up to 10 ppm ozone during crushing and grinding of typical terrestrial crust rocks in air, O{sub 2} and CO{sub 2} at atmospheric pressure, but not in helium or nitrogen. Ozone is formed by exoelectrons emitted by high electric fields, resulting from charge separation during fracture. The results suggest that ground level ozone produced by rock fracture, besides its potential health hazard, can be used for early warning in earthquakes and other catastrophes, such as landslides or land shifts in excavation tunnels and underground mines.

Baragiola, Raul A.; Dukes, Catherine A.; Hedges, Dawn [Engineering Physics, University of Virginia, Charlottesville, Virginia 22904 (United States)

2011-11-14T23:59:59.000Z

250

Fracturing around excavations in salt at the WIPP  

SciTech Connect (OSTI)

Salt is a plastic material when subjected to high confining pressures. However, salt can behave in a brittle manner with the development of fracturing when subject to deviatoric stresses and low confining pressures. Field data demonstrating brittle behavior have been collected and evaluated at the Waste Isolation Pilot Plant (WIPP), in Carlsbad, New Mexico. This facility is being developed to prove technology for the safe emplacement and storage of transuranic nuclear wastes in deep excavations in salt. Studies using visual, instrumentation and geophysical techniques have been carried out in the underground facility to identify and characterize the types of fractures that develop around openings. 11 refs., 7 figs.

Cook, R.F. (Westinghouse Electric Corp., Carlsbad, NM (USA). Waste Isolation Div.); Roggenthen, W.M. (South Dakota School of Mines and Technology, Rapid City, SD (USA). Dept. of Geology and Geological Engineering)

1991-01-01T23:59:59.000Z

251

Fracture toughness measurements with subsize disk compact specimens  

SciTech Connect (OSTI)

Special fixtures and test methods have been developed for testing small disk compact specimens (1.25 mm diam by 4.6 mm thick). Specimens of European type 316L austenitic stainless steel were irradiated to damage levels of about 3 dpa at nominal irradiation temperatures of either 90 or 250 C and tested over a temperature range from 20 to 250 C. Results show that irradiation to this dose level at these temperatures reduces the fracture toughness but the toughness remains quite high. The toughness decreases as the test temperature increases. Irradiation at 250 C is more damaging than at 90 C, causing larger decreases in the fracture toughness. The testing shows that it is possible to generate useful fracture toughness data with a small disk compact specimens.

Alexander, D.J.

1994-12-31T23:59:59.000Z

252

Using Chemicals to Optimize Conformance Control in Fractured Reservoirs  

SciTech Connect (OSTI)

This report describes work performed during the first year of the project, ''Using Chemicals to Optimize Conformance Control in Fractured Reservoirs.'' This research project has three objectives. The first objective is to develop a capability to predict and optimize the ability of gels to reduce permeability to water more than that to oil or gas. The second objective is to develop procedures for optimizing blocking agent placement in wells where hydraulic fractures cause channeling problems. The third objective is to develop procedures to optimize blocking agent placement in naturally fractured reservoirs. This research project consists of three tasks, each of which addresses one of the above objectives. Our work is directed at both injection wells and production wells and at vertical, horizontal, and highly deviated wells.

Seright, Randall S.; Liang, Jenn-Tai; Schrader, Richard; Hagstrom II, John; Liu, Jin; Wavrik, Kathryn

1999-09-27T23:59:59.000Z

253

The investigation of fracture aperture effect on shale gas transport using discrete fracture model  

Science Journals Connector (OSTI)

Abstract Discrete fracture model (DFM) numerical simulation is used to investigate the shale gas transports in fractured porous media in this paper. A new seepage flow mathematic model, in which flow in fracture meets “Cubic law” and matrix meets “non-Darcy law”, is adopted and fracture aperture effect on the transport behavior is simulated by solving the nonlinear partial differential equations using finite element analysis (FEA). In this DFM, fluid flows into wellbore which is surrounded by impermeable rock matrix is merely through fractures that connect to it. The model is used to simulate a random generated fractures network to study the flow and transport characteristics in fractured porous media (FPM). Several cases with different fracture aperture in same natural fractured model are given. The preliminary simulation results show that both the natural and hydraulic fracture aperture have a significant impact on shale gas migration and production.

Lidong Mi; Hanqiao Jiang; Junjian Li; Tao Li; Ye Tian

2014-01-01T23:59:59.000Z

254

Upscaling solute transport in naturally fractured porous media with the continuous time random walk method  

SciTech Connect (OSTI)

Solute transport in fractured porous media is typically 'non-Fickian'; that is, it is characterized by early breakthrough and long tailing and by nonlinear growth of the Green function-centered second moment. This behavior is due to the effects of (1) multirate diffusion occurring between the highly permeable fracture network and the low-permeability rock matrix, (2) a wide range of advection rates in the fractures and, possibly, the matrix as well, and (3) a range of path lengths. As a consequence, prediction of solute transport processes at the macroscale represents a formidable challenge. Classical dual-porosity (or mobile-immobile) approaches in conjunction with an advection-dispersion equation and macroscopic dispersivity commonly fail to predict breakthrough of fractured porous media accurately. It was recently demonstrated that the continuous time random walk (CTRW) method can be used as a generalized upscaling approach. Here we extend this work and use results from high-resolution finite element-finite volume-based simulations of solute transport in an outcrop analogue of a naturally fractured reservoir to calibrate the CTRW method by extracting a distribution of retention times. This procedure allows us to predict breakthrough at other model locations accurately and to gain significant insight into the nature of the fracture-matrix interaction in naturally fractured porous reservoirs with geologically realistic fracture geometries.

Geiger, S.; Cortis, A.; Birkholzer, J.T.

2010-04-01T23:59:59.000Z

255

Acoustic-emission monitoring during hydraulic fracturing  

SciTech Connect (OSTI)

This paper reports that microseismic events or acoustic emissions associated with hydraulic fracturing are recorded with a borehole seismic tool in a deviated well during multirate injection, shut-in, and flowback. The event locations indicate that fracture orientation, length, and height are compatible with regional stress directions and estimates of the fracture size that are based on pressure decline.

Stewart, L. (Schlumberger-Doll Research (US)); Cassell, B.R. (Schlumberger Wireline Services (US)); Bol, G.M. (Nederlanse Aardolie Mij. B.V. (NL))

1992-06-01T23:59:59.000Z

256

Hydraulic Fracturing in Michigan Integrated Assessment  

E-Print Network [OSTI]

Hydraulic Fracturing in Michigan Integrated Assessment #12;Agenda · Welcome and introduction and timeline · Panel presentation and discussion · Facilitated Q & A · Closing remarks #12;Hydraulic Fracturing · Leverages resources IA BENEFITS Benefits of Integrated Assessment #12;Key Points: · Hydraulic Fracturing (HF

Kamat, Vineet R.

257

Hydraulic Fracture: multiscale processes and moving  

E-Print Network [OSTI]

Hydraulic Fracture: multiscale processes and moving interfaces Anthony Peirce Department Mitchell (UBC) · Ed Siebrits (SLB, Houston) #12;2 Outline · What is a hydraulic fracture? · Scaling Fluid Proppant #12;6 An actual hydraulic fracture #12;7 HF experiment (Jeffrey et al CSIRO) #12;8 1D

Peirce, Anthony

258

Regulation of Hydraulic Fracturing in California  

E-Print Network [OSTI]

APRIL 2013 Regulation of Hydraulic Fracturing in California: A WAsteWAteR And WAteR QuAlity Pe | Regulation of Hydraulic Fracturing in California Wheeler Institute for Water Law & Policy Center for Law #12;Regulation of Hydraulic Fracturing in California | 3Berkeley law | wheeler InstItute for water law

Kammen, Daniel M.

259

Hydraulic Fracture: multiscale processes and moving  

E-Print Network [OSTI]

Hydraulic Fracture: multiscale processes and moving interfaces Anthony Peirce Department Siebrits (SLB, Houston) #12;2 Outline · What is a hydraulic fracture? · Mathematical models of hydraulic fracture · Scaling and special solutions for 1-2D models · Numerical modeling for 2-3D problems

Peirce, Anthony

260

Challenges in Continuum Modelling of Intergranular Fracture  

E-Print Network [OSTI]

Challenges in Continuum Modelling of Intergranular Fracture V. R. Coffman*, J. P. Sethna , A. R-2501, USA Cornell Fracture Group, Rhodes Hall, Cornell University, Ithaca, NY 14853-2501, USA § Department fracture in polycrystals is often simulated by finite elements coupled to a cohesive zone model

Sethna, James P.

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

FRACTURE IN DISORDERED BRITTLE MEDIA A Dissertation  

E-Print Network [OSTI]

FRACTURE IN DISORDERED BRITTLE MEDIA A Dissertation Presented to the Faculty of the Graduate School by Ashivni Shekhawat May 2013 #12;c 2013 Ashivni Shekhawat ALL RIGHTS RESERVED #12;FRACTURE IN DISORDERED- lem of brittle fracture in disordered media. Chapters 2 and 4 are concerned with various aspects

Sethna, James P.

262

FRACTURE TOUGHNESS OF WOOD AND WOOD COMPOSITES  

E-Print Network [OSTI]

FRACTURE TOUGHNESS OF WOOD AND WOOD COMPOSITES DURING CRACK PROPAGATION Noah Matsumoto Structural, USA * Corresponding author: John.Nairn@oregonstate.edu SWST member #12;Fracture Toughness of Wood and Wood Composites During Crack Propagation ABSTRACT The mode I fracture toughness as a function of crack

Nairn, John A.

263

Models for MetaVCeramic Interface Fracture  

E-Print Network [OSTI]

ChaDter 12 Models for MetaVCeramic Interface Fracture ZHIGANG SUO C. FONG SHIH Metal shortcomingthat haslimited their wide- spread use-their tendency to fracture easily. In many systems, the low on interface fracture are reviewed in this chapter. With few exceptions, attention is limited to continuum

Suo, Zhigang

264

Introduction That fracture is governed by processes  

E-Print Network [OSTI]

Introduction That fracture is governed by processes occurring over a wide range of length scales has been recognized since the earli- est developments of modern fracture me- chanics. Griffith's study by several decades the first at- tempts to apply atomistically grounded traction-separation laws to fracture

Beltz, Glenn E.

265

LA-13194-MS Fracture Characterization of the  

E-Print Network [OSTI]

LA-13194-MS Fracture Characterization of the Bandelier Tuff in OU-1098 (TA-2 and TA-41) LosN A T I technical correctness. #12;Fracture Characterization of the Bandelier Tuff in OU-1098 (TA-2 and TA-41 Los Alamos, New Mexico 87545 #12;1 Fracture Characterization of the Bandelier Tuff in OU-1098 (TA-2

266

Experiences with aquifer testing and analysis in fractured low-permeability sedimentary rocks exhibiting nonradial pumping response  

SciTech Connect (OSTI)

Multiple-well aquifer pumping tests have been used successfully to measure the bulk hydraulic properties of limestone and shale formations of the Conasauga Group of East Tennessee and to define directional components in transmissivity associated with joints and small-scale folds. This experience demonstrates that multiple-well pumping tests can be used to measure the characteristics of low-permeability fractured rocks, and it illustrates the application of data interpretation techniques that are based on models of nonradial aquifer pumping response. Analytical models that have been used to interpret pumping test data include models for simple anisotropic response and for complex pumping response in an anisotropic aquifer intersected by a single high-conductivity vertical fracture. Comparisons of results obtained using nonradial flow methods with those obtained using traditional (radial flow) analytical methods indicate that the error from radial flow methods is generally less than an order of magnitude, an insignificant error in most low-permeability settings. However, the nonradial flow methods provide much more information on structural controls on groundwater movement. Special challenges encountered in conducting aquifer pumping tests in this hydrogeologic environment include selecting a pumping rate that can be sustained after fracture storage is depleted and laying out a test configuration that is consistent with the test geometry required by the nonradial flow interpretive models. Effective test design and data interpretation thus require extensive insight into site geology.

Smith, E.D.; Vaughan, N.D.

1985-01-01T23:59:59.000Z

267

Discrete element modeling of rock deformation, fracture network development and permeability evolution under hydraulic stimulation  

SciTech Connect (OSTI)

Key challenges associated with the EGS reservoir development include the ability to reliably predict hydraulic fracturing and the deformation of natural fractures as well as estimating permeability evolution of the fracture network with time. We have developed a physics-based rock deformation and fracture propagation simulator by coupling a discrete element model (DEM) for fracturing with a network flow model. In DEM model, solid rock is represented by a network of discrete elements (often referred as particles) connected by various types of mechanical bonds such as springs, elastic beams or bonds that have more complex properties (such as stress-dependent elastic constants). Fracturing is represented explicitly as broken bonds (microcracks), which form and coalesce into macroscopic fractures when external and internal load is applied. The natural fractures are represented by a series of connected line segments. Mechanical bonds that intersect with such line segments are removed from the DEM model. A network flow model using conjugate lattice to the DEM network is developed and coupled with the DEM. The fluid pressure gradient exerts forces on individual elements of the DEM network, which therefore deforms the mechanical bonds and breaks them if the deformation reaches a prescribed threshold value. Such deformation/fracturing in turn changes the permeability of the flow network, which again changes the evolution of fluid pressure, intimately coupling the two processes. The intimate coupling between fracturing/deformation of fracture networks and fluid flow makes the meso-scale DEM- network flow simulations necessary in order to accurately evaluate the permeability evolution, as these methods have substantial advantages over conventional continuum mechanical models of elastic rock deformation. The challenges that must be overcome to simulate EGS reservoir stimulation, preliminary results, progress to date and near future research directions and opportunities will be discussed. Methodology for coupling the DEM model with continuum flow and heat transport models will also be discussed.

Shouchun Deng; Robert Podgorney; Hai Huang

2011-02-01T23:59:59.000Z

268

Capillary fracture of soft gels  

E-Print Network [OSTI]

A liquid droplet resting on a soft gel substrate can deform that substrate to the point of material failure, whereby fractures develop on the gel surface that propagate outwards from the contact-line in a starburst pattern. In this paper, we characterize i) the initiation process in which the number of arms in the starburst is controlled by the ratio of surface tension contrast to the gel's elastic modulus and ii) the propagation dynamics showing that once fractures are initiated they propagate with a universal power law $L\\propto t^{3/4}$. We develop a model for crack initiation by treating the gel as a linear elastic solid and computing the deformations within the substrate from the liquid/solid wetting forces. The elastic solution shows that both the location and magnitude of the wetting forces are critical in providing a quantitative prediction for the number of fractures and, hence, an interpretation of the initiation of capillary fractures. This solution also reveals that the depth of the gel is an impo...

Bostwick, Joshua B

2013-01-01T23:59:59.000Z

269

Relative Permeability of Fractured Rock  

E-Print Network [OSTI]

, and by the Department of Petroleum Engineering, Stanford University Stanford Geothermal Program Interdisciplinary Research in Engineering and Earth Sciences STANFORD UNIVERSITY Stanford, California #12;#12;v Abstract fractures and various fluids have yielded different relative permeability-saturation relations. This study

Stanford University

270

Modifications of Carbonate Fracture Hydrodynamic Properties by CO{sub 2}-Acidified Brine Flow  

SciTech Connect (OSTI)

Acidic reactive flow in fractures is relevant in subsurface activities such as CO{sub 2} geological storage and hydraulic fracturing. Understanding reaction-induced changes in fracture hydrodynamic properties is essential for predicting subsurface flows such as leakage, injectability, and fluid production. In this study, x-ray computed tomography scans of a fractured carbonate caprock were used to create three dimensional reconstructions of the fracture before and after reaction with CO{sub 2}-acidified brine (Ellis et al., 2011, Greenhouse Gases: Sci. Technol., 1:248-260). As expected, mechanical apertures were found to increase substantially, doubling and even tripling in some places. However, the surface geometry evolved in complex ways including ‘comb-tooth’ structures created from preferential dissolution of calcite in transverse sedimentary bands, and the creation of degraded zones, i.e. porous calcite-depleted areas on reacted fracture surfaces. These geometric alterations resulted in increased fracture roughness, as measured by surface Z{sub 2} parameters and fractal dimensions D{sub f}. Computational fluid dynamics (CFD) simulations were conducted to quantify the changes in hydraulic aperture, fracture transmissivity and permeability. The results show that the effective hydraulic apertures are smaller than the mechanical apertures, and the changes in hydraulic apertures are nonlinear. Overestimation of flow rate by a factor of two or more would be introduced if fracture hydrodynamic properties were based on mechanical apertures, or if hydraulic aperture is assumed to change proportionally with mechanical aperture. The differences can be attributed, in part, to the increase in roughness after reaction, and is likely affected by contiguous transverse sedimentary features. Hydraulic apertures estimated by the 1D statistical model and 2D local cubic law (LCL) model are consistently larger than those calculated from the CFD simulations. In addition, a novel ternary segmentation method was devised to handle the degraded zones, allowing for a bounding analysis of the effects on hydraulic properties. We found that the degraded zones account for less than 15% of the fracture volume, but cover 70% to 80% of the fracture surface. When the degraded zones are treated as part of the fracture, the fracture transmissivities are two to four times larger because the fracture surfaces after reaction are not as rough as they would be if one considers the degraded zone as part of the rock. Therefore, while degraded zones created during geochemical reactions may not significantly increase mechanical aperture, this type of feature cannot be ignored and should be treated with prudence when predicting fracture hydrodynamic properties.

Deng, Hang; Ellis, Brian R.; Peters, Catherine A.; Fitts, Jeffrey P.; Crandall, Dustin; Bromhal, Grant S.

2013-08-01T23:59:59.000Z

271

Geomechanical Simulation of Fluid-Driven Fractures  

SciTech Connect (OSTI)

The project supported graduate students working on experimental and numerical modeling of rock fracture, with the following objectives: (a) perform laboratory testing of fluid-saturated rock; (b) develop predictive models for simulation of fracture; and (c) establish educational frameworks for geologic sequestration issues related to rock fracture. These objectives were achieved through (i) using a novel apparatus to produce faulting in a fluid-saturated rock; (ii) modeling fracture with a boundary element method; and (iii) developing curricula for training geoengineers in experimental mechanics, numerical modeling of fracture, and poroelasticity.

Makhnenko, R.; Nikolskiy, D.; Mogilevskaya, S.; Labuz, J.

2012-11-30T23:59:59.000Z

272

CONSTRAINT EFFECT IN FRACTURE WHAT IS IT  

SciTech Connect (OSTI)

The meaning of the phrase 'constraint effect in fracture' has changed in the past two decades from 'contained plasticity' to a broader description of 'dependence of fracture toughness value on geometry of test specimen or structure'. This paper will first elucidate the fundamental mechanics reasons for the apparent 'constraint effects in fracture', followed by outlining a straightforward approach to overcoming this problem in both brittle (elastic) and ductile (elastic-plastic) fracture. It is concluded by discussing the major difference in constraint effect on fracture event in elastic and elastic-plastic materials.

Lam, P; Prof. Yuh J. Chao, P

2008-10-29T23:59:59.000Z

273

Structural Settings Of Hydrothermal Outflow- Fracture Permeability  

Open Energy Info (EERE)

Settings Of Hydrothermal Outflow- Fracture Permeability Settings Of Hydrothermal Outflow- Fracture Permeability Maintained By Fault Propagation And Interaction Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Structural Settings Of Hydrothermal Outflow- Fracture Permeability Maintained By Fault Propagation And Interaction Details Activities (1) Areas (1) Regions (0) Abstract: Hydrothermal outflow occurs most commonly at the terminations of individual faults and where multiple faults interact. These areas of fault propagation and interaction are sites of elevated stress termed breakdown regions. Here, stress concentrations cause active fracturing and continual re-opening of fluid-flow conduits, permitting long-lived hydrothermal flow despite potential clogging of fractures due to mineral precipitation. As

274

Microseismic Tracer Particles for Hydraulic Fracturing  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Microseismic Tracer Particles for Hydraulic Fracturing Microseismic Tracer Particles for Hydraulic Fracturing Microseismic Tracer Particles for Hydraulic Fracturing Scientists at Los Alamos National Laboratory have developed a method by which microseismic events can be discriminated/detected that correspond to only the portion of the hydraulic fracture that contains the proppant material and can be expected to be conductive to the flow of oil and gas. July 3, 2013 Microseismic Tracer Particles for Hydraulic Fracturing Figure 1: A graph of ionic conductivity as a function of temperature for the anti-perovskite Li3OCl. Available for thumbnail of Feynman Center (505) 665-9090 Email Microseismic Tracer Particles for Hydraulic Fracturing Applications: Oil and gas production Geophysical exploration Benefits: Tracks the disposition of material in a hydraulic fracturing

275

Experience proves forced fracture closure works  

SciTech Connect (OSTI)

Forced closure, or perhaps better-named ``reverse gravel packing,`` of fractures immediately following hydraulic fracturing with proppant and gelled fluids is a technique which, with rare exception, can be extremely beneficial to the success of almost every hydraulic fracture treatment. By proper planning of the rig-up to allow immediate flow-back, substantial quantities of polymer and load fluid can be removed while simultaneously negating undesirable proppant settling within fractures in the near wellbore area. Fracture smearing (dilution of proppant into an extending fracture) after shutdown can be negated. And in most cases, proppant production from the formation can be reduced. Discussions in the article explain why Ely and Associates has the confidence to make these claims after extensive hydraulic fracturing experience in many geographical areas.

Ely, J.W. [John Ely and Associates, Inc., Houston, TX (United States)

1996-01-01T23:59:59.000Z

276

Interaction between Injection Points during Hydraulic Fracturing  

E-Print Network [OSTI]

We present a model of the hydraulic fracturing of heterogeneous poroelastic media. The formalism is an effective continuum model that captures the coupled dynamics of the fluid pressure and the fractured rock matrix and models both the tensile and shear failure of the rock. As an application of the formalism, we study the geomechanical stress interaction between two injection points during hydraulic fracturing (hydrofracking) and how this interaction influences the fracturing process. For injection points that are separated by less than a critical correlation length, we find that the fracturing process around each point is strongly correlated with the position of the neighboring point. The magnitude of the correlation length depends on the degree of heterogeneity of the rock and is on the order of 30-45 m for rocks with low permeabilities. In the strongly correlated regime, we predict a novel effective fracture-force that attracts the fractures toward the neighboring injection point.

Hals, Kjetil M D

2012-01-01T23:59:59.000Z

277

Multicomponent fluid flow by discontinuous Galerkin and mixed methods in unfractured and fractured media  

E-Print Network [OSTI]

. Numerical examples in unfractured and fractured media illustrate the efficiency and robustness in gas-condensate reservoirs), hydrology and geochemical engineering (contamination of groundwater field, sharp variations in the rock properties, and high nonlinearity of the multicomponent system due

Firoozabadi, Abbas

278

A decision-analytic approach to predict state regulation of hydraulic fracturing  

Science Journals Connector (OSTI)

Horizontal drilling and high-volume hydraulic fracturing, collectively known as ‘fracking,’ opened up the possibility for new ... the globe. While not a novel technology, fracking has taken off in the USA and...1

Igor Linkov; Benjamin Trump; David Jin; Marcin Mazurczak…

2014-08-01T23:59:59.000Z

279

Pressure Ulcers and Prolonged Hospital Stay in Hip Fracture Patients Affected by Time-to-Surgery  

Science Journals Connector (OSTI)

Hip fractures are associated with high morbidity. Pressure ulcer formation after hip surgery is often related to delayed patient mobilization. The objectives of this study were to determine whether time-to-sur...

Leonard M. F. Rademakers MD; Tryfon Vainas…

2007-06-01T23:59:59.000Z

280

Enhanced oil recovery through water imbibition in fractured reservoirs using Nuclear Magnetic Resonance  

E-Print Network [OSTI]

Conventional waterflooding methods of oil recovery are difficult to apply when reservoirs show evidence of natural fractures, because injected water advances through paths of high permeability, and oil trapped in the rock matrix system...

Hervas Ordonez, Rafael Alejandro

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Correlations to predict frictional pressure loss of hydraulic-fracturing slurry in coiled tubing  

SciTech Connect (OSTI)

Compared with conventional-tubing fracturing, coiled-tubing (CT) fracturing has several advantages. CT fracturing has become an effective stimulation technique for multizone oil and gas wells. It is also an attractive production-enhancement method for multiseam coalbed-methane wells, and wells with bypassed zones. The excessive frictional pressure loss through CT has been a concern in fracturing. The small diameter of the string limits the cross-sectional area open to flow. Furthermore, the tubing curvature causes secondary flow and results in extra flow resistance. This increased frictional pressure loss results in high surface pumping pressure. The maximum possible pump rate and sand concentration, therefore, have to be reduced. To design a CT fracturing job properly, it is essential to predict the frictional pressure loss through the tubing accurately. This paper presents correlations for the prediction of frictional pressure loss of fracturing slurries in straight tubing and CT. They are developed on the basis of full-scale slurry-flow tests with 11/2-in. CT and slurries prepared with 35 lbm/1,000 gal of guar gel. The extensive experiments were conducted at the full-scale CT-flow test facility. The proposed correlations have been verified with the experimental data and actual field CT-fracturing data. Case studies of wells recently fractured are provided to demonstrate the application of the correlations. The correlations will be useful to the CT engineers in their hydraulics design calculations.

Shah, S.; Zhoi, Y.X.; Bailey, M.; Hernandez, J. [University of Oklahoma, Norman, OK (United States)

2009-08-15T23:59:59.000Z

282

Multi-Site Application of the Geomechanical Approach for Natural Fracture Exploration  

SciTech Connect (OSTI)

In order to predict the nature and distribution of natural fracturing, Advanced Resources Inc. (ARI) incorporated concepts of rock mechanics, geologic history, and local geology into a geomechanical approach for natural fracture prediction within mildly deformed, tight (low-permeability) gas reservoirs. Under the auspices of this project, ARI utilized and refined this approach in tight gas reservoir characterization and exploratory activities in three basins: the Piceance, Wind River and the Anadarko. The primary focus of this report is the knowledge gained on natural fractural prediction along with practical applications for enhancing gas recovery and commerciality. Of importance to tight formation gas production are two broad categories of natural fractures: (1) shear related natural fractures and (2) extensional (opening mode) natural fractures. While arising from different origins this natural fracture type differentiation based on morphology is sometimes inter related. Predicting fracture distribution successfully is largely a function of collecting and understanding the available relevant data in conjunction with a methodology appropriate to the fracture origin. Initially ARI envisioned the geomechanical approach to natural fracture prediction as the use of elastic rock mechanics methods to project the nature and distribution of natural fracturing within mildly deformed, tight (low permeability) gas reservoirs. Technical issues and inconsistencies during the project prompted re-evaluation of these initial assumptions. ARI's philosophy for the geomechanical tools was one of heuristic development through field site testing and iterative enhancements to make it a better tool. The technology and underlying concepts were refined considerably during the course of the project. As with any new tool, there was a substantial learning curve. Through a heuristic approach, addressing these discoveries with additional software and concepts resulted in a stronger set of geomechanical tools. Thus, the outcome of this project is a set of predictive tools with broad applicability across low permeability gas basins where natural fractures play an important role in reservoir permeability. Potential uses for these learnings and tools range from rank exploration to field-development portfolio management. Early incorporation of the permeability development concepts presented here can improve basin assessment and direct focus to the high potential areas within basins. Insight into production variability inherent in tight naturally fractured reservoirs leads to improved wellbore evaluation and reduces the incidence of premature exits from high potential plays. A significant conclusion of this project is that natural fractures, while often an important, overlooked aspect of reservoir geology, represent only one aspect of the overall reservoir fabric. A balanced perspective encompassing all aspects of reservoir geology will have the greatest impact on exploration and development in the low permeability gas setting.

R. L. Billingsley; V. Kuuskraa

2006-03-31T23:59:59.000Z

283

THE STATE OF THE ART OF NUMERICAL MODELING OF THERMOHYDROLOGIC FLOW IN FRACTURED ROCK MASSES  

E-Print Network [OSTI]

improving production by hydraulic fracturing 8 the focus otfor fractures. (d) Hydraulic Fracturing: The model has been

Wang, J.S.Y.

2013-01-01T23:59:59.000Z

284

Irradiation Effects on Human Cortical Bone Fracture Behavior  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Irradiation Effects on Human Cortical Bone Fracture Behavior Print Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking place on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and/or tomography, is a popular method of investigating micrometer deformation and fracture behavior in bone. However, the role that irradiation plays in these high-exposure experiments, and how it affects the properties of bone tissue, are not yet fully understood. A team of researchers led by Robert O. Ritchie at the Lawrence Berkeley National Laboratory and the University of California, Berkeley used synchrotron radiation micro-tomography at Advanced Light Source Beamline 8.3.2 to investigate changes in crack path and toughening mechanisms in human cortical bone with increased exposure to radiation, finding that exposure to high levels of irradiation can lead to drastic losses in strength, ductility, and toughness.

285

Irradiation Effects on Human Cortical Bone Fracture Behavior  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Irradiation Effects on Human Cortical Bone Fracture Behavior Print Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking place on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and/or tomography, is a popular method of investigating micrometer deformation and fracture behavior in bone. However, the role that irradiation plays in these high-exposure experiments, and how it affects the properties of bone tissue, are not yet fully understood. A team of researchers led by Robert O. Ritchie at the Lawrence Berkeley National Laboratory and the University of California, Berkeley used synchrotron radiation micro-tomography at Advanced Light Source Beamline 8.3.2 to investigate changes in crack path and toughening mechanisms in human cortical bone with increased exposure to radiation, finding that exposure to high levels of irradiation can lead to drastic losses in strength, ductility, and toughness.

286

Irradiation Effects on Human Cortical Bone Fracture Behavior  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Irradiation Effects on Human Irradiation Effects on Human Cortical Bone Fracture Behavior Irradiation Effects on Human Cortical Bone Fracture Behavior Print Wednesday, 28 July 2010 00:00 Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking place on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and/or tomography, is a popular method of investigating micrometer deformation and fracture behavior in bone. However, the role that irradiation plays in these high-exposure experiments, and how it affects the properties of bone tissue, are not yet fully understood. A team of researchers led by Robert O. Ritchie at the Lawrence Berkeley National Laboratory and the University of California, Berkeley used synchrotron radiation micro-tomography at Advanced Light Source Beamline 8.3.2 to investigate changes in crack path and toughening mechanisms in human cortical bone with increased exposure to radiation, finding that exposure to high levels of irradiation can lead to drastic losses in strength, ductility, and toughness.

287

Irradiation Effects on Human Cortical Bone Fracture Behavior  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Irradiation Effects on Human Cortical Bone Fracture Behavior Print Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking place on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and/or tomography, is a popular method of investigating micrometer deformation and fracture behavior in bone. However, the role that irradiation plays in these high-exposure experiments, and how it affects the properties of bone tissue, are not yet fully understood. A team of researchers led by Robert O. Ritchie at the Lawrence Berkeley National Laboratory and the University of California, Berkeley used synchrotron radiation micro-tomography at Advanced Light Source Beamline 8.3.2 to investigate changes in crack path and toughening mechanisms in human cortical bone with increased exposure to radiation, finding that exposure to high levels of irradiation can lead to drastic losses in strength, ductility, and toughness.

288

Irradiation Effects on Human Cortical Bone Fracture Behavior  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Irradiation Effects on Human Cortical Bone Fracture Behavior Print Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking place on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and/or tomography, is a popular method of investigating micrometer deformation and fracture behavior in bone. However, the role that irradiation plays in these high-exposure experiments, and how it affects the properties of bone tissue, are not yet fully understood. A team of researchers led by Robert O. Ritchie at the Lawrence Berkeley National Laboratory and the University of California, Berkeley used synchrotron radiation micro-tomography at Advanced Light Source Beamline 8.3.2 to investigate changes in crack path and toughening mechanisms in human cortical bone with increased exposure to radiation, finding that exposure to high levels of irradiation can lead to drastic losses in strength, ductility, and toughness.

289

Colloid migration in fractured media  

SciTech Connect (OSTI)

Field studies at the Nevada Test Site by researchers at Lawrence Livermore National Laboratory have demonstrated that radionuclides are being transported by colloidal material suspended in groundwater. This observation is counter to most predictions from contaminant transport models because the models assume adsorbed species are immobile. The purpose of this research is to quantify the transport processes for colloidal materials and develop the mechanistic understanding necessary to predict radionuclide transport in fractured media. There were three areas of investigation during this year that have addressed these issues: chemical control of colloid deposition on clean mineral surfaces, colloid accumulation on fracture surfaces, and the influence of deposited colloids on colloid and tracer migration. 7 refs.

Hunt, J.R. (California Univ., Berkeley, CA (USA). Dept. of Civil Engineering)

1989-09-15T23:59:59.000Z

290

Acoustic Emission in a Fluid Saturated Hetergeneous Porous Layer with Application to Hydraulic Fracture  

E-Print Network [OSTI]

responses during hydraulic fracturing, and aid developmentFracture Monitoring Hydraulic fracturing is a method forfluids" used for hydraulic fracturing, the above frequencies

Nelson, J.T.

2009-01-01T23:59:59.000Z

291

Fracture of irradiated zircaloy-2  

Science Journals Connector (OSTI)

This paper summarizes the results of a series of investigations to evaluate the fracture behavior of Zircaloy-2 as influenced by BWR and PWR conditions. The results show that the response of the fracture toughness of Zircaloy-2 to various combinations of cold work, hydrogen content and neutron fluence in hot pressurized water is characterized by embrittlement to a point where saturation in the fracture toughness is attained. Further in-reactor exposure beyond this saturation point appears to have no effect on toughness although other mechanical properties such as flow stress continue to change. In addition, anisotropy in the toughness of rolled plate material, evident in the unirradiated condition, is retained during in-reactor exposure and after increases in hydrogen content. Several processes are thought to be contributing to the toughness of Zircaloy-2 during irradiation. The reduction in toughness at low exposures must result from defect interactions with the deformation modes and the formation of the brittle hydride phase. However, the occurrence of saturation is not explained by these mechanisms in view of data on other mechanical properties and corrosion rates. It is suggested that the difference in the conditions for initiation of slip and twinning would indicate that the twinning component of deformation is not reduced by irradiation damage as much as the slip component. Saturation is, therefore, interprétable on the basis that twinning plays a major role in the crack tip plastic zone after irradiation. Additional study of the importance of twinning in determining the toughness of Zircaloy-2 was attempted by examining the relationship between texture and the anisotropy in fracture toughness. A correlation is shown to exist between the crack tip shear stresses resolved on the 1121 twin system and the toughness anisotropy.

R.G. Hoagland; R.G. Rowe

1969-01-01T23:59:59.000Z

292

Unsaturated fractured rock characterization methods and data sets at the Apache Leap Tuff Site  

SciTech Connect (OSTI)

Performance assessment of high-level nuclear waste containment feasibility requires representative values of parameters as input, including parameter moments, distributional characteristics, and covariance structures between parameters. To meet this need, characterization methods and data sets for interstitial, hydraulic, pneumatic and thermal parameters for a slightly welded fractured tuff at the Apache Leap Tuff Site situated in central Arizona are reported in this document. The data sets include the influence of matric suction on measured parameters. Spatial variability is investigated by sampling along nine boreholes at regular distances. Laboratory parameter estimates for 105 core segments are provided, as well as field estimates centered on the intervals where the core segments were collected. Measurement uncertainty is estimated by repetitively testing control samples. 31 refs., 10 figs., 21 tabs.

Rasmussen, T.C.; Evans, D.D.; Sheets, P.J.; Blanford, J.H. [Arizona Univ., Tucson, AZ (USA). Dept. of Hydrology and Water Resources

1990-08-01T23:59:59.000Z

293

Geothermal fracture stimulation technology. Volume III. Geothermal fracture fluids  

SciTech Connect (OSTI)

A detailed study of all available and experimental frac fluid systems is presented. They have been examined and tested for physical properties that are important in the stimulation of hot water geothermal wells. These fluids consist of water-based systems containing high molecular weight polymers in the uncrosslinked and crosslinked state. The results of fluid testing for many systems are summarized specifically at geothermal conditions or until breakdown occurs. Some of the standard tests are ambient viscosity, static aging, high temperature viscosity, fluid-loss testing, and falling ball viscosity at elevated temperatures and pressures. Results of these tests show that unalterable breakdown of the polymer solutions begins above 300/sup 0/F. This continues at higher temperatures with time even if stabilizers or other high temperature additives are included.

Not Available

1981-01-01T23:59:59.000Z

294

Using seismic tomography to characterize fracture systems induced by hydraulic fracturing  

SciTech Connect (OSTI)

Microearthquakes induced by hydraulic fracturing have been studied by many investigators to characterize fracture systems created by the fracturing process and to better understand the locations of energy resources in the earth`s subsurface. The pattern of the locations often contains a great deal of information about the fracture system stimulated during the hydraulic fracturing. Seismic tomography has found applications in many areas for characterizing the subsurface of the earth. It is well known that fractures in rock influence both the P and S velocities of the rock. The influence of the fractures is a function of the geometry of the fractures, the apertures and number of fractures, and the presence of fluids in the fractures. In addition, the temporal evolution of the created fracture system can be inferred from the temporal changes in seismic velocity and the pattern of microearthquake locations. Seismic tomography has been used to infer the spatial location of a fracture system in a reservoir that was created by hydraulic fracturing.

Fehler, M.; Rutledge, J.

1995-01-01T23:59:59.000Z

295

Hydraulic-fracture growth in dipping anisotropic strata as viewed through the surface deformation field  

SciTech Connect (OSTI)

In 1983 and 1984 Oak Rdige National Laboratory conducted a series of precision ground deformation measurements before, during, and after the generation of several large hydraulic fractures in a dipping member of the Cambrian Conasauga Shale. Each fracture was produced by the injection of approximately 500,000 L of slurry on a single day. Injection depth was 300 m. Leveling surveys were run several days before and several days after the injections. An array of eight high-precision borehole tiltmeters monitored ground deformations continuously for a period of several weeks. Analysis of the leveling and the tilt measurements revealed surface uplifts as great as 25 mm and tilts of tens of microradians during each injection. Furthermore, partial recovery (subsidence) of the ground took place during the days following an injection, accompanied by shifts in the position of maximum resultant uplift. Interpretation of the tilt measurements is consistent with stable widening and extension of hydraulic fractures with subhorizontal orientations. Comparison of the measured tilt patterns with fracture orientations established from logging of observation wells suggests that shearing parallel to the fracture planes accompanied fracture dilation. This interpretation is supported by measured tilts and ground uplifts that were as much as 100 percent greater than those expected from fracture dilation alone. Models of elastically anisotropic overburden rock do not explain the measured tilt patterns in the absence of shear stresses in the fracture planes. This work represents the first large-scale hydraulic-fracturing experiment in which the possible effects of material anisotropy and fracture-parallel shears have been measured and interpreted.

Holzhausen, G.R.; Haase, C.S.; Stow, S.H.; Gazonas, G.

1985-01-01T23:59:59.000Z

296

Biochemical Markers of Bone Turnover in Percutaneous Vertebroplasty for Osteoporotic Compression Fracture  

SciTech Connect (OSTI)

Purpose. To evaluate relationships between biochemical markers of bone turnover, bone mineral density, and new compression fractures following vertebroplasty. Methods. Initially, we enrolled 30 consecutive patients with vertebral compression fractures caused by osteoporosis. Twenty-three of the 30 patients visited our hospital for follow-up examinations for more than 4 weeks after vertebroplasty. The patients were divided into two groups: patients with new fractures (group F) and patients with no new fractures (group N). We analyzed differences in the following parameters between these two groups: serum bone alkaline phosphatase, urinary crosslinked N-telopeptide of type I collagen, urinary deoxypyridinoline, and bone mineral density. Next, the patients were divided into another two groups: patients with higher risk (group H: urinary crosslinked N-telopeptide of type I collagen >54.3 nmol BCE/mmol Cr or urinary deoxypyridinoline >7.6 nmol/mmol Cr, and serum bone alkaline phosphatase <29.0 U/l) and patients with lower risk (group L). We analyzed the difference in the rate of new fractures between these two groups. Results. We identified 9 new fractures in 7 patients. There were no significant differences between groups F and N. We identified 5 new fractures in 3 of the 4 patients in group H, and 4 new fractures in 4 of the 19 patients in group L. There was a significant difference in the rate of new fractures between groups H and L. Conclusions. A combination of high levels of bone resorption markers and normal levels of bone formation markers may be associated with increased risk of new recurrent fractures after percutaneous vertebroplasty.

Komemushi, Atsushi, E-mail: kome64@yo.rim.or.jp; Tanigawa, Noboru; Kariya, Shuji; Kojima, Hiroyuki; Shomura, Yuzo; Tokuda, Takanori; Nomura, Motoo; Terada, Jiro; Kamata, Minoru; Sawada, Satoshi [Kansai Medical University, Department of Radiology (Japan)

2008-03-15T23:59:59.000Z

297

Apparatus and method for monitoring underground fracturing  

DOE Patents [OSTI]

An apparatus and method for measuring deformation of a rock mass around the vicinity of a fracture, commonly induced by hydraulic fracturing is provided. To this end, a well is drilled offset from the proposed fracture region, if no existing well is present. Once the well is formed to a depth approximately equal or exceeding the depth of the proposed fracture, a plurality of inclinometers, for example tiltmeters, are inserted downhole in the well. The inclinometers are located both above and below the approximate depth of the proposed fracture. The plurality of inclinometers may be arranged on a wireline that may be retrieved from the downhole portion of the well and used again or, alternatively, the inclinometers may be cemented in place. In either event, the inclinometers are used to measure the deformation of the rock around the induced fracture. 13 figs.

Warpinski, N.R.; Steinfort, T.D.; Branagan, P.T.; Wilmer, R.H.

1999-08-10T23:59:59.000Z

298

Apparatus and method for monitoring underground fracturing  

DOE Patents [OSTI]

An apparatus and method for measuring deformation of a rock mass around the vicinity of a fracture, commonly induced by hydraulic fracturing is provided. To this end, a well is drilled offset from the proposed fracture region, if no existing well is present. Once the well is formed to a depth approximately equal or exceeding the depth of the proposed fracture, a plurality of inclinometers, for example tiltmeters, are inserted downhole in the well. The inclinometers are located both above and below the approximate depth of the proposed fracture. The plurality of inclinometers may be arranged on a wireline that may be retrieved from the downhole portion of the well and used again or, alternatively, the inclinometers may be cemented in place. In either event, the inclinometers are used to measure the deformation of the rock around the induced fracture.

Warpinski, Norman R. (Albuquerque, NM); Steinfort, Terry D. (Tijeras, NM); Branagan, Paul T. (Las Vegas, NV); Wilmer, Roy H. (Las Vegas, NV)

1999-08-10T23:59:59.000Z

299

Standard practice for prediction of the long-term behavior of materials, including waste forms, used in engineered barrier systems (EBS) for geological disposal of high-level radioactive waste  

E-Print Network [OSTI]

1.1 This practice describes test methods and data analyses used to develop models for the prediction of the long-term behavior of materials, such as engineered barrier system (EBS) materials and waste forms, used in the geologic disposal of spent nuclear fuel (SNF) and other high-level nuclear waste in a geologic repository. The alteration behavior of waste form and EBS materials is important because it affects the retention of radionuclides by the disposal system. The waste form and EBS materials provide a barrier to release either directly (as in the case of waste forms in which the radionuclides are initially immobilized), or indirectly (as in the case of containment materials that restrict the ingress of groundwater or the egress of radionuclides that are released as the waste forms and EBS materials degrade). 1.1.1 Steps involved in making such predictions include problem definition, testing, modeling, and model confirmation. 1.1.2 The predictions are based on models derived from theoretical considerat...

American Society for Testing and Materials. Philadelphia

2007-01-01T23:59:59.000Z

300

Naturally fractured tight gas reservoir detection optimization  

SciTech Connect (OSTI)

The goal of the work this quarter has been to partition and high-grade the Greater Green River basin for exploration efforts in the Upper Cretaceous tight gas play and to initiate resource assessment of the basin. The work plan for the quarter of July 1-September 30, 1998 comprised three tasks: (1) Refining the exploration process for deep, naturally fractured gas reservoirs; (2) Partitioning of the basin based on structure and areas of overpressure; (3) Examination of the Kinney and Canyon Creek fields with respect to the Cretaceous tight gas play and initiation of the resource assessment of the Vermilion sub-basin partition (which contains these two fields); and (4) Initiation analysis of the Deep Green River Partition with respect to the Stratos well and assessment of the resource in the partition.

NONE

1998-11-30T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Optimization of fractured well performance of horizontal gas wells  

E-Print Network [OSTI]

................................................24 3.4 Ideal Number of Transverse Fractures..........................................26 3.5 Constant Volume Transverse Fractures ........................................32 3.6... of a longitudinal fracture..............................................10 2.5 Example of horizontal well with longitudinal fracture performance .............11 2.6 DVS representation of transverse fractures...

Magalhaes, Fellipe Vieira

2009-06-02T23:59:59.000Z

302

Fracture induced anisotropy in viscoelastic UNLP, 11 Octubre de 2012  

E-Print Network [OSTI]

Fracture induced anisotropy in viscoelastic media UNLP, 11 Octubre de 2012 . Fracture induced anisotropy in viscoelastic media ­ p. #12;Fractured media. I Fractures are common in the earth's crust due to different factors, for instance, tectonic stresses and natural or artificial hydraulic fracturing caused

Santos, Juan

303

Transitionaltensile fracture propagation: a status report T. Engelder  

E-Print Network [OSTI]

Abstract One model for the development of hybrid shear fractures is transitional±tensile fracture that is the hybrid of a joint and a shear fracture. Crack±seal veins with oblique ®bers are possible candidates of a spectrum of brittle fracture types, and that some fractures are a hybrid of both end members (cf. Hancock

Engelder, Terry

304

Development of a punching technique for ductile fracture testing over a wide range of stress states and strain rates  

E-Print Network [OSTI]

Advanced High Strength Steels (AHSS) are becoming increasingly popular in automotive design because of possible weight savings due to the high strength. However, traditional methods are not capable of predicting fracture ...

Walters, Carey Leroy

2009-01-01T23:59:59.000Z

305

Observations of the Release of Non-methane Hydrocarbons from Fractured Shale  

Science Journals Connector (OSTI)

The organic content of shale has become of commercial interest as a source of hydrocarbons, owing to the development of hydraulic fracturing (“fracking”). ... These findings suggest that other hydrocarbons of commercial interest may be extracted from shale and open the possibility to optimize the “fracking” process, improving gas yields and reducing environmental impacts. ... This technique, termed hydraulic fracturing (commonly known as “fracking”), consists of drilling a well in the prospective shale units and injecting water under high pressure mixed with sand (?5%) and chemical additives (?0.2%) to fracture the rock and stimulate the release of hydrocarbons. ...

Roberto Sommariva; Robert S. Blake; Robert J. Cuss; Rebecca L. Cordell; Jon F. Harrington; Iain R. White; Paul S. Monks

2014-06-30T23:59:59.000Z

306

Sizing of a hot dry rock reservoir from a hydraulic fracturing experiment  

SciTech Connect (OSTI)

Hot dry rock (HDR) reservoirs do not lend themselves to the standard methods of reservoir sizing developed in the petroleum industry such as the buildup/drawdown test. In a HDR reservoir the reservoir is created by the injection of fluid. This process of hydraulic fracturing of the reservoir rock usually involves injection of a large volume (5 million gallons) at high rates (40BPM). A methodology is presented for sizing the HDR reservoir created during the hydraulic fracturing process. The reservoir created during a recent fracturing experiment is sized using the techniques presented. This reservoir is then investigated for commercial potential by simulation of long term power production. 5 refs., 7 figs.

Zyvoloski, G.

1985-01-01T23:59:59.000Z

307

Hydraulic fracturing in tight, fissured media  

SciTech Connect (OSTI)

Large volumes of natural gas are found in tight, fissured reservoirs. Hydraulic fracturing can enhance recovery, but many complications, such as pressure-sensitive or accelerated leakoff, damage, and complex fracturing, arise during treatment of such reservoirs. This paper reports that special procedures generally should be considered during breakdown and fracturing of these reservoirs. In addition, the use of alternative stimulation strategies may be beneficial.

Warpinski, N.R. (Sandia National Lab., Albuquerque, NM (US))

1991-02-01T23:59:59.000Z

308

Investigation of the effect of gel residue on hydraulic fracture conductivity using dynamic fracture conductivity test  

E-Print Network [OSTI]

INVESTIGATION OF THE EFFECT OF GEL RESIDUE ON HYDRAULIC FRACTURE CONDUCTIVITY USING DYNAMIC FRACTURE CONDUCTIVITY TEST A Thesis by FIVMAN MARPAUNG Submitted to the Office of Graduate Studies of Texas A&M University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE December 2007 Major Subject: Petroleum Engineering INVESTIGATION OF THE EFFECT OF GEL RESIDUE ON HYDRAULIC FRACTURE CONDUCTIVITY USING DYNAMIC FRACTURE CONDUCTIVITY TEST A...

Marpaung, Fivman

2008-10-10T23:59:59.000Z

309

Effects of fracturing fluid recovery upon well performance and ultimate recovery of hydraulically fractured gas wells  

E-Print Network [OSTI]

EFFECTS OF FRACTURING FLUID RECOVERY UPON WELL PERFORMANCE AND ULTIMATE RECOVERY OF HYDRAULICALLY FRACTURED GAS WELLS A Thesis IAN MARIE BERTHELOT Submitted to the Office of Graduate Studies of Texas AdtM University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 1990 Major Subject: Petroleum Engineering EFFECTS OF FRACTURING FLUID RECOVERY UPON WELL PERFORMANCE AND ULTIMATE RECOVERY OF HYDRAULICALLY FRACTURED GAS WELLS by JAN MARIE BERTIIELOT Appmved...

Berthelot, Jan Marie

2012-06-07T23:59:59.000Z

310

Shale Gas Development Challenges: Fracture Fluids | Department...  

Office of Environmental Management (EM)

Fluids Shale Gas Development Challenges: Fracture Fluids More Documents & Publications Natural Gas from Shale: Questions and Answers Shale Gas Glossary FracFocus 2.0 Task Force...

311

Hydraulic fracturing and shale gas extraction.  

E-Print Network [OSTI]

??In the past decade the technique of horizontal drilling and hydraulic fracturing has been improved so much that it has become a cost effective method… (more)

Klein, Michael

2012-01-01T23:59:59.000Z

312

Geomechanical review of hydraulic fracturing technology .  

E-Print Network [OSTI]

??Hydraulic fracturing as a method for recovering unconventional shale gas has been around for several decades. Significant research and improvement in field methods have been… (more)

Arop, Julius Bankong

2013-01-01T23:59:59.000Z

313

Method of fracturing a geological formation  

DOE Patents [OSTI]

An improved method of fracturing a geological formation surrounding a well bore is disclosed. A relatively small explosive charge is emplaced in a well bore and the bore is subsequently hydraulically pressurized to a pressure less than the formation breakdown pressure and preferably greater than the fracture propagation pressure of the formation. The charge is denoted while the bore is so pressurized, resulting in the formation of multiple fractures in the surrounding formation with little or no accompanying formation damage. Subsequent hydraulic pressurization can be used to propagate and extend the fractures in a conventional manner. The method is useful for stimulating production of oil, gas and possibly water from suitable geologic formations.

Johnson, James O. (2679-B Walnut, Los Alamos, NM 87544)

1990-01-01T23:59:59.000Z

314

Fracture characteristics and their relationships to producing...  

Open Energy Info (EERE)

area Jump to: navigation, search OpenEI Reference LibraryAdd to library Book: Fracture characteristics and their relationships to producing zones in deep wells, Raft River...

315

Geothermal: Sponsored by OSTI -- Fracture Characterization in...  

Office of Scientific and Technical Information (OSTI)

Fracture Characterization in Enhanced Geothermal Systems by Wellbore and Reservoir Analysis Geothermal Technologies Legacy Collection HelpFAQ | Site Map | Contact Us | Admin Log...

316

Structural Settings Of Hydrothermal Outflow- Fracture Permeability...  

Open Energy Info (EERE)

Settings Of Hydrothermal Outflow- Fracture Permeability Maintained By Fault Propagation And Interaction Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal...

317

Seismic Fracture Characterization Methods for Enhanced Geothermal...  

Broader source: Energy.gov (indexed) [DOE]

5 4.5.2 Seismic Fracture Characterization Methods for Enhanced Geothermal Systems Presentation Number: 022 Investigator: Queen, John (Hi-Q Geophysical Inc.) Objectives: To develop...

318

Microearthquake Technology for EGS Fracture Characterization...  

Broader source: Energy.gov (indexed) [DOE]

1 4.5.1 Microearthquake Technology for EGS Fracture Characterization Presentation Number: 021 Investigator: Foulger, Gillian (Foulger Consulting) Objectives: To understand how EGS...

319

Naturally fractured tight gas reservoir detection optimization  

SciTech Connect (OSTI)

The work plan for the quarter of October 1, 1997--December 31, 1997 consisted of two tasks: (1) Present results of Rulison field test at various conferences, seminars, and to Barrett Resources and Snyder Oil Co. and (2) Continue work into developing a predictive quantitative method for locating fault-related natural fractures. The first task was completed during this reporting period. The second task continues the beginning of quantitative fracture mechanics analysis of the geologic processes that are involved for the development of fault-related natural fractures. The goal of this work is to develop a predictive capability of locating natural fractures prior to drilling.

NONE

1998-09-30T23:59:59.000Z

320

Results of a 1995 hydraulic fracturing survey and a comparison of 1995 and 1990 industry practices  

SciTech Connect (OSTI)

This paper presents the results of a hydraulic fracturing survey conducted in 1995 on behalf of the Gas Research institute (GRI). The purpose of the survey was to determine the types of formations that are normally fracture treated; gather data on the fracture treatments that are normally pumped; determine the level of data collection being conducted in the field; determine the level of data analysis being conducted in the office and the field; solicit opinions on the level of technology required to obtain an accurate analysis for fracture treatments; solicit opinions of the limitations of current technology; determine what costs operators could justify to analyze fracture treatment data and obtain ideas on new areas of research. Data gathered in the survey included respondents company size (major, large/small independent, service company or consultant), geographical area of operation, well depths and permeabilities, fracture treatment size, proppant type and volume, level of detail in data gathering, fracture treatment design and real-time analysis. The 1995 data were compared to a similar survey conducted in 1990 by GRI to determine technology trends.

Carter, R.H.; Holditch, S.A.; Wolhart, S.L.

1996-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

On the evaluation of Fast-SAGD process in naturally fractured heavy oil reservoir  

Science Journals Connector (OSTI)

Abstract Very recently, Fast-SAGD as a modification of steam assisted gravity drainage (SAGD) has been much attended due to lower cumulative steam oil ratio as well as higher cumulative oil production. However, there are still many suspicions about the successful application of this method in naturally fractured reservoirs (NFR) in which faults, fissures, vugs, micro-fractures, poorly interconnected matrix pore structure as well as undesirable wettability are combined with high-viscosity oil. In this communication, initially, Fast-SAGD has been compared with traditional SAGD in an Iranian naturally fractured heavy oil reservoir with oil wet rock using CMG-STARS thermal simulator. Moreover, the effects of operational parameters on Fast-SAGD method have been investigated. In addition, a novel economical model has been established in which all economical parameters including input cash flow costs such as the rate of oil production and oil price, and the output cash flow costs such as capital expenditures (CAPEX), operating expenditures (OPEX), injection material and pipe line tariffs, have been considered. During the optimization of the operational parameters, it was observed that by increasing steam injection rate into both offset and SAGD wells in Fast-SAGD system, ultimate recovery factor (RF) increased, but ultimate net present value (NPV) increased up to an optimal point which could be due to the increased SOR value. By increasing steam injection pressure into offset well, both the ultimate RF and NPV increased up to an optimal point. To optimally select parameters such as the number of cyclic steam stimulation (CSS) cycles, elevation of CSS well and well spacing of SAGD well pair, sensitivity analysis should be performed to achieve the best case economically and technically due to the lack of a decrease or increase trend. In contrast to conventional reservoirs, the performance affected by start-up time at the offset well during Fast-SAGD process in fractured reservoirs indicates that earlier start-up time of steam injection leads to high RF and NPV.

Arash Kamari; Abdolhossein Hemmati-Sarapardeh; Amir H. Mohammadi; Hani Hashemi-Kiasari; Erfan Mohagheghian

2015-01-01T23:59:59.000Z

322

Geometrical and transport properties of single fractures: influence of the roughness of the fracture  

E-Print Network [OSTI]

Geometrical and transport properties of single fractures: influence of the roughness of the fracture walls H. Auradou Univ Pierre et Marie Curie-Paris6, Univ Paris-Sud, CNRS, F-91405. Lab FAST, Bat reviews the main features of the transport properties of single fractures. A particular attention paid

Paris-Sud XI, Université de

323

Application of zircaloy deformation and fracture maps to predicting dry spent fuel storage conditions  

SciTech Connect (OSTI)

The research reported details the development of theoretical deformation and fracture maps for Zircaloy at temperatures between 50 and 850/sup 0/C and for stresses between 5 and 500 MPa. The maps predict behavior which is in agreement with a large number of experimental observations reported in the literature. Transformations in deformation and fracture mechanisms, creep rate magnitudes, and times to fracture are predicted from the maps. Results are reported for grain sizes of 5 ..mu..m. The deformation and fracture maps are altered for irradiation effects based upon high stress-high temperature, short time, postirradiation data. Maximum allowable temperature limits to achieve 40 years dry storage are calculated as a function of time spent in wet pool storage using a decaying cask temperature function and a life fraction rule. 122 references, 15 figures, 4 tables.

Chin, G.A.; Madsen, N.H.; Khan, M.A.

1983-08-01T23:59:59.000Z

324

Laboratory-scale fracture conductivity created by acid etching  

E-Print Network [OSTI]

Success of acid fracturing treatment depends greatly on the created conductivity under closure stress. In order to have sufficient conductivity, the fracture face must be non-uniformly etched while the fracture strength maintained to withstand...

Pournik, Maysam

2009-05-15T23:59:59.000Z

325

MULTIDIMENSIONAL NUMERICAL SIMULATION OF FLUID FLOW IN FRACTURED POROUS MEDIA  

E-Print Network [OSTI]

and fluid flow in the hydraulic fracturing process." Ph.D.depth by means of hydraulic fracturing." in Rock Mechanics:Fig. 13. Simulation of hydraulic fracturing: field data on

Narasimhan, T.N.

2014-01-01T23:59:59.000Z

326

A PKN Hydraulic Fracture Model Study and Formation Permeability Determination  

E-Print Network [OSTI]

Hydraulic fracturing is an important method used to enhance the recovery of oil and gas from reservoirs, especially for low permeability formations. The distribution of pressure in fractures and fracture geometry are needed to design conventional...

Xiang, Jing

2012-02-14T23:59:59.000Z

327

FINITE FRACTURE MECHANICS OF MATRIX MICROCRACKING IN COMPOSITES  

E-Print Network [OSTI]

FINITE FRACTURE MECHANICS OF MATRIX MICROCRACKING IN COMPOSITES JOHN A. NAIRN INTRODUCTION damage following complex loading conditions. This chapter describes a fracture mechanics approach to the microcracking problem. A complicating feature of composite fracture mechanics analysis is that laminates often

Nairn, John A.

328

Seismic characterization of fractured reservoirs using 3D double beams  

E-Print Network [OSTI]

We propose an efficient target-oriented method to characterize seismic properties of fractured reservoirs: the spacing between fractures and the fracture orientation. We use both singly scattered and multiply scattered ...

Zheng, Yingcai

2012-01-01T23:59:59.000Z

329

Fracture toughness evaluation for N Reactor pressure tubes of Zircaloy-2 using the electric-potential method  

SciTech Connect (OSTI)

Zircaloy is commonly used for the cladding or pressure tubes in commercial reactors because of its strength, corrosion resistance, and low absorption of thermal neutrons. Fracture toughness test techniques using small samples fabricated from archival materials from N Reactor pressure tubes of Zircaloy-2 were developed to study the factors affecting tube fracture toughness. Compact tension specimen thickness was limited by the wall thickness (7 mm) of the tubes. Specimens (5 mm thick) were prepared for fracture toughness testing and results were analyzed using the J-integral approach. To reduce the high cost of irradiated specimen testing and to more easily precrack specimens remotely, single-specimen potential drop techniques were employed to evaluate the fracture toughness of Zircaloy-2. The initiation fracture toughness was determined from J-R curves, which were constructed by plotting values of J as a function of crack extension computed from the electric-potential calibration curve. The J-R curves obtained from the calibration curve equation fit the blunting line region. The curves also fit heat-tint data well. The effects of neutron fluence and hydrogen content on the fracture toughness of N Reactor pressure tubes were evaluated. Neutron irradiation substantially degraded fracture toughness. Increasing fluence decreased the fracture toughness of the alloy. Hydrogen also decreased fracture toughness, but this effect was insignificant for the pressure tubes tested. 8 refs., 13 figs., 3 tabs.

Huang, F.H.

1991-11-01T23:59:59.000Z

330

Hydraulic fracture stimulation treatment of Well Baca 23. Geothermal Reservoir Well-Stimulation Program  

SciTech Connect (OSTI)

Well Stimulation Experiment No. 5 of the Geothermal Reservoir Well Stimulation Program (GRWSP) was performed on March 22, 1981 in Baca 23, located in Union's Redondo Creek Project Area in Sandoval County, New Mexico. The treatment selected was a large hydraulic fracture job designed specifically for, and utilizing frac materials chosen for, the high temperature geothermal environment. The well selection, fracture treatment, experiment evaluation, and summary of the job costs are presented herein.

Not Available

1981-06-01T23:59:59.000Z

331

Vertebral Compression Fracture (VCF) After Spine Stereotactic Body Radiation Therapy (SBRT): Analysis of Predictive Factors  

SciTech Connect (OSTI)

Purpose: Vertebral compression fractures (VCFs) are increasingly observed after spine stereotactic body radiation therapy (SBRT). The aim of this study was to determine the risk of VCF after spine SBRT and identify clinical and dosimetric factors predictive for VCF. The analysis incorporated the recently described Spinal Instability Neoplastic Score (SINS) criteria. Methods and Materials: The primary endpoint of this study was the development of a de novo VCF (ie, new endplate fracture or collapse deformity) or fracture progression based on an existing fracture at the site of treatment after SBRT. We retrospectively scored 167 spinal segments in 90 patients treated with spine SBRT according to each of the 6 SINS criteria. We also evaluated the presence of paraspinal extension, prior radiation, various dosimetric parameters including dose per fraction ({>=}20 Gy vs <20 Gy), age, and histology. Results: The median follow-up was 7.4 months. We identified 19 fractures (11%): 12 de novo fractures (63%) and 7 cases of fracture progression (37%). The mean time to fracture after SBRT was 3.3 months (range, 0.5-21.6 months). The 1-year fracture-free probability was 87.3%. Multivariate analysis confirmed that alignment (P=.0003), lytic lesions (P=.007), lung (P=.03) and hepatocellular (P<.0001) primary histologies, and dose per fraction of 20 Gy or greater (P=.004) were significant predictors of VCF. Conclusions: The presence of kyphotic/scoliotic deformity and the presence of lytic tumor were the only predictive factors of VCF based on the original 6 SINS criteria. We also report that patients with lung and hepatocellular tumors and treatment with SBRT of 20 Gy or greater in a single fraction are at a higher risk of VCF.

Cunha, Marcelo V.R. [Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada)] [Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Al-Omair, Ameen [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada)] [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Atenafu, Eshetu G. [Department of Biostatistics, University Health Network, University of Toronto, Toronto, Ontario (Canada)] [Department of Biostatistics, University Health Network, University of Toronto, Toronto, Ontario (Canada); Masucci, Giuseppina Laura; Letourneau, Daniel [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada)] [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Korol, Renee [Department of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada)] [Department of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Yu, Eugene [Department of Radiology and Otolaryngology-Head and Neck Surgery, University Health Network, Mount Sinai Hospital and Women's College Hospital, University of Toronto, Toronto, Ontario (Canada)] [Department of Radiology and Otolaryngology-Head and Neck Surgery, University Health Network, Mount Sinai Hospital and Women's College Hospital, University of Toronto, Toronto, Ontario (Canada); Howard, Peter [Department of Radiology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada)] [Department of Radiology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Lochray, Fiona [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada)] [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Costa, Leodante B. da [Department of Radiology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada)] [Department of Radiology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Fehlings, Michael G. [Division of Neurosurgery and Spinal Program, Toronto Western Hospital, University of Toronto, Toronto, Ontario (Canada)] [Division of Neurosurgery and Spinal Program, Toronto Western Hospital, University of Toronto, Toronto, Ontario (Canada); Sahgal, Arjun, E-mail: arjun.sahgal@sunnybrook.ca [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada) [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada)

2012-11-01T23:59:59.000Z

332

Laboratory data in support of hydraulically fracturing EGSP OH Well No. 3. Final report  

SciTech Connect (OSTI)

Geologic and geophysical interpretations of data from the EGSP OH Well No. 3 show that an organically lean shale has a gradual transition with depth to an organically rich shale and that two layers (bound each shale formation. The laboratory test program was designed to understand the containment and productivity of a hydraulic fracture induced in this well to enhance gas production from the shale. The porosity in the formations of interest, including the upper barrier, the lower barrier, and the organic shales, varied from 6 to 10 percent. The porosity of each formation averaged about 8%. Densities and ultrasonic velocities were used to evaluate dynamic moduli. Over the tested intervals moduli consistently increased with depth. This indicates the possibility of upward migration of an induced fracture. Perforations, therefore, should be limited to the lower portion of the pay sand and it is also advisable to use low injection rates. Of the four fracturing fluids tested, the two code-named Dow II and Hal I caused, respectively, the least amount of matrix permeability damage to the organically lean and organically rich shales. However, the damage caused by the other fracturing fluids were not severe enough to cause any significant permanent reduction in well productivity. The fracture conductivity tests under the influence of fracturing fluids indicated that Hal I and Dow I caused, respectively, the least amount of multilayered fracture conductivity damage to the organically lean and organically rich samples. For monolayer fracture conductivities Dow I caused least damage to the organically lean shale. With the exception of Dow III all other fluids showed good results in the monolayer tests for organically rich shales. In the situation where both the lean and the rich shales are to be fractured together, the use of either Hal I or Dow I is indicated.

Ahmed, U.; Swartz, G.C.; Scnatz, J.F.

1980-12-01T23:59:59.000Z

333

Rock-Fluid Chemistry Impacts on Shale Hydraulic Fracture and Microfracture Growth  

E-Print Network [OSTI]

fracturing fluids, to achieve improved fracture performance and higher recovery of natural gas from shale reservoirs....

Aderibigbe, Aderonke

2012-07-16T23:59:59.000Z

334

Coupled thermohydromechanical analysis of a heater test in unsaturated clay and fractured rock at Kamaishi Mine  

E-Print Network [OSTI]

injection and hydraulic fracturing stress measurements inlevel measured with hydraulic fracturing (reproduced from

Rutqvist, J.

2011-01-01T23:59:59.000Z

335

Modeling Single Well Injection-Withdrawal (SWIW) Tests for Characterization of Complex Fracture-Matrix Systems  

E-Print Network [OSTI]

exchange process. Hydraulic fracturing, or hydrofracking, ismore detail below. Hydraulic fracturing, or hydrofracking,

Cotte, F.P.

2012-01-01T23:59:59.000Z

336

E-Print Network 3.0 - apophyseal ring fracture Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

fracture Search Powered by Explorit Topic List Advanced Search Sample search results for: apophyseal ring fracture...

337

Aging and Fracture of Human Cortical Bone and Tooth Dentin  

E-Print Network [OSTI]

in both biological materials, resistance to fracture arisesof fracture resistance in these biological materials, asresistance path along these interfaces through the material.

Ager III, Joel W.

2008-01-01T23:59:59.000Z

338

Numerical Modeling of Hydraulic Fracturing in Oil Sands  

E-Print Network [OSTI]

Hydraulic fracturing is a widely used and e cient technique for enhancing oil ... for analyzing hydraulic fracturing in rocks, are in general not satisfactory for oil ...

2008-11-16T23:59:59.000Z

339

Finite element modeling of hydraulic fracturing in 3D  

E-Print Network [OSTI]

Mar 22, 2013 ... Two examples of hydraulic fracturing are given. when the pressure buildup ... Hydraulic fracturing is the coupled dynamics of frac- ture and ?uid ...

2013-03-22T23:59:59.000Z

340

Seismic Studies of a Massive Hydraulic Fracturing Experiment...  

Open Energy Info (EERE)

a Massive Hydraulic Fracturing Experiment Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Seismic Studies of a Massive Hydraulic Fracturing...

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Characterizing Fractures in the Geysers Geothermal Field by Micro...  

Broader source: Energy.gov (indexed) [DOE]

Efficient Use of MEQ Data Auto-picker Soft Computing Triggered vs induced seismicity. Fracture Mapping Fractal Dimensions Hot dry rock fracture regime Monitoring FluidTemp Dynamic...

342

The Role of Geochemistry and Stress on Fracture Development and...  

Broader source: Energy.gov (indexed) [DOE]

The Role of Geochemistry and Stress on Fracture Development and Proppant Behavior in EGS Reservoirs The Role of Geochemistry and Stress on Fracture Development and Proppant...

343

Tracer Methods for Characterizing Fracture Creation in Enhanced...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Tracer Methods for Characterizing Fracture Creation in Enhanced Geothermal Systems; 2010 Geothermal Technology Program Peer Review Report Tracer Methods for Characterizing Fracture...

344

Fracture Characterization in Enhanced Geothermal Systems by Wellbore...  

Broader source: Energy.gov (indexed) [DOE]

Fracture Characterization in Enhanced Geothermal Systems by Wellbore and Reservoir Analysis Fracture Characterization in Enhanced Geothermal Systems by Wellbore and Reservoir...

345

Fracture Network and Fluid Flow Imaging for EGS Applications...  

Broader source: Energy.gov (indexed) [DOE]

Fracture Network and Fluid Flow Imaging for EGS Applications from Multi-Dimensional Electrical Resistivity Structure Fracture Network and Fluid Flow Imaging for EGS Applications...

346

Imaging, Characterizing, and Modeling of Fracture Networks and...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS...

347

Irradiation Effects on Human Cortical Bone Fracture Behavior  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic...

348

Imaging, Characterizing, and Modeling of Fracture Networks and...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs Lianjie Huang Los Alamos National Lab Seismicity and Reservoir Fracture Characterization...

349

Fracture Characterization in Enhanced Geothermal Systems by Wellbore...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Fracture Characterization in Enhanced Geothermal Systems by Wellbore and Reservoir Analysis; 2010 Geothermal Technology Program Peer Review Report Fracture Characterization in...

350

Three-dimensional Modeling of Fracture Clusters in Geothermal...  

Broader source: Energy.gov (indexed) [DOE]

Three-dimensional Modeling of Fracture Clusters in Geothermal Reservoirs; 2010 Geothermal Technology Program Peer Review Report Three-dimensional Modeling of Fracture Clusters in...

351

Joint inversion of electrical and seismic data for Fracture char...  

Broader source: Energy.gov (indexed) [DOE]

Joint inversion of electrical and seismic data for Fracture char. and Imaging of Fluid Flow in Geothermal Systems Joint inversion of electrical and seismic data for Fracture char....

352

Fracture Evolution Following a Hydraulic Stimulation within an...  

Broader source: Energy.gov (indexed) [DOE]

Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir DOE Geothermal Peer Review...

353

Displacement and segment linkage in fracture zones  

SciTech Connect (OSTI)

Fault zones and vein arrays are composed of overstepping and linked segments, so knowledge of segment evolution is crucial in understanding the development of zones. Displacement-distance profiles of faults and veins are used to study the development of segments and zones. Detailed mapping of normal and strike-slip faults allows comparison of the displacement-distance characteristics of faults both normal and parallel to the displacement vector, i.e. modes III and II propagation respectively. Similarly, vein width variations can be used to study mode I propagation. Displacement varies with distance along fractures, with zero displacement at fracture tips. Steep displacement gradients can occur where faults and extension fractures overstep because of displacement transfer between the segments. This displacement transfer is accommodated by relay and bridge structures. Overstepping fractures may link to form a single fracture with an irregular displacement-distance profile. A linkage point is often marked by a bend with a displacement minimum, where relay/bridge structures are preserved as normal drag. Displacement variations are also caused by fault bends, conjugate relationships and by lithological variations. As interaction between fractures increases, r/d[sub MAX] ratios tend to decrease (where r = the distance between the tip and the point of maximum displacement, and d[sub MAX] = maximum displacement). As a result of the interaction of fracture segments, fracture zones tend to have complex displacement-distance profiles.

Peacock, D.C.P.; Sanderson, D.J. (Univ. of Southampton (United Kingdom). Dept. of Geology)

1992-01-01T23:59:59.000Z

354

Accounting for Remaining Injected Fracturing Fluid  

E-Print Network [OSTI]

The technology of multi-stage fracturing of horizontal wells made the development of shale gas reservoirs become greatly successful during the past decades. A large amount of fracturing fluid, usually from 53,000 bbls to 81,400 bbls, is injected...

Zhang, Yannan

2013-12-06T23:59:59.000Z

355

Harmonic experiments to model fracture induced anisotropy  

E-Print Network [OSTI]

´oleo (IGPUBA), Universidad de Buenos Aires, Argentina, and Universidad Nacional de La Plata, Argentina. work;Fractured media. III · Displacement discontinuities conserve energy, while velocity discontinuities generate energy loss at the fractures. The specific viscosity accounts for the presence of a liquid under

Santos, Juan

356

Harmonic experiments to model fracture induced anisotropy  

E-Print Network [OSTI]

´oleo (IGPUBA), Universidad de Buenos Aires, Argentina, and Universidad Nacional de La Plata, Argentina. work;Fractured media. III Displacement discontinuities conserve energy, while velocity discontinuities generate energy loss at the fractures. The specific viscosity accounts for the presence of a liquid under

Santos, Juan

357

A synergistic approach to optimizing hydraulic fracturing  

SciTech Connect (OSTI)

Combining measurement, simulation, and imaging technologies into an integrated program can help operators achieve the best hydraulic fracture treatment possible. Hydrocarbon production can be significantly increased when fractures are extended to the planned length, and fracturing fluid is retained within the zone of interest. Fractures that break out of zone increase the risk of excess water production with the hydrocarbon. Consequently, the ability to select suitable operational parameters for hydraulic fracturing is critical to job success. An evaluation of formation properties and potential barriers to hydraulic fracturing can be made with three-dimensional (3D) simulation to integrate data taken from wireline logs, waveform sonic logs, and microfrac measurements. In-situ stress orientation is determined by use of a downhole extensometer, oriented cores, anelastic strain recovery (ASR) measurements, and borehole imaging logs. Sidewall cores can be taken perpendicular to wellbore walls without distorting the borehole or the core taken; orientation of the cores can be determined with imaging logs run after coring. Natural fractures can be viewed with a downhole video camera lowered into the well on fiberoptic cable. Effectiveness of fracture treatments may be evaluated with various gamma ray logging techniques production logs comparing expected production to actual zonal contribution. Refined procedures that result from after-frac analysis can be used to plain field development for optimal reservoir drainage.

Kessler, C.; Venditto, J.; McMechan, D.; Edwards, P.

1994-12-31T23:59:59.000Z

358

Fracture mechanics of cellular glass  

SciTech Connect (OSTI)

Cellular glasses are prime candidate materials for the structural substrate of mirrored glass for solar concentrator reflecting panels. These materials are brittle, however, and susceptible to mechanical failure from slow crack growth caused by a stress corrosion mechanism. The results are detailed of one part of a program established to develop improved cellular glasses and to characterize the behavior of these and commercially available materials. Commercial and developmental cellular glasses were tested and analyzed using standard testing techniques and models developed from linear fracture mechanics. Two models describing the fracture behavior of these materials are developed. Slow crack growth behavior in cellular glass was found to be more complex than that encountered in dense glasses or ceramics. The crack velocity was found to be strongly dependent upon water vapor transport to the tip of the moving crack. The existence of a static fatigue limit was not conclusively established, however, it is speculated that slow crack growth behavior in Region I may be slower, by orders of magnitude, than that found in dense glasses.

Zwissler, J.G.; Adams, M.A.

1981-02-01T23:59:59.000Z

359

Hydraulic Fracturing Technology | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Oil & Gas » Shale Gas » Hydraulic Oil & Gas » Shale Gas » Hydraulic Fracturing Technology Hydraulic Fracturing Technology Image taken from "Shale Gas: Applying Technology to Solve America's Energy Challenges," NETL, 2011. Image taken from "Shale Gas: Applying Technology to Solve America's Energy Challenges," NETL, 2011. Hydraulic fracturing is a technique in which large volumes of water and sand, and small volumes of chemical additives are injected into low-permeability subsurface formations to increase oil or natural gas flow. The injection pressure of the pumped fluid creates fractures that enhance gas and fluid flow, and the sand or other coarse material holds the fractures open. Most of the injected fluid flows back to the wellbore and is pumped to the surface.

360

Hydraulic fracturing slurry transport in horizontal pipes  

SciTech Connect (OSTI)

Horizontal-well activity has increased throughout the industry in the past few years. To design a successful hydraulic fracturing treatment for horizontal wells, accurate information on the transport properties of slurry in horizontal pipe is required. Limited information exists that can be used to estimate critical deposition and resuspension velocities when proppants are transported in horizontal wells with non-Newtonian fracturing gels. This paper presents a study of transport properties of various hydraulic fracturing slurries in horizontal pipes. Flow data are gathered in three transparent horizontal pipes with different diameters. Linear and crosslinked fracturing gels were studied, and the effects of variables--e.g., pipe size; polymer-gelling-agent concentration; fluid rheological properties; crosslinking effects; proppant size, density, and concentrations; fluid density; and slurry pump rate--on critical deposition and resuspension velocities were investigated. Also, equations to estimate the critical deposition and resuspension velocities of fracturing gels are provided.

Shah, S.N.; Lord, D.L. (Halliburton Services (US))

1990-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Effects of high pressure-dependent leakoff and high process-zone stress in coal-stimulation treatments  

SciTech Connect (OSTI)

Hydraulic fracturing in coals has been studied extensively over the last two decades; however, there are factors that were often ignored or incorrectly diagnosed, resulting in screenouts. Assuming that a majority of the perforations are open and there are no problems with the stimulation fluids, screenouts during coal hydraulic-fracture treatments can be attributed to either high pressure-dependent leakoff (PDL), high process-zone stress (PZS) or in some cases both. The objective of this work is to discuss, help identify, and present solutions to address these reservoir-related issues such that screenouts can be avoided in optimized refracture treatments and new well stimulations. The tools for identifying these reservoir-related parameters include a diagnostic fracture-injection test (DFIT) and a grid-oriented fully functional 3D fracture simulator with shear decoupling. An example for each respective case is presented in this paper. In the first example, in which high PZS was considered to be the dominant reason for screenout or pressure out, the well was restimulated successfully by implementing the solutions presented in this paper. In the second example, in which high PDL was considered to be the main reason for screenout, there were several wells in the same project area that exhibited the same behavior resulting in screenouts. After implementing the solutions presented in this paper to address high PDL, all new wells were stimulated successfully without any issues.

Ramurthy, M.; Lyons, B.; Hendrickson, R.B.; Barree, R.D.; Magill, D.R. [Halliburton, Denver, CO (United States)

2009-08-15T23:59:59.000Z

362

Fully coupled fluid flow and geomechanics in the study of hydraulic fracturing and post-fracture production.  

E-Print Network [OSTI]

??This work addresses the poroelastic effect on the processes involved in hydraulic fracturing and post-fracture production using a finite element based fully coupled poroelastic model… (more)

Aghighi, Mohammad Ali

2007-01-01T23:59:59.000Z

363

Parallel, Multigrid Finite Element Simulator for Fractured/Faulted and Other Complex Reservoirs based on Common Component Architecture (CCA)  

SciTech Connect (OSTI)

Black-oil, compositional and thermal simulators have been developed to address different physical processes in reservoir simulation. A number of different types of discretization methods have also been proposed to address issues related to representing the complex reservoir geometry. These methods are more significant for fractured reservoirs where the geometry can be particularly challenging. In this project, a general modular framework for reservoir simulation was developed, wherein the physical models were efficiently decoupled from the discretization methods. This made it possible to couple any discretization method with different physical models. Oil characterization methods are becoming increasingly sophisticated, and it is possible to construct geologically constrained models of faulted/fractured reservoirs. Discrete Fracture Network (DFN) simulation provides the option of performing multiphase calculations on spatially explicit, geologically feasible fracture sets. Multiphase DFN simulations of and sensitivity studies on a wide variety of fracture networks created using fracture creation/simulation programs was undertaken in the first part of this project. This involved creating interfaces to seamlessly convert the fracture characterization information into simulator input, grid the complex geometry, perform the simulations, and analyze and visualize results. Benchmarking and comparison with conventional simulators was also a component of this work. After demonstration of the fact that multiphase simulations can be carried out on complex fracture networks, quantitative effects of the heterogeneity of fracture properties were evaluated. Reservoirs are populated with fractures of several different scales and properties. A multiscale fracture modeling study was undertaken and the effects of heterogeneity and storage on water displacement dynamics in fractured basements were investigated. In gravity-dominated systems, more oil could be recovered at a given pore volume of injection at lower rates. However, if oil production can be continued at high water cuts, the discounted cumulative production usually favors higher production rates. The workflow developed during the project was also used to perform multiphase simulations in heterogeneous, fracture-matrix systems. Compositional and thermal-compositional simulators were developed for fractured reservoirs using the generalized framework. The thermal-compositional simulator was based on a novel 'equation-alignment' approach that helped choose the correct variables to solve depending on the number of phases present and the prescribed component partitioning. The simulators were used in steamflooding and in insitu combustion applications. The framework was constructed to be inherently parallel. The partitioning routines employed in the framework allowed generalized partitioning on highly complex fractured reservoirs and in instances when wells (incorporated in these models as line sources) were divided between two or more processors.

Milind Deo; Chung-Kan Huang; Huabing Wang

2008-08-31T23:59:59.000Z

364

Fracture-resistant lanthanide scintillators  

DOE Patents [OSTI]

Lanthanide halide alloys have recently enabled scintillating gamma ray spectrometers comparable to room temperature semiconductors (<3% FWHM energy resolutions at 662 keV). However brittle fracture of these materials upon cooling hinders the growth of large volume crystals. Efforts to improve the strength through non-lanthanide alloy substitution, while preserving scintillation, have been demonstrated. Isovalent alloys having nominal compositions of comprising Al, Ga, Sc, Y, and In dopants as well as aliovalent alloys comprising Ca, Sr, Zr, Hf, Zn, and Pb dopants were prepared. All of these alloys exhibit bright fluorescence under UV excitation, with varying shifts in the spectral peaks and intensities relative to pure CeBr.sub.3. Further, these alloys scintillate when coupled to a photomultiplier tube (PMT) and exposed to .sup.137Cs gamma rays.

Doty, F. Patrick (Livermore, CA)

2011-01-04T23:59:59.000Z

365

Characterizing hydraulically fractured reservoirs using induced microearthquakes  

SciTech Connect (OSTI)

Hydraulic fracturing is a common method employed to increase the production of oil and gas fields. Recently, there has been increased interest in monitoring the microearthquakes induced by hydraulic fracturing as a means of obtaining data to characterize reservoir changeS induced by the injection. Two types of microearthquakes have been observed during hydraulic fracturing. Tensile events have been observed and modeled as the parting of the surfaces of a fracture. A majority of the events observed have been shear-slip events, where two sides of a fault plane slip parallel to each other but in opposite directions. The locations of the microearthquakes can be analyzed to determine regions where significant seismic energy was released, which presumably are regions where injected fluid penetrated into the rock along pre-existing fractures or zones of weakness. The spatial patterns in the locations can be analyzed to fine regions where events cluster along planes, which are interpreted to be the dominant fluid flow paths. Imaging methods can also be applied to the travel time and waveform data to obtain direct evidence for the locations of the fractures or fracture zones. 27 refs., 2 figs.

Fehler, M.

1991-01-01T23:59:59.000Z

366

Sponsorship includes: Agriculture in the  

E-Print Network [OSTI]

Sponsorship includes: · Agriculture in the Classroom · Douglas County Farm Bureau · Gifford Farm · University of Nebraska Agricultural Research and Development Center · University of Nebraska- Lincoln Awareness Coalition is to help youth, primarily from urban communities, become aware of agriculture

Nebraska-Lincoln, University of

367

OPTIMIZATION OF INFILL DRILLING IN NATURALLY-FRACTURED TIGHT-GAS RESERVOIRS  

SciTech Connect (OSTI)

A major goal of industry and the U.S. Department of Energy (DOE) fossil energy program is to increase gas reserves in tight-gas reservoirs. Infill drilling and hydraulic fracture stimulation in these reservoirs are important reservoir management strategies to increase production and reserves. Phase II of this DOE/cooperative industry project focused on optimization of infill drilling and evaluation of hydraulic fracturing in naturally-fractured tight-gas reservoirs. The cooperative project involved multidisciplinary reservoir characterization and simulation studies to determine infill well potential in the Mesaverde and Dakota sandstone formations at selected areas in the San Juan Basin of northwestern New Mexico. This work used the methodology and approach developed in Phase I. Integrated reservoir description and hydraulic fracture treatment analyses were also conducted in the Pecos Slope Abo tight-gas reservoir in southeastern New Mexico and the Lewis Shale in the San Juan Basin. This study has demonstrated a methodology to (1) describe reservoir heterogeneities and natural fracture systems, (2) determine reservoir permeability and permeability anisotropy, (3) define the elliptical drainage area and recoverable gas for existing wells, (4) determine the optimal location and number of new in-fill wells to maximize economic recovery, (5) forecast the increase in total cumulative gas production from infill drilling, and (6) evaluate hydraulic fracture simulation treatments and their impact on well drainage area and infill well potential. Industry partners during the course of this five-year project included BP, Burlington Resources, ConocoPhillips, and Williams.

Lawrence W. Teufel; Her-Yuan Chen; Thomas W. Engler; Bruce Hart

2004-05-01T23:59:59.000Z

368

Fractured gas reservoirs in the Devonian shale of the Illinois and Appalachian basins  

SciTech Connect (OSTI)

The Devonian and Lower Mississippian black shale sequence of Kentucky includes the New Albany Shale of Illinois basin and the Ohio Shale of the Appalachian basin. Fractured reservoirs in the Ohio Shale contain a major gas resource, but have not been so prolific in the New Albany Shale. The authors propose two models of fractured shale reservoirs in both the Illinois and the Appalachian basins, to be tested with gas production data. (1) Where reactivated basement faults have propagated to the surface, the lack of an effective seal has prevented the development of overpressure. The resulting fracture system is entirely tectonic is origin, and served mainly as a conduit for gas migration from the basin to the surface. Gas accumulations in such reservoirs typically are small and underpressured. (2) Where basement faults have been reactivated but have not reached the surface, a seal on the fractured reservoir is preserved. In areas where thermal maturity has been adequate, overpressuring due to gas generation resulted in a major extension of the fracture system, as well as enhanced gas compression and adsorption. Such gas accumulations are relatively large. Original overpressuring has been largely lost, due both to natural depletion and to uncontrolled production. The relative thermal immaturity of the Illinois basin accounts for the scarcity of the second type of fractured reservoir and the small magnitude of the New Albany Shale gas resource.

Hamilton-Smith, T.; Walker, D.; Nuttall, B. (Kentucky Geological Survey, Lexington (United States))

1991-08-01T23:59:59.000Z

369

Is there an increased risk of hip fracture in multiple sclerosis? Analysis of the Nationwide Inpatient Sample  

E-Print Network [OSTI]

Impaired ambulation, frequent falls, and prolonged immobilization combined with the high rate of vitamin D deficiency in people with multiple sclerosis (MS) could lead to an increased risk of hip fracture....

Bhattacharya, Rajib K.; Vaishnav, Niralee; Dubinsky, Richard M.

2014-02-13T23:59:59.000Z

370

Evaluation of fracture risk and potential drug holidays for postmenopausal women on long-term bisphosphonate therapy  

E-Print Network [OSTI]

Study objective: To describe characteristics of postmenopausal women on long-term bisphosphonate therapy who fall into one of four fracture risk categories (low, mild, moderate, high), and to determine the prevalence of women eligible for a drug...

Kostoff, Matthew D.; Saseen, Joseph J.; Borgelt, Laura M.

2014-04-28T23:59:59.000Z

371

Estimating the fracture density of small-scale vertical fractures when large-scale vertical fractures are present  

E-Print Network [OSTI]

When fractures are vertical, aligned and their dimensions are small relative to the seismic wavelength, the medium can be considered to be an equivalent Horizontal Transverse Isotropic (HTI) medium. However, geophysical ...

Liu, Yuwei

2013-01-01T23:59:59.000Z

372

Reply to Davies: Hydraulic fracturing remains a possible mechanism for  

E-Print Network [OSTI]

LETTER Reply to Davies: Hydraulic fracturing remains a possible mechanism for observed methane mechanisms were leaky gas well casings and the possibility that hydraulic fracturing might generate new- knowledged the possibility of hydraulic fracturing playing a role. Is it possible that hydraulic fracturing

Jackson, Robert B.

373

Coupling schemes for modeling hydraulic fracture propagation using the XFEM  

E-Print Network [OSTI]

Coupling schemes for modeling hydraulic fracture propagation using the XFEM Elizaveta Gordeliy of hydraulic fractures in an elastic medium. With appropriate enrichment, the XFEM resolves the Neumann(h) accuracy. For hydraulic fracture problems with a lag separating the uid front from the fracture front, we

Peirce, Anthony

374

Calibration of hydraulic and tracer tests in fractured media  

E-Print Network [OSTI]

Calibration of hydraulic and tracer tests in fractured media represented by a DFN Model L. D. Donado, X. Sanchez-Vila, E. Ruiz* & F. J. Elorza** * Enviros Spain S.L. ** UPM #12;Fractured Media Water flows through fractures (matrix basically impervious ­ though relevant to transport) Fractures at all

Politècnica de Catalunya, Universitat

375

Envelope of Fracture Density Dragana Todorovic-Marinic*  

E-Print Network [OSTI]

Envelope of Fracture Density Dragana Todorovic-Marinic* Veritas DGC Ltd., Calgary, Alberta, Canada that interpretation of fractures can be improved by using the envelope of the fracture density. It has been shown that open, fluid (or gas) filled fractures can be identified through the use of the AVAZ method (Gray et. al

Santos, Juan

376

Use of Tracers to Characterize Fractures in Engineered Geothermal Systems  

Broader source: Energy.gov [DOE]

Project Objectives: Measure interwell fracture surface area and fracture spacing using sorbing tracers; measure fracture surface areas adjacent to a single geothermal well using tracers and injection/backflow techniques; design, fabricate and test a downhole instrument for measuring fracture flow following a hydraulic stimulation experiment.

377

Physical model of a fractured reservoir | Open Energy Information  

Open Energy Info (EERE)

model of a fractured reservoir model of a fractured reservoir Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Physical model of a fractured reservoir Details Activities (1) Areas (1) Regions (0) Abstract: The objectives of the physical modeling effort are to: (1) evaluate injection-backflow testing for fractured reservoirs under conditions of known reservoir parameters (porosity, fracture width, etc.); (2) study the mechanisms controlling solute transport in fracture systems; and (3) provide data for validation of numerical models that explicitly simulate solute migration in fracture systems. The fracture network is 0.57-m wide, 1.7-m long, and consists of two sets of fractures at right angles to one another with a fracture spacing of 10.2 cm. A series of

378

Characterization and fluid flow simulation of naturally fractured Frontier sandstone, Green River Basin, Wyoming  

SciTech Connect (OSTI)

Significant gas reserves are present in low-permeability sandstones of the Frontier Formation in the greater Green River Basin, Wyoming. Successful exploitation of these reservoirs requires an understanding of the characteristics and fluid-flow response of the regional natural fracture system that controls reservoir productivity. Fracture characteristics were obtained from outcrop studies of Frontier sandstones at locations in the basin. The fracture data were combined with matrix permeability data to compute an anisotropic horizontal permeability tensor (magnitude and direction) corresponding to an equivalent reservoir system in the subsurface using a computational model developed by Oda (1985). This analysis shows that the maximum and minimum horizontal permeability and flow capacity are controlled by fracture intensity and decrease with increasing bed thickness. However, storage capacity is controlled by matrix porosity and increases linearly with increasing bed thickness. The relationship between bed thickness and the calculated fluid-flow properties was used in a reservoir simulation study of vertical, hydraulically-fractured and horizontal wells and horizontal wells of different lengths in analogous naturally fractured gas reservoirs. The simulation results show that flow capacity dominates early time production, while storage capacity dominates pressure support over time for vertical wells. For horizontal wells drilled perpendicular to the maximum permeability direction a high target production rate can be maintained over a longer time and have higher cumulative production than vertical wells. Longer horizontal wells are required for the same cumulative production with decreasing bed thickness.

Harstad, H. [New Mexico Tech, Socorro, NM (United States); Teufel, L.W.; Lorenz, J.C.; Brown, S.R. [Sandia National Labs., Albuquerque, NM (United States). Geomechanics Dept.

1996-08-01T23:59:59.000Z

379

Continuous time random walk analysis of solute transport in fractured porous media  

SciTech Connect (OSTI)

The objective of this work is to discuss solute transport phenomena in fractured porous media, where the macroscopic transport of contaminants in the highly permeable interconnected fractures can be strongly affected by solute exchange with the porous rock matrix. We are interested in a wide range of rock types, with matrix hydraulic conductivities varying from almost impermeable (e.g., granites) to somewhat permeable (e.g., porous sandstones). In the first case, molecular diffusion is the only transport process causing the transfer of contaminants between the fractures and the matrix blocks. In the second case, additional solute transfer occurs as a result of a combination of advective and dispersive transport mechanisms, with considerable impact on the macroscopic transport behavior. We start our study by conducting numerical tracer experiments employing a discrete (microscopic) representation of fractures and matrix. Using the discrete simulations as a surrogate for the 'correct' transport behavior, we then evaluate the accuracy of macroscopic (continuum) approaches in comparison with the discrete results. However, instead of using dual-continuum models, which are quite often used to account for this type of heterogeneity, we develop a macroscopic model based on the Continuous Time Random Walk (CTRW) framework, which characterizes the interaction between the fractured and porous rock domains by using a probability distribution function of residence times. A parametric study of how CTRW parameters evolve is presented, describing transport as a function of the hydraulic conductivity ratio between fractured and porous domains.

Cortis, Andrea; Cortis, Andrea; Birkholzer, Jens

2008-06-01T23:59:59.000Z

380

Fracture-enhanced porosity and permeability trends in Bakken Formation, Williston basin, western North Dakota  

SciTech Connect (OSTI)

Fractures play a critical role in oil production from the Bakken Formation (Devonian and Mississippian) in the North Dakota portion of the Williston basin. The Bakken Formation in the study area is known for its low matrix porosity and permeability, high organic content, thermal maturity, and relative lateral homogeneity. Core analysis has shown the effective porosity and permeability development within the Bakken Formation to be related primarily to fracturing. In theory, lineaments mapped on the surface reflect the geometry of basement blocks and the zones of fracturing propagated upward from them. Fracturing in the Williston basin is thought to have occurred along reactivated basement-block boundaries in response to varying tectonic stresses and crustal flexure throughout the Phanerozoic. Landsat-derived lineament maps were examined for the area between 47/degrees/ and 48/degrees/ north lat. and 103/degrees/ and 104/degrees/ west long. (northern Billings and Golden Valley Counties, and western McKenzie County, North Dakota) in an attempt to identify large-scale fracture trends. In the absence of major tectonic deformation in the craton, a subtle pattern of fracturing has propagated upward through the sedimentary cover and emerged as linear topographic features visible on these large-scale, remote-sensed images.

Freisatz, W.B.

1988-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Influence of fracture scale heterogeneity on the flow properties of three-dimensional discrete fracture networks (DFN)  

E-Print Network [OSTI]

Influence of fracture scale heterogeneity on the flow properties of three-dimensional discrete fracture networks (DFN) J.-R. de Dreuzy,1,2 Y. Méheust,2 and G. Pichot3 Received 18 May 2012; revised 28 of fractured media has been so far studied independently at the fracture- and network- scales, we propose

Paris-Sud XI, Université de

382

Using the fracture energies for the two films a first estimate of fracture toughness, K, can be found.  

E-Print Network [OSTI]

· Using the fracture energies for the two films a first estimate of fracture toughness, K, can be found. · Assumptions are made to estimate the crack area based on the fracture mode seen in the SEM. · The total crack length is assumed to be 3 times the contact radius, , at the fracture depth. · To find

Collins, Gary S.

383

A Fracture-Mechanics-Based Approach to Fracture Control in Biomedical Devices Manufactured From Superelastic Nitinol Tube  

E-Print Network [OSTI]

A Fracture-Mechanics-Based Approach to Fracture Control in Biomedical Devices Manufactured From: 10.1002/jbm.b.30840 Abstract: Several key fracture-mechanics parameters associated with the onset of subcritical and critical cracking, specifically the fracture toughness, crack-resistance curve, and fatigue

Ritchie, Robert

384

An Advanced Fracture Characterization and Well Path Navigation System for Effective Re-Development and Enhancement of Ultimate Recovery from the Complex Monterey Reservoir of South Ellwood Field, Offshore California  

SciTech Connect (OSTI)

Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to over 10,000,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intended to investigate, map and characterize field fracture patterns and the reservoir conduit system. In the first phase of the project, state of the art borehole imaging technologies including FMI, dipole sonic, interference tests and production logs were employed to characterize fractures and micro faults. These data along with the existing database were used in the construction of a new geologic model of the fracture network. An innovative fracture network reservoir simulator was developed to better understand and manage the aquifer’s role in pressure maintenance and water production. In the second phase of this project, simulation models were used to plan the redevelopment of the field using high angle wells. Correct placement of the wells is critical to intersect the best-developed fracture zones and to avoid producing large volumes of water from the water leg. Particula r attention was paid to those areas of the field that have not been adequately developed with the existing producers. In cooperation with the DOE and the PTTC, the new data and the new fracture simulation model were shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the methodologies developed in this project. This report presents a summary of all technical work conducted during Budget Periods I and II. Venoco elected to terminate the project after Budget Period II and not to proceed with the activities planned for Budget Period III.

Horner, Steve; Ershaghi, Iraj

2006-06-30T23:59:59.000Z

385

3-D description of fracture surfaces and stress-sensitivity analysis for naturally fractured reservoirs  

SciTech Connect (OSTI)

Three kinds of reservoir cores (limestone, sandstone, and shale with natural fractures) were used to study the effect of morphology of fracture surfaces on stress sensitivity. The cores, obtained from the reservoirs with depths of 2170 to 2300 m, have fractures which are mated on a large scale, but unmated on a fine scale. A specially designed photoelectric scanner with a computer was used to describe the topography of the fracture surfaces. Then, theoretical analysis of the fracture closure was carried out based on the fracture topography generated. The scanning results show that the asperity has almost normal distributions for all three types of samples. For the tested samples, the fracture closure predicted by the elastic-contact theory is different from the laboratory measurements because plastic deformation of the aspirates plays an important role under the testing range of normal stresses. In this work, the traditionally used elastic-contact theory has been modified to better predict the stress sensitivity of reservoir fractures. Analysis shows that the standard deviation of the probability density function of asperity distribution has a great effect on the fracture closure rate.

Zhang, S.Q.; Jioa, D.; Meng, Y.F.; Fan, Y.

1997-08-01T23:59:59.000Z

386

Infiltration and Seepage Through Fractured Welded Tuff  

SciTech Connect (OSTI)

The Nopal I mine in Pena Blanca, Chihuahua, Mexico, contains a uranium ore deposit within fractured tuff. Previous mining activities exposed a level ground surface 8 m above an excavated mining adit. In this paper, we report results of ongoing research to understand and model percolation through the fractured tuff and seepage into a mined adit both of which are important processes for the performance of the proposed nuclear waste repository at Yucca Mountain. Travel of water plumes was modeled using one-dimensional numerical and analytical approaches. Most of the hydrologic properly estimates were calculated from mean fracture apertures and fracture density. Based on the modeling results, we presented constraints for the arrival time and temporal pattern of seepage at the adit.

T.A. Ghezzehei; P.F. Dobson; J.A. Rodriguez; P.J. Cook

2006-06-20T23:59:59.000Z

387

Hydraulic fracturing accelerates coalbed methane recovery  

SciTech Connect (OSTI)

Methane production from deep coal seams that never will be mined requires hydraulic fracturing for faster, optimal recovery. Since this can be a complex process, proper formation evaluation beforehand is essential, according to this paper.

Holditch, S.A. (Texas A and M Univ. (US)); Ely, J.W.; Semmelbeck, M.E.; Carter, R.H. (S.A. Holditch and Associates (US)); Hinkel, J.J.; Jeffrey, R.G. Jr. (Dowell Schlumberger (US))

1990-11-01T23:59:59.000Z

388

Multiphase flow in fractured porous media  

SciTech Connect (OSTI)

The major goal of this research project was to improve the understanding of the gas-oil two-phase flow in fractured porous media. In addition, miscible displacement was studied to evaluate its promise for enhanced recovery.

Firoozabadi, A.

1995-02-01T23:59:59.000Z

389

Universal asymptotic umbrella for hydraulic fracture modeling  

E-Print Network [OSTI]

The paper presents universal asymptotic solution needed for efficient modeling of hydraulic fractures. We show that when neglecting the lag, there is universal asymptotic equation for the near-front opening. It appears that apart from the mechanical properties of fluid and rock, the asymptotic opening depends merely on the local speed of fracture propagation. This implies that, on one hand, the global problem is ill-posed, when trying to solve it as a boundary value problem under a fixed position of the front. On the other hand, when properly used, the universal asymptotics drastically facilitates solving hydraulic fracture problems (both analytically and numerically). We derive simple universal asymptotics and comment on their employment for efficient numerical simulation of hydraulic fractures, in particular, by well-established Level Set and Fast Marching Methods.

Linkov, Aleksandr M

2014-01-01T23:59:59.000Z

390

Hydraulic fractur ing--also called hy  

E-Print Network [OSTI]

Hydraulic fractur ing--also called hy drofracking or frack ing--is a process where large volumes) is an aquatic invasive spe cies listed on the USDA's federal noxious weeds list (http:// www.aphis.usda.gov/plant_health

Goodman, Robert M.

391

Environmental challenges in fracturing of unconventional resources  

Science Journals Connector (OSTI)

...Fracturing and the environment. This talk showed...environmental risks and impacts associated with gas...time protecting the environment and safeguarding...Duncan, P. , 2011, Fracking and the environment: The contribution...

Azra N. Tutuncu; Chris Krohn; Stephan Gelinsky; Jacques Leveille; Cengiz Esmersoy; Ali I. Mese

392

Dynamic Fracture Toughness of Polymer Composites  

E-Print Network [OSTI]

that of defense or transport. In this project, the focus is on determining dynamic fracture toughness property of fiber reinforced polymer composites by using a combined numerical- experimental methodology. Impact tests are conducted on Split-Hopkinson pressure...

Harmeet Kaur

2012-02-14T23:59:59.000Z

393

Gas condensate damage in hydraulically fractured wells  

E-Print Network [OSTI]

), md 0.15 Porosity (g102), fraction 0.1 Water Saturation (S w ), fraction 0.16 Initial Pressure (p i ), psi 3,900 Injection Pressure (p inj ), psi 3,910 Dewpoint Pressure (p d ), psi 3,500 Temperature (T), o F 200 Total Compressibility (c g... simulation ..........................13 3.4 Permeability reduction normal to fracture face .........................................14 3.5 Quarter model for 80 acre drainage area....................................................15 3.6 Fracture face...

Adeyeye, Adedeji Ayoola

2004-09-30T23:59:59.000Z

394

Appendix F Cultural Resources, Including  

Broader source: Energy.gov (indexed) [DOE]

Appendix F Appendix F Cultural Resources, Including Section 106 Consultation STATE OF CALIFORNIA - THE RESOURCES AGENCY EDMUND G. BROWN, JR., Governor OFFICE OF HISTORIC PRESERVATION DEPARTMENT OF PARKS AND RECREATION 1725 23 rd Street, Suite 100 SACRAMENTO, CA 95816-7100 (916) 445-7000 Fax: (916) 445-7053 calshpo@parks.ca.gov www.ohp.parks.ca.gov June 14, 2011 Reply in Reference To: DOE110407A Angela Colamaria Loan Programs Office Environmental Compliance Division Department of Energy 1000 Independence Ave SW, LP-10 Washington, DC 20585 Re: Topaz Solar Farm, San Luis Obispo County, California Dear Ms. Colamaria: Thank you for seeking my consultation regarding the above noted undertaking. Pursuant to 36 CFR Part 800 (as amended 8-05-04) regulations implementing Section

395

Countries Gasoline Prices Including Taxes  

Gasoline and Diesel Fuel Update (EIA)

Countries (U.S. dollars per gallon, including taxes) Countries (U.S. dollars per gallon, including taxes) Date Belgium France Germany Italy Netherlands UK US 01/13/14 7.83 7.76 7.90 8.91 8.76 8.11 3.68 01/06/14 8.00 7.78 7.94 8.92 8.74 8.09 3.69 12/30/13 NA NA NA NA NA NA 3.68 12/23/13 NA NA NA NA NA NA 3.63 12/16/13 7.86 7.79 8.05 9.00 8.78 8.08 3.61 12/9/13 7.95 7.81 8.14 8.99 8.80 8.12 3.63 12/2/13 7.91 7.68 8.07 8.85 8.68 8.08 3.64 11/25/13 7.69 7.61 8.07 8.77 8.63 7.97 3.65 11/18/13 7.99 7.54 8.00 8.70 8.57 7.92 3.57 11/11/13 7.63 7.44 7.79 8.63 8.46 7.85 3.55 11/4/13 7.70 7.51 7.98 8.70 8.59 7.86 3.61 10/28/13 8.02 7.74 8.08 8.96 8.79 8.04 3.64 10/21/13 7.91 7.71 8.11 8.94 8.80 8.05 3.70 10/14/13 7.88 7.62 8.05 8.87 8.74 7.97 3.69

396

Well testing model for multi-fractured horizontal well for shale gas reservoirs with consideration of dual diffusion in matrix  

Science Journals Connector (OSTI)

Abstract Shale gas reservoir is typical unconventional reservoir, it's necessary to take advantage of multi-stage fractured horizontal well so as to develop those kinds of reservoirs, which can form high conductivity hydraulic fractures and activate natural fractures. Due to the existence of concentration gap between matrix and fractures, desorption gas can simultaneously diffuse into the natural fractures and hydraulic fractures. This process can be called dual diffusion. Based on the triple-porosity cubic model, this paper establishes a new well testing model of multi-stage fractured horizontal well in shale gas reservoir with consideration of the unique mechanisms of desorption and dual diffusion in matrix. Laplace transformation is employed to solve this new model. The pseudo pressure transient responses are inverted into real time space with stehfest numerical inversion algorithm. Type curves are plotted, and different flow regimes in shale gas reservoirs are identified and the effects of relevant parameters are analyzed as well. Considering the mechanism of dual diffusion in matrix, the flow can be divided into five regimes: early linear flow; pseudo-steady state inter-porosity flow; the diffusion from matrix into micro-fractures; the diffusion from matrix into hydraulic fractures and boundary-dominated flow. There are large distinctions of pressure response between pseudo steady state diffusion and unsteady state diffusion under different value of pore volume ratio. It's similar to the feature of pseudo-steady state inter-porosity flow, diffusion coefficient and Langmuir parameters reflect the characters of pseudo-steady state diffusion. The numbers of stage of hydraulic fractures have certain impact on the shape factor of matrix and the inter-porosity coefficient. This new model is validated compared with some existing models. Finally, coupled with an application, this mew model can be approximately reliable and make some more precise productivity prediction.

Leng Tian; Cong Xiao; Mingjin Liu; Daihong Gu; Guangyu Song; Helong Cao; Xianglong Li

2014-01-01T23:59:59.000Z

397

INNOVATAIVE METHODOLOGY FOR DETECTION OF FRACTURE-CONTROLLED SWEET SPOTS IN THE NORTHERN APPALACHIAN BASIN  

SciTech Connect (OSTI)

In the structure task, for this reporting period, the authors also edited and revised the map that displays the modified rose diagrams for the data they collected and reduced along the east side of Seneca Lake. They also revised the N-S transect that displays the frequency of ENE-striking fractures, and constructed a new N-S transect that shows the frequency of E-striking fractures. This transect compliments the earlier transect they constructed for fracture frequency of ENE-striking fractures. Significantly, the fracture frequency transect for E-W fractures shows a spike in fracture frequency in the region of the E-striking Firtree anticline that is observed on seismic reflection sections. The ENE fracture set does not exhibit an unusually high fracture frequency in this area. In contrast, the fracture frequency of the ENE-striking set is anomalously high in the region of the Trenton/Black River grabens. They have nearly completed reducing the data they collected from a NNW-SSE transect on the west side of Cayuga Lake and they have constructed modified rose diagrams for most sites. Structure contour maps and isopach maps have been revised based on additional well log analyses. Except for the Glodes Corners Field, the well spacing generally remains insufficient to identify faults or their precise locations. However, relatively sharp elevational changes east of Keuka Lake support the contention that faults occur along the east side of Keuka Lake. Similarly, a single well east of Seneca Lake shows that the Trenton there is low compared to distant wells, based on an assumed regional slope. This same area is where one of the Trenton grabens occurs. They have completed the interpretation of the reprocessed data that Quest licensed and had reprocessed. Several grabens observed in the Trenton and Black River reflectors are consistent with surface structure, soil gas, and aeromagnetic anomalies. In this report they display all four interpreted seismic lines. These data indicate that integration of aeromagnetic and topographic lineaments, surface structure, soil gas with seismic and well logs allows them to extrapolate Trenton-Black River trends away from confirmatory seismic lines.

Robert Jacobi; John Fountain

2002-06-30T23:59:59.000Z

398

A STATISTICAL FRACTURE MECHANICS APPROACH TO THE STRENGTH OF BRITTLE ROCK  

E-Print Network [OSTI]

Carlsson, H. , "Hydraulic fracturing and overcoring stress1949). Haimson, B.C. , "Hydraulic fracturing in porous andc.B. , "Laboratory hydraulic fracturing experiments in

Ratigan, J.L.

2010-01-01T23:59:59.000Z

399

Pressure analysis of the hydromechanical fracture behaviour in stimulated tight sedimentary geothermal reservoirs  

E-Print Network [OSTI]

Zimmermann, G. , 2005. Hydraulic fracturing in a sedimentaryare described in the hydraulic fracturing context, in whichoverview. However, hydraulic fracturing theories and related

Wessling, S.

2009-01-01T23:59:59.000Z

400

HYDRAULIC FRACTURING AND OVERCORING STRESS MEASUREMENTS IN A DEEP BOREHOLE AT THE STRIPA TEST MINE, SWEDEN  

E-Print Network [OSTI]

u l y 2 , 1 9 8 1 HYDRAULIC FRACTURING AND OVERCORING STRESSI nun LBL-12478 HYDRAULIC FRACTURING AND OVERCORING STRESSthe calculated stress. n HYDRAULIC FRACTURING EQUIPMENT AND

Doe, T.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Skull fracture vs. accessory sutures: how can we tell the difference?  

E-Print Network [OSTI]

fissure: diagnosis of fracture versus anatomic variants.be performed to identify fractures in suspected child abuse?skull: the diagnosis of fracture. Am J Roentgenol Radium

Sanchez, Thomas; Stewart, Deborah; Walvick, Matthew; Swischuk, Leonard

2010-01-01T23:59:59.000Z

402

Estimation of fracture flow parameters through numerical analysis of hydromechanical pressure pulses  

E-Print Network [OSTI]

from previous evaluations of fracture hydromechanicalof flow through fractures in rock, In: Proceedings ofsaturated, variable-aperture fracture, Geophys. Res. Lett. ,

Cappa, F.

2009-01-01T23:59:59.000Z

403

Acoustic Emission in a Fluid Saturated Hetergeneous Porous Layer with Application to Hydraulic Fracture  

E-Print Network [OSTI]

New Model of Hydraulic Fracture With an Induced Low Velocityand L. R. Meyer, 1988. Fracture Detectin Using P- Wave andof a Vertical Hydraulic Fracture, Earth Sciences Division,

Nelson, J.T.

2009-01-01T23:59:59.000Z

404

E-Print Network 3.0 - adjacent compression fractures Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and triangular columns formed by column-bounding fractures adjacent to inflation-fracture walls... the cooling rate, caus- ing increased fracturing ... Source: Kattenhorn,...

405

Effect of non-linear loading paths on sheet metal fracture : large strain in-plane compression followed by uniaxial tension  

E-Print Network [OSTI]

Advanced high strength steel sheets are rapidly entering the transport industry, as their high strength to weight ratio helps improving fuel and costs efficiency. The early ductile fracture of these materials limits their ...

Marcadet, Stephane (Stephane Jean Marie)

2012-01-01T23:59:59.000Z

406

Stochastic Modeling of a Fracture Network in a Hydraulically Fractured Shale-Gas Reservoir  

E-Print Network [OSTI]

of the hydraulic fracture patterns created during the well stimulation process. This work introduces a novel approach to model the hydraulic fractures in a shale reservoir using a stochastic method called random-walk. We see this approach as a beginning step...

Mhiri, Adnene

2014-08-10T23:59:59.000Z

407

Sealed glass coating of high temperature ceramic superconductors  

DOE Patents [OSTI]

A method and article of manufacture of a lead oxide based glass coating on a high temperature superconductor. The method includes preparing a dispersion of glass powders in a solution, applying the dispersion to the superconductor, drying the dispersion before applying another coating and heating the glass powder dispersion at temperatures below oxygen diffusion onset and above the glass melting point to form a continuous glass coating on the superconductor to establish compressive stresses which enhance the fracture strength of the superconductor.

Wu, Weite (Tainan, TW); Chu, Cha Y. (Garnerville, NY); Goretta, Kenneth C. (Downers Grove, IL); Routbort, Jules L. (Darien, IL)

1995-01-01T23:59:59.000Z

408

The influence of fracture properties on ground-water flow at the Bunker Hill Mine, Kellogg, Idaho  

SciTech Connect (OSTI)

The Bunker Hill Mine in northern Idaho is a large underground lead-zinc mine located in Precambrian metaquartzite rocks with virtually no primary porosity. Ground-water flow through these types of rocks is largely dependent upon the properties of fractures such as joints, faults and relict bedding planes. Ground water that flows into the mine via the fractures is contaminated by heavy metals and by the production of acid water, which results in a severe acid mine drainage problem. A more complete understanding of how the fractures influence the ground-water flow system is a prerequisite to the evaluation of reclamation alternatives to reduce acid drainage from the mine. Fracture mapping techniques were used to obtain detailed information on the fracture properties observed in the New East Reed drift of the Bunker Hill Mine. The data obtained include: (a) fracture type, (b) orientation, (c) trace length, (d) the number of visible terminations, (e) roughness (small-scale asperities), (f) waviness (larger-scale undulations), (g) infilling material, and (h) a qualitative measure of the amount of water flowing through each fracture.

Lachmar, T.E. [Utah State Univ., Logan, UT (United States). Dept. of Geology

1993-12-01T23:59:59.000Z

409

Fracture analysis of HFIR beam tube caused by radiation embrittlement  

SciTech Connect (OSTI)

With an attempt to estimate the neutron beam tube embrittlement condition for the Oak Ridge High Flux Isotope Reactor (HFIR), fracture mechanics calculations are carried out in this paper. The analysis provides some numerical result on how the tube has been structurally weakened. In this calculation, a lateral impact force is assumed. Numerical result is obtained on how much the critical crack size should be reduced if the beam tube has been subjected to an extended period of irradiation. It is also calculated that buckling strength of the tube is increased, not decreased, with irradiation.

Chang, S.J. [Oak Ridge National Lab., TN (United States). Research Reactors Div.

1994-12-31T23:59:59.000Z

410

Discussion of comparison study of hydraulic fracturing models -- Test case: GRI Staged Field Experiment No. 3  

SciTech Connect (OSTI)

This paper provides comments to a companion journal paper on predictive modeling of hydraulic fracturing patterns (N.R. Warpinski et. al., 1994). The former paper was designed to compare various modeling methods to demonstrate the most accurate methods under various geologic constraints. The comments of this paper are centered around potential deficiencies in the former authors paper which include: limited actual comparisons offered between models, the issues of matching predictive data with that from related field operations was lacking or undocumented, and the relevance/impact of accurate modeling on the overall hydraulic fracturing cost and production.

Cleary, M.P.

1994-02-01T23:59:59.000Z

411

Microbial Community Changes in Hydraulic Fracturing Fluids and Produced Water from Shale Gas Extraction  

SciTech Connect (OSTI)

Microbial communities associated with produced water from hydraulic fracturing are not well understood, and their deleterious activity can lead to significant increases in production costs and adverse environmental impacts. In this study, we compared the microbial ecology in prefracturing fluids (fracturing source water and fracturing fluid) and produced water at multiple time points from a natural gas well in southwestern Pennsylvania using 16S rRNA gene-based clone libraries, pyrosequencing, and quantitative PCR. The majority of the bacterial community in prefracturing fluids constituted aerobic species affiliated with the class Alphaproteobacteria. However, their relative abundance decreased in produced water with an increase in halotolerant, anaerobic/facultative anaerobic species affiliated with the classes Clostridia, Bacilli, Gammaproteobacteria, Epsilonproteobacteria, Bacteroidia, and Fusobacteria. Produced water collected at the last time point (day 187) consisted almost entirely of sequences similar to Clostridia and showed a decrease in bacterial abundance by 3 orders of magnitude compared to the prefracturing fluids and produced water samplesfrom earlier time points. Geochemical analysis showed that produced water contained higher concentrations of salts and total radioactivity compared to prefracturing fluids. This study provides evidence of long-term subsurface selection of the microbial community introduced through hydraulic fracturing, which may include significant implications for disinfection as well as reuse of produced water in future fracturing operations.

Mohan, Arvind Murali; Hartsock, Angela; Bibby, Kyle J.; Hammack, Richard W.; Vidic, Radisav D.; Gregory, Kelvin B.

2013-11-19T23:59:59.000Z

412

Reference flaw size for structural and fracture analysis of Types 1 and 2 waste tanks  

SciTech Connect (OSTI)

High Level Waste Engineering (HLWE) is reviewing the Technical Standard requirements for tank level and minimum wall temperature. These requirements are necessary to minimize the probability of brittle fracture of the primary liner due to normal operating and/or seismic loads. The review includes the determination of a reference flaw size, a maximum through-wall crack length, which may reasonably be applied to structural and fracture analysis of the Type I and II waste tank primary liners. This memorandum briefly discusses the mechanism of crack initiation and propagation, the inspections of primary wall cracks, and a statistical analysis of the measured crack lengths. Recommendations on additional analyses which may increase the confidence in the reference flaw size will also be presented. The primary liner for Type I and II waste tanks is fabricated from ASTM A285, Grade B carbon steel (A285). The liner received no heat treatments to relieve residual stresses in the heat affected zones. Five Type I waste tanks and all four Type II waste tanks developed through-wall cracks. Leaks developed in tanks 9, 10,14 and 16 within less than two years. Small surface cracks were also observed on the interior of the tank primary. The cracks were perpendicular to the butt welds and extended through the heat affected zone before stopping shortly after penetrating the base metal. The largest leakage of radioactive waste, approximately 185,000 gallons from the primary into the annulus, occurred from Tank 16, a Type II waste tank. During inspections of this tank over 300 leaks were discovered with the longest observed crack being approximately 6 inches. Due to the large number of observed cracks and the amount of leakage, this wag the only tank that was surveyed for crack lengths. For this analysis, Tank 16 will be considered representative of all Type I and II waste tanks because the materials, construction practices, and tank chemistry represented a worst case.

Wiersma, B.J.; Sindelar, R.L.

1994-01-01T23:59:59.000Z

413

Fracture Characterization Technologies | Open Energy Information  

Open Energy Info (EERE)

Fracture Characterization Technologies Fracture Characterization Technologies Jump to: navigation, search Geothermal ARRA Funded Projects for Fracture Characterization Technologies Loading map... {"format":"googlemaps3","type":"ROADMAP","types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"limit":200,"offset":0,"link":"all","sort":[""],"order":[],"headers":"show","mainlabel":"","intro":"","outro":"","searchlabel":"\u2026 further results","default":"","geoservice":"google","zoom":false,"width":"600px","height":"350px","centre":false,"layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","icon":"","visitedicon":"","forceshow":true,"showtitle":true,"hidenamespace":false,"template":false,"title":"","label":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"locations":[{"text":"

414

Mechanisms and impact of damage resulting from hydraulic fracturing. Topical report, May 1995-July 1996  

SciTech Connect (OSTI)

This topical report documents the mechanisms of formation damage following hydraulic fracturing and their impact upon gas well productivity. The categories of damage reviewed include absolute or matrix permeability damage, relative permeability alterations, the damage of natural fracture permeability mechanisms and proppant conductivity impairment. Case studies are reviewed in which attempts are made to mitigate each of the damage types. Industry surveys have been conducted to determine the perceptions of the industry on the topic of formation damage following hydraulic fracturing and to identify key formations in which formation damage is a problem. From this information, technical hurdles and new technology needs are identified and estimates are made of the benefits of developing and applying minimum formation damage technology.

Penny, G.S.; Conway, M.W.; Almond, S.W.; Himes, R.; Nick, K.E.

1996-08-01T23:59:59.000Z

415

Effects of subsurface fracture interactions on surface deformation  

E-Print Network [OSTI]

Although the surface deformation resulting from the opening of a single fracture in a layered elastic half-space resembles the observed deformation at the InSalah site, it seems unlikely that only a single fracture is ...

Jerry, Ruel (Ruel Valentine)

2013-01-01T23:59:59.000Z

416

Effective fracture geometry obtained with large water sand ratio  

E-Print Network [OSTI]

Shale gas formation exhibits some unusual reservoir characteristics: nano-darcy matrix permeability, presence of natural fractures and gas storage on the matrix surface that makes it unique in many ways. It’s difficult to design an optimum fracture...

Kumar, Amrendra

2009-05-15T23:59:59.000Z

417

Experimental Study of Acid Fracture Conductivity of Austin Chalk Formation  

E-Print Network [OSTI]

Acid fracture conductivity and the effect of key variables in the etching process during acid fracturing can be assessed at the laboratory scale. This is accomplished by using an experimental apparatus that simulates acid injection fluxes comparable...

Nino Penaloza, Andrea

2013-05-01T23:59:59.000Z

418

Development and testing of an advanced acid fracture conductivity apparatus  

E-Print Network [OSTI]

wells. Acid fracturing is a standard practice to increase the production rate and to improve ultimate recovery in carbonate reservoirs. There have been successful cases in most carbonate reservoirs around the world. However acid fracture performance...

Zou, ChunLei

2006-08-16T23:59:59.000Z

419

How can we use one fracture to locate another?  

E-Print Network [OSTI]

Hydraulic fracturing is an important tool that helps extract fluids from the subsurface. It is critical in applications ranging from enhanced oil recovery to geothermal energy pro-duction. As the goal of fracturing is to ...

Poliannikov, Oleg V.

2011-01-01T23:59:59.000Z

420

Effectiveness of microseismic monitoring for optimizing hydraulic fracturing in California  

E-Print Network [OSTI]

Hydraulic fracturing has fundamentally changed the oil and gas industry in the past 10 years. Bakersfield, California provides a unique case study because steam injection, a type of hydraulic fracturing, has been used there ...

Alampi, Ann M

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

On equivalence of thinning fluids used for hydraulic fracturing  

E-Print Network [OSTI]

The paper aims to answer the question: if and how non-Newtonian fluids may be compared in their mechanical action when used for hydraulic fracturing? By employing the modified formulation of the PKN problem we obtain its simple analytical solutions in the cases of perfectly plastic and Newtonian fluids. Since the results for shear thinning fluids are intermediate between those for these cases, the obtained equation for the fracture length suggests a criterion of the equivalence of various shear thinning fluids for the problem of hydraulic fractures. We assume fluids equivalent in their hydrofracturing action, when at a reference time they produce fractures of the same length. The equation for the fracture length translates the equivalence in terms of the hydraulic fracture length and treatment time into the equivalence in terms of the properties of a fracturing fluid (behavior and consistency indices). Analysis shows that the influence of the consistency and behavior indices on the fracture length, particle v...

Linkov, Alexander

2012-01-01T23:59:59.000Z

422

Hydraulic Fracture Monitoring: A Jonah Field Case Study  

E-Print Network [OSTI]

Hydraulic fracturing involves the injection of a fluid to fracture oil and gas reservoirs, and thus increase their permeability. The process creates numerous microseismic events, which can be used to monitor subsurface ...

Seher, T.

2011-01-01T23:59:59.000Z

423

Seismic characterization of fractured reservoirs by focusing Gaussian beams  

E-Print Network [OSTI]

Naturally fractured reservoirs occur worldwide, and they account for the bulk of global oil production. The most important impact of fractures is their influence on fluid flow. To maximize oil production, the characterization ...

Zheng, Yingcai

424

A Bayesian framework for fracture characterization from surface seismic data  

E-Print Network [OSTI]

We describe a methodology for quantitatively characterizing the fractured nature of a hydrocarbon or geothermal reservoir from surface seismic data under a Bayesian inference framework. Fractures provide pathways for fluid ...

Zamanian, S. Ahmad

2012-01-01T23:59:59.000Z

425

Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir  

Broader source: Energy.gov [DOE]

DOE Geothermal Peer Review 2010 - Presentation. This project will provide the first ever formal evaluation of fracture and fracture flow evolution in an EGS reservoir following a hydraulic stimulation.

426

Fracture Characterization from Scattered Energy: A Case Study  

E-Print Network [OSTI]

We use 3D surface seismic data to determine the presence and the preferred orientation of fracture corridors in a field. The Scattering Index method is proving to be a robust tool for detecting and mapping fracture corridors. ...

Grandi, Samantha K.

2006-01-01T23:59:59.000Z

427

Incorporating Rigorous Height Determination into Unified Fracture Design  

E-Print Network [OSTI]

; height, length and width. Unified fracture design (UFD) offers a method to determine the fracture dimensions providing the maximum productivity index for a specific proppant amount. Then, in order to achieve the maximum productivity index, the treatment...

Pitakbunkate, Termpan

2010-10-12T23:59:59.000Z

428

Finite Difference Modeling of Seismic Responses to Intersecting Fracture Sets  

E-Print Network [OSTI]

Fractured reservoir characterization is becoming increasingly important for the petroleum industry. Currentmethods for this task are developed based on effectivemedia theory, which assumes the cracks or fractures in a ...

Chi, Shihong

2006-01-01T23:59:59.000Z

429

Compartmentalization analysis using discrete fracture network models  

SciTech Connect (OSTI)

This paper illustrates how Discrete Fracture Network (DFN) technology can serve as a basis for the calculation of reservoir engineering parameters for the development of fractured reservoirs. It describes the development of quantitative techniques for defining the geometry and volume of structurally controlled compartments. These techniques are based on a combination of stochastic geometry, computational geometry, and graph theory. The parameters addressed are compartment size, matrix block size and tributary drainage volume. The concept of DFN models is explained and methodologies to compute these parameters are demonstrated.

La Pointe, P.R.; Eiben, T.; Dershowitz, W. [Golder Associates Inc., Redmond, WA (United States); Wadleigh, E. [Marathon Oil Company, Midland, TX (United States). Mid-Continent Region Production

1997-12-31T23:59:59.000Z

430

Compartmentalization analysis using discrete fracture network models  

SciTech Connect (OSTI)

This paper illustrates how Discrete Fracture Network (DFN) technology can serve as a basis for the calculation of reservoir engineering parameters for the development of fractured reservoirs. It describes the development of quantitative techniques for defining the geometry and volume of structurally controlled compartments. These techniques are based on a combination of stochastic geometry, computational geometry, and graph the theory. The parameters addressed are compartment size, matrix block size and tributary drainage volume. The concept of DFN models is explained and methodologies to compute these parameters are demonstrated.

La Pointe, P.R.; Eiben, T.; Dershowitz, W. [Golder Associates, Redmond, VA (United States); Wadleigh, E. [Marathon Oil Co., Midland, TX (United States)

1997-08-01T23:59:59.000Z

431

Application of a 3D hydraulic-fracturing simulator for design of acid-fracturing treatments  

SciTech Connect (OSTI)

Field experience during 1989--90 shows that application of a 3D hydraulic-fracturing simulator increases success of acid-fracturing well treatments. Fracture extension can be limited to the oil-bearing pay, maximum lateral extension can be realized within the height constraint, and acid/rock contact time can be increased by a factor of between 3 and 30. Oil-production response can be improved over other stimulation designs while water-production response can be limited. These methods have been applied in mature waterfloods of the Permian Basin and Cedar Creek anticline.

Morgenthaler, L.N. (Shell Development Co., Houston, TX (United States))

1994-02-01T23:59:59.000Z

432

The application of local approach to assess the influence of in-plane constraint on cleavage fracture  

SciTech Connect (OSTI)

The assessment of real or postulated flaws within critical components is conventionally carried out using methods based on single parameter fracture mechanics. For low constraint configurations (e.g. shallow cracks) such methods can provide highly conservative assessments. Two-parameter (J-T, J-Q) fracture mechanics has been developed to quantify the influence of crack-tip constraint on fracture and this development has been incorporated into a modified R6 framework to reduce the conservatisms associated with the assessment of low constraint configurations. This framework requires that the constraint of the structure is quantified (with respect to T or Q) and that the materials fracture response to constraint is measured by testing a number of cracked specimens which sample a range of constraint levels. An alternative method of assessment, which may be used in situations where fracture data are unavailable over the full range of constraint, is the so-called local approach to fracture. In this Paper, the local approach has been used alongside the modified R6 framework to assess the cleavage fracture behavior of a well characterized mild steel plate at {minus}50 C. The local approach method predicts: (i) an upswing in cleavage fracture toughness as a function of decreasing crack-tip constraint which is conservative with respect to the actual materials response, (ii) an increase in the scatter of cleavage fracture toughness as a function of decreasing crack-tip constraint. This is a direct consequence of framing the local approach model within two-parameter Weibull statistics. Finally it is shown that the local approach may be used successfully alongside the modified R6 framework to assess low constraint geometries: resultant failure assessment curves reduce the conservatism of the conventional Option 1 curve.

Sherry, A.H.; Sanderson, D.J.; Lidbury, D.P.G. [AEA Technology, Risley (United Kingdom); Ainsworth, R.A. [Nuclear Electric, Berkeley (United Kingdom); Kikuchi, K. [JAERI, Tokai, Ibaraki (Japan)

1995-11-01T23:59:59.000Z

433

INVESTIGATION OF EFFICIENCY IMPROVEMENTS DURING CO2 INJECTION IN HYDRAULICALLY AND NATURALLY FRACTURED RESERVOIRS  

SciTech Connect (OSTI)

The objective of this project is to perform unique laboratory experiments with artificial fractured cores (AFCs) and X-ray CT to examine the physical mechanisms of bypassing in HFR and NFR that eventually result in more efficient CO{sub 2} flooding in heterogeneous or fracture-dominated reservoirs. To achieve this objective, we divided the report into two chapters. The first chapter was to image and perform experimental investigation of transfer mechanisms during CO{sub 2} flooding in NFR and HFR using X-ray CT scanner. In this chapter, we emphasized our work on understanding the connection between fracture properties and fundamentals of transfer mechanism from matrix to fractures and fluid flow through fracture systems. We started our work by investigating the effect of different overburden pressures and stress-state conditions on rock properties and fluid flow. Since the fracture aperture is one of important parameter that governs the fluid flow through the fracture systems, the average fracture aperture from the fluid flow experiments and fracture aperture distribution derived from X-ray CT scan were estimated for our modeling purposes. The fracture properties and fluid flow have significant changes in response to different overburden pressures and stress-state conditions. The fracture aperture distribution follows lognormal distribution even at elevated stress conditions. Later, we also investigated the fluid transfers between matrix and fracture that control imbibition process. We evaluated dimensionless time for validating the scheme of upscaling laboratory experiments to field dimensions. In CO{sub 2} injection experiments, the use of X-ray CT has allowed us to understand the mechanisms of CO{sub 2} flooding process in fractured system and to take important steps in reducing oil bypassed. When CO{sub 2} flooding experiments were performed on a short core with a fracture at the center of the core, the gravity plays an important role in the recovery of oil even in a short matrix block. This results are contrary with the previous believes that gravity drainage has always been associated with tall matrix blocks. In order to reduce oil bypassed, we injected water that has been viscosified with a polymer into the fracture to divert CO{sub 2} flow into matrix and delay CO{sub 2} breakthrough. Although the breakthrough time reduced considerably, water ''leak off'' into the matrix was very high. A cross-linked gel was used in the fracture to avoid this problem. The gel was found to overcome ''leak off'' problems and effectively divert CO{sub 2} flow into the matrix. As part of our technology transfer activity, we investigated the natural fracture aperture distribution of Tensleep formation cores. We found that the measured apertures distributions follow log normal distribution as expected. The second chapter deals with analysis and modeling the laboratory experiments and fluid flow through fractured networks. We derived a new equation to determine the average fracture aperture and the amount of each flow through fracture and matrix system. The results of this study were used as the observed data and for validating the simulation model. The idea behind this study is to validate the use of a set of smooth parallel plates that is common in modeling fracture system. The results suggest that fracture apertures need to be distributed to accurately model the experimental results. In order to study the imbibition process in details, we developed imbibition simulator. We validated our model with X-ray CT experimental data from different imbibition experiments. We found that the proper simulation model requires matching both weight gain and CT water saturation simultaneously as oppose to common practices in matching imbibition process with weight gain only because of lack information from CT scan. The work was continued by developing dual porosity simulation using empirical transfer function (ETF) derived from imbibition experiments. This allows reduction of uncertainty parameter in modeling transfer of fluids from matrix to the fra

David S. Schechter

2005-09-28T23:59:59.000Z

434

Experimental and Analytical Research on Fracture Processes in ROck  

SciTech Connect (OSTI)

Experimental studies on fracture propagation and coalescence were conducted which together with previous tests by this group on gypsum and marble, provide information on fracturing. Specifically, different fracture geometries wsere tested, which together with the different material properties will provide the basis for analytical/numerical modeling. INitial steps on the models were made as were initial investigations on the effect of pressurized water on fracture coalescence.

Herbert H.. Einstein; Jay Miller; Bruno Silva

2009-02-27T23:59:59.000Z

435

Analysis of Thermally Induced Changes in Fractured Rock Permeability during Eight Years of Heating and Cooling at the Yucca Mountain Drift Scale Test  

SciTech Connect (OSTI)

We analyzed a data set of thermally induced changes in fractured rock permeability during a four-year heating (up to 200 C) and subsequent four-year cooling of a large volume, partially saturated and highly fractured volcanic tuff at the Yucca Mountain Drift Scale Test, in Nevada, USA. Permeability estimates were derived from about 700 pneumatic (air-injection) tests, taken periodically at 44 packed-off borehole intervals during the heating and cooling cycle from November 1997 through November 2005. We analyzed air-permeability data by numerical modeling of thermally induced stress and moisture movements and their impact on air permeability within the highly fractured rock. Our analysis shows that changes in air permeability during the initial four-year heating period, which were limited to about one order of magnitude, were caused by the combined effects of thermal-mechanically-induced stress on fracture aperture and thermal-hydrologically-induced changes in fracture moisture content. At the end of the subsequent four-year cooling period, air-permeability decreases (to as low as 0.2 of initial) and increases (to as high as 1.8 of initial) were observed. By comparison to the calculated thermo-hydro-elastic model results, we identified these remaining increases or decreases in air permeability as irreversible changes in intrinsic fracture permeability, consistent with either inelastic fracture shear dilation (where permeability increased) or inelastic fracture surface asperity shortening (where permeability decreased). In this paper, we discuss the possibility that such fracture asperity shortening and associated decrease in fracture permeability might be enhanced by dissolution of highly stressed surface asperities over years of elevated stress and temperature.

Rutqvist, J.; Freifeld, B.; Min, K.-B.; Elsworth, D.; Tsang, Y.

2008-06-01T23:59:59.000Z

436

Optimizing Fracture Treatments in a Mississippian "Chat" Reservoir, South-Central Kansas  

SciTech Connect (OSTI)

This project is a collaboration of Woolsey Petroleum Corporation (a small independent operator) and the Kansas Geological Survey. The project will investigate geologic and engineering factors critical for designing hydraulic fracture treatments in Mississippian ''chat'' reservoirs. Mississippian reservoirs, including the chat, account for 159 million m3 (1 billion barrels) of the cumulative oil produced in Kansas. Mississippian reservoirs presently represent {approx}40% of the state's 5.6*106m3 (35 million barrels) annual production. Although geographically widespread, the ''chat'' is a heterogeneous reservoir composed of chert, cherty dolomite, and argillaceous limestone. Fractured chert with micro-moldic porosity is the best reservoir in this 18- to 30-m-thick (60- to 100-ft) unit. The chat will be cored in an infill well in the Medicine Lodge North field (417,638 m3 [2,626,858 bbls] oil; 217,811,000 m3 [7,692,010 mcf] gas cumulative production; discovered 1954). The core and modern wireline logs will provide geological and petrophysical data for designing a fracture treatment. Optimum hydraulic fracturing design is poorly defined in the chat, with poor correlation of treatment size to production increase. To establish new geologic and petrophysical guidelines for these treatments, data from core petrophysics, wireline logs, and oil-field maps will be input to a fracture-treatment simulation program. Parameters will be established for optimal size of the treatment and geologic characteristics of the predicted fracturing. The fracturing will be performed and subsequent wellsite tests will ascertain the results for comparison to predictions. A reservoir simulation program will then predict the rate and volumetric increase in production. Comparison of the predicted increase in production with that of reality, and the hypothetical fracturing behavior of the reservoir with that of its actual behavior, will serve as tests of the geologic and petrophysical characterization of the oil field. After this feedback, a second well will be cored and logged, and procedure will be repeated to test characteristics determined to be critical for designing cost-effective fracture treatments. Most oil and gas production in Kansas, and that of the Midcontinent oil industry, is dominated by small companies. The overwhelming majority of these independent operators employ less than 20 people. These companies have limited scientific and engineering expertise and they are increasingly needing guidelines and technical examples that will help them to not be wasteful of their limited financial resources and petroleum reserves. To aid these operators, the technology transfer capabilities of the Kansas Geological Survey will disseminate the results of this study to the local, regional, and national oil industry. Internet access, seminars, presentations, and publications by Woolsey Petroleum Company and Kansas Geological Survey geologists and engineers are anticipated.

K. David Newell; Saibal Bhattacharya; Alan Byrnes; W. Lynn Watney; Willard Guy

2005-10-01T23:59:59.000Z

437

Methodologies and new user interfaces to optimize hydraulic fracturing design and evaluate fracturing performance for gas wells  

E-Print Network [OSTI]

This thesis presents and develops efficient and effective methodologies for optimal hydraulic fracture design and fracture performance evaluation. These methods incorporate algorithms that simultaneously optimize all of the treatment parameters...

Wang, Wenxin

2006-04-12T23:59:59.000Z

438

Colloid-facilitated radionuclide transport in fractured porous rock  

E-Print Network [OSTI]

radionuclide on the fracture surface [kg ? nuclide / m' - surface]. 23 3. 4 The Radionuclide transport in the aqueous phase within the fracture The radionuclide transport in the aqueous phase within the fracture is expressed as: BN cf rr r ? +V J +VV...

Baek, Inseok

2012-06-07T23:59:59.000Z

439

Creation and Impairment of Hydraulic Fracture Conductivity in Shale Formations  

E-Print Network [OSTI]

Multi-stage hydraulic fracturing is the key to the success of many shale gas and shale oil reservoirs. The main objectives of hydraulic fracturing in shale are to create artificial fracture networks that are conductive for oil and gas flow...

Zhang, Junjing

2014-07-10T23:59:59.000Z

440

Estimating Major and Minor Natural Fracture Patterns in Gas  

E-Print Network [OSTI]

Estimating Major and Minor Natural Fracture Patterns in Gas Shales Using Production Data Razi Identification of infill drilling locations has been challenging with mixed results in gas shales. Natural fractures are the main source of permeability in gas shales. Natural fracture patterns in shale has a random

Mohaghegh, Shahab

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

New fluids help increase effectiveness of hydraulic fracturing  

SciTech Connect (OSTI)

It is important to choose the most effective fluid for hydraulic fracturing a particular formation. Fracturing fluids are used to initiate formation parting, extend the fracture into the reservoir, and to transport and distribute proppant. This paper discusses the fundamental of fluid types, viscosifiers, and fluid rheology.

Ebinger, C.D.; Hunt, E.

1989-06-05T23:59:59.000Z

442

Hydraulic Fractures: multiscale phenomena, asymptotic and numerical solutions  

E-Print Network [OSTI]

Hydraulic Fractures: multiscale phenomena, asymptotic and numerical solutions CSIRO CSS TCP Detournay (UMN) Eduard Siebrits (SLB) #12;2 Outline · Examples of hydraulic fractures · Governing equations well stimulation Fracturing Fluid Proppant #12;5 Quarries #12;6 Magma flow Tarkastad #12;7 Model EQ 1

Peirce, Anthony

443

Hydraulic Fractures: multiscale phenomena, asymptotic and numerical solutions  

E-Print Network [OSTI]

Hydraulic Fractures: multiscale phenomena, asymptotic and numerical solutions SANUM Conference (UMN) Eduard Siebrits (SLB) #12;2 Outline · Examples of hydraulic fractures · Governing equations well stimulation Fracturing Fluid Proppant #12;5 Quarries #12;6 Magma flow Tarkastad #12;7 Model EQ 1

Peirce, Anthony

444

Modeling Turbulent Hydraulic Fracture Near a Free Surface  

E-Print Network [OSTI]

Modeling Turbulent Hydraulic Fracture Near a Free Surface Victor C. Tsai Seismological Laboratory consider a hydraulic fracture problem in which the crack grows parallel to a free surface, subject to fully components. ^· Non-dimensionalized ·. 1 Introduction Hydraulic fracture has been studied for many years

445

Role of seepage forces on hydraulic fracturing and failure patterns  

E-Print Network [OSTI]

Role of seepage forces on hydraulic fracturing and failure patterns Alexander Rozhko Thesis September 2007 #12;ii Role of seepage forces on hydraulic fracturing and failure patterns Abstract. The mechanical role of seepage forces on hydraulic fracturing and failure patterns was studied both

Paris-Sud XI, Université de

446

Modeling Turbulent Hydraulic Fracture Near a Free Surface  

E-Print Network [OSTI]

Modeling Turbulent Hydraulic Fracture Near a Free Surface Victor C. Tsai Seismological Laboratory consider a hydraulic fracture problem in which the crack grows parallel to a free surface, subject to fully components. wall Wall shear stress. ^· Non-dimensionalized ·. 1 Introduction Hydraulic fracture has been

447

CLEAVAGE FRACTURE MICROMECHANISMS RELATED TO WPS EFFECT IN RPV STEEL  

E-Print Network [OSTI]

CLEAVAGE FRACTURE MICROMECHANISMS RELATED TO WPS EFFECT IN RPV STEEL S. R. Bordet1 , B. Tanguy1 , S by warm pre-stress (WPS) on the cleavage fracture micromechanisms of a 18MND5 (A533B) reactor pressure vessel (RPV) steel. In this purpose, different WPS fracture test results obtained on compact tensile (CT

Boyer, Edmond

448

Introduction Fracture at small length scales is a concern  

E-Print Network [OSTI]

Introduction Fracture at small length scales is a concern in many advanced technologies. Micro. These constrained geometries localize cracking so that fracture may not compromise the structural integrity functions. For example, lo- calized fracture of a dielectric film adjacent to a conducting line

Suo, Zhigang

449

Scaling of fracture length and distributed damage Vladimir Lyakhovsky  

E-Print Network [OSTI]

Scaling of fracture length and distributed damage Vladimir Lyakhovsky The Institute of Earth space scaling except linear relations between fracture length and displacements and thus the determination theoretically of the strength of a body or structure directly. Self-similarity of a fracture

Lyakhovsky, Vladimir

450

Fracture patterns in thin films and multilayers Alex A. Volinsky  

E-Print Network [OSTI]

Fracture patterns in thin films and multilayers Alex A. Volinsky University of South Florida, excessive residual and externally applied stresses cause film fracture. In the case of tensile stress is the key for causing thin film fracture, either in tension, or compression, it is the influence

Volinsky, Alex A.

451

Monitoring of Fracture Cri0cal Steel Bridges  

E-Print Network [OSTI]

#12;Monitoring of Fracture Cri0cal Steel Bridges: Acous0c Emission Sensors Fracture System Needs to Iden0fy: · Crack Ini0a0on · Crack Propaga0on · Weld Fracture Advanced Warning of Structural Distress #12;Technology Selec0on: Acous0c

Minnesota, University of

452

Structured Deformations as Energy Minimizers in Models of Fracture and  

E-Print Network [OSTI]

Structured Deformations as Energy Minimizers in Models of Fracture and Hysteresis R. Choksi and for a bar experiencing both smooth exten- sion and macroscopic fractures then are determined, and applications to the shearing of single crystals and to the cohesive fracture of solids are discussed. Yield

453

Automatic Fracture Reduction Thomas Albrecht and Thomas Vetter  

E-Print Network [OSTI]

Automatic Fracture Reduction Thomas Albrecht and Thomas Vetter University of Basel Abstract. We segmented from CT scans. The result of this virtual fracture reduction is intended to be used an operation plan. We propose to achieve automatic fracture reduction by fitting the bone fragments

Vetter, Thomas

454

Fracture aperture reconstruction and determination of hydrological properties: a  

E-Print Network [OSTI]

Fracture aperture reconstruction and determination of hydrological properties: a case study for fracture aperture reconstruction. The rst one is a correlation technique that estimates the normal aper techniques are applied to discontinuities extracted from a core drilled down to 20 m in a fractured marl

Toussaint, Renaud

455

Geometric fracture modeling in BOLT Jeffrey Hellrung1  

E-Print Network [OSTI]

Geometric fracture modeling in BOLT Jeffrey Hellrung1 Andrew Selle2 Arthur Shek2 Eftychios Sifakis1 from the un-fractured model. 2 Crack geometry generation The input to our system consists of a closed triangulated surface defining the (uncut) solid object to be fractured and one or more ad- ditional

Liblit, Ben

456

Fracture Toughness of MDF and other Materials with Fiber Bridging  

E-Print Network [OSTI]

Fracture Toughness of MDF and other Materials with Fiber Bridging Noah Matsumoto and John A. Nairn* ABSTRACT We measured the fracture toughness of MDF panels with two different densities by using crack propagation experiments and energy-based fracture mechanics. The two challenges were to identify the energy

Nairn, John A.

457

EXPERIMENTAL INVESTIGATION OF BOILING HEAT CONVECTION IN A FRACTURE  

E-Print Network [OSTI]

EXPERIMENTAL INVESTIGATION OF BOILING HEAT CONVECTION IN A FRACTURE A REPORT SUBMITTED between heat conduction and heat convection with boiling flow in a rock fracture. An experimental coefficient. This coefficient is the proportionality factor between the heat flux to a fracture surface

Stanford University

458

SCALING OF FRACTURE SYSTEMS IN GEOLOGICAL MEDIA E. Bonnet,1  

E-Print Network [OSTI]

SCALING OF FRACTURE SYSTEMS IN GEOLOGICAL MEDIA E. Bonnet,1 O. Bour,2 N. E. Odling,1,3 P. Davy,2 I. Main,4 P. Cowie,4 and B. Berkowitz5 Abstract. Scaling in fracture systems has become an active field spread widely through the literature. Although it is rec- ognized that some fracture systems are best

Cowie, Patience

459

Fibre Based Modeling of Wood Dynamics and Fracture  

E-Print Network [OSTI]

Fibre Based Modeling of Wood Dynamics and Fracture by Sean Meiji Sutherland B.Sc., The University for the simulation of the dynamics and fracturing char- acteristics of wood, specifically its anisotropic behaviour bundles of fibres. Additionally, we describe the conditions under which fracture occurs in the material

Bridson, Robert

460

In vitro fracture toughness of human dentin V. Imbeni,1  

E-Print Network [OSTI]

In vitro fracture toughness of human dentin V. Imbeni,1 R. K. Nalla,1 C. Bosi,1 J. H. Kinney,2 R. O August 2002 Abstract: The in vitro fracture toughness of human dentin has been reported measured crit- ical stress intensity, Kc, for the onset of unstable fracture along an orientation

Ritchie, Robert

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Fracture surface energy of the Punchbowl fault, San Andreas system  

E-Print Network [OSTI]

Fracture surface energy of the Punchbowl fault, San Andreas system Judith S. Chester1 , Frederick M. Chester1 & Andreas K. Kronenberg1 Fracture energy is a form of latent heat required to create weakening1­3 . Fracture energy has been estimated from seismological and experimental rock deformation data4

Chester, Frederick M.

462

THE EFFECT OF SURFACE TENSION IN MODELING INTERFACIAL FRACTURE  

E-Print Network [OSTI]

THE EFFECT OF SURFACE TENSION IN MODELING INTERFACIAL FRACTURE By Tsvetanka Sendova and Jay R Fracture Tsvetanka Sendova and Jay R. Walton Institute for Mathematics and Its Applications, University@math.tamu.edu Abstract. In this article the problem of an interface fracture between two isotropic linear elas- tic

463

The use of seismic anisotropy for characterizing subsurface fracture ori-  

E-Print Network [OSTI]

The use of seismic anisotropy for characterizing subsurface fracture ori- entations and intensity anisotropy as a routine technique for fracture characterization is partly because of its inability to pro- vide information about sizes and vol- ume of fractures. Although both grain-scale micro

Edinburgh, University of

464

6. Fracture mechanics lead author: J, R. Rice  

E-Print Network [OSTI]

6. Fracture mechanics lead author: J, R. Rice Division of Applied Sciences, Harvard University. F. Shih, and the ASME/AMD Technical Committee on Fracture Mechanics, pro- vided by A. S. Argon, S. N, W. D. Stuart, and R. Thomson. 6.0 ABSTRACT Fracture mechanics is an active research field

465

Femoral neck fracture prediction by anisotropic yield criteria  

E-Print Network [OSTI]

Femoral neck fracture prediction by anisotropic yield criteria M. Tellache a , b , M. Pithioux and increases its porosity. Hip fractures are the more recurrent consequences of osteoporosis, and are the cause of morbidity and increase the rate of mortality. The fracture risk due to osteoporosis, is undertaken with Dual

Paris-Sud XI, Université de

466

Geomechanical Development of Fractured Reservoirs During Gas Production  

E-Print Network [OSTI]

for deformation and fluid flow within matrix domain; while the other is the fracture element simulating the fluid flow only through the fractures. Both matrix and fractures are assumed to be permeable and can accomodate fluid transported. A quasi steady-state...

Huang, Jian

2013-04-05T23:59:59.000Z

467

Laboratory experiments simulating fire flooding through a fractured reservoir  

SciTech Connect (OSTI)

Low-permeability heavy-oil reservoirs are considered to be poor prospects for in-situ-combustion recovery methods. The low-permeability, high-viscosity heavy oils, combined, make air injection through the formation insufficient to support combustion in the formation. The objective of this research is to show results obtained through burn tests on whole cores and fractured cores relating these results to heavy-oil reservoirs. These tests were performed to determine the technical feasibility of recovering heavy oil by the in-situ-combustion process from reservoirs which are shallow and contain no reservoir energy. These tests were conducted on cores obtained from a heavy-oil reservoir near Bartlett, Kansas. The tests were performed in a thin-walled core holder with a built-in heater to start combustion. Air was measured and injected through the heater and into the core. The produced fluids (oil and water) were obtained and measured and the resulting effluent gas was measured and analyzed on a chromatograph to determine the constituents of the produced gas. The injected air pressure was determined and temperature logs were plotted during the entire test. It was determined from the results of the tests on competent cores that 78 percent of the oil was removed from the cores as a result of the in-situ-combustion process on competent cores while 16 percent was used as fuel for combustion. The results from the tests on fractured cores show that 33 percent of the oil was removed from the cores as a result of the in-situ-combustion process while 45 percent was used as fuel for combustion. The results from the tests on fractured cores held apart by propping agents show that 16 percent of the oil was removed from the cores as a result of the in-situ-combustion process, while 38 percent was used as fuel to support combustion. 46 figures, 56 tables.

Miller, J.S.; Jones, R.

1983-04-01T23:59:59.000Z

468

Diagnosis and evaluation of fracturing treatments  

SciTech Connect (OSTI)

This paper introduces the pressure derivative in fracturing-pressure analysis for oil wells. The derivative is shown to enhance the analysis capabilities significantly. The interpretation methodology is presented, and several field data sets and simulations are discussed to illustrate to technique.

Barree, R.D. (Marathon Oil Co. (US)); Ayoub, J.A.; Brown, J.E.; Elphick, J.J. (Dowell Schlumberger (US))

1992-02-01T23:59:59.000Z

469

Boiling Radial Flow in Fractures of Varying  

E-Print Network [OSTI]

the surface, within the matrix. The depth of boiling was a function of injection rate, thermal power supplied coupled to injection rate into the fracture. However, for porous surfaces, heat flux, and associated values of excess temperature and a boiling convection coefficient exhibited variation with injection rate

Stanford University

470

Interference Fracturing: Non-Uniform Distributions of Perforation Clusters that Promote Simultaneous Growth of Multiple Hydraulic Fractures  

E-Print Network [OSTI]

Simultaneous Growth of Multiple Hydraulic Fractures A.P. Peirce, University of British Columbia and A.P. Bunger in horizontal well stimulation is the generation of hydraulic fractures (HFs) from all perforation clusters shadowing" that refers to suppression of some hydraulic fractures by the compressive stresses exerted

Peirce, Anthony

471

Inversion of Scattered Waves for Material Properties in Fractured Rock  

SciTech Connect (OSTI)

The authors apply a recently developed low-frequency, non-linear inversion method which includes near and far field terms to a crosshole data set to determine the bulk and shear modulus, as well as the density for a fractured zone in a granitic rock mass. The method uses the scattered elastic wavefield which is extracted from the recorded data before the inversion is performed. The inversion result is appraised by investigating the resolution and standard deviation of the model estimates. The sensitivity of the three parameters to different features of the medium is revealed. While the bulk modulus appears to be sensitive to voids and welded contacts, the density is mostly affected by fractured zones. The shear modulus is least constrained due to the absence of S wave anisotropy information. It is shown that the three medium parameters are generally sensitive to other medium features than those determined by velocity inversions. Thus this method is viewed as a complimentary approach to travel time tomography which provides more insight into the material properties of inhomogeneous media.

Gritto, Roland; Korneev, Valeri A.; Johnson, Lane R.

1999-07-01T23:59:59.000Z

472

Microseismicity, stress, and fracture in the Coso geothermal field,  

Open Energy Info (EERE)

Microseismicity, stress, and fracture in the Coso geothermal field, Microseismicity, stress, and fracture in the Coso geothermal field, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Microseismicity, stress, and fracture in the Coso geothermal field, California Details Activities (1) Areas (1) Regions (0) Abstract: Microseismicity, stress, and fracture in the Coso geothermal field are investigated using seismicity, focal mechanisms and stress analysis. Comparison of hypocenters of microearthquakes with locations of development wells indicates that microseismic activity has increased since the commencement of fluid injection and circulation. Microearthquakes in the geothermal field are proposed as indicators of shear fracturing associated with fluid injection and circulation along major pre-existing

473

Hydraulic fracturing in a sedimentary geothermal reservoir: Results and implications  

Science Journals Connector (OSTI)

Field experiments in a geothermal research well were conducted to enhance the inflow performance of a clastic sedimentary reservoir section. Due to depths exceeding 4050 m, bottom hole temperatures exceeding 140 °C, and open hole section (dual zone), technically demanding and somewhat unprecedented conditions had to be managed. The fracturing operations were successful. Fractures were created in two isolated borehole intervals and the inflow behaviour of the reservoir was decisively enhanced. The effective pressures applied for fracture initiation and propagation were only slightly above in situ pore pressures. Nevertheless, the stimulation ratio predicted by fracture performance modelling could not be achieved. Multiple reasons could be identified that account for the mismatch. An insufficient fracture tie-back, as well as chemical and mechanical processes during closure, led to reduced fracture conductivities and therefore diminished productivity. The insights gained are the basis for further fracture design concepts at the given and geologic comparable sites.

B. Legarth; E. Huenges; G. Zimmermann

2005-01-01T23:59:59.000Z

474

Fracture behavior of zircaloy spent-fuel cladding  

SciTech Connect (OSTI)

The Zircaloy cladding of water reactor fuel rods is susceptible to local breach-type failure, commonly known as pellet-cladding interaction (PCI) failure, during operational and off-normal power transients after the fuel has achieved a sufficiently high burnup. An optimization of power ramp procedures or fuel rod fabrication to minimize the cladding failure would result in a significant decrease in radiation exposure of plant personnel due to background and airborne radioactivity as well as an extension of core life in terms of allowable off-gas radioactivity. As part of a program to provide a better understanding of the fuel rod faiure phenomenon and to facilitate the formulation of a better failure criterion, a mechanistic study of the deformation and fracture behavior of high-burnup spent-fuel cladding is in progress under simulated PCI conditions.

Chung, H.M.; Yaggee, F.L.; Kassner, T.F.

1983-10-01T23:59:59.000Z

475

Dilatancy in the flow and fracture of stretched colloidal suspensions  

E-Print Network [OSTI]

Concentrated particulate suspensions, commonplace in the pharmaceutical, cosmetic and food industries, display intriguing rheology. In particular, the dramatic increase in viscosity with strain rate (shear thickening and jamming) which is often observed at high volume fractions, is of strong practical and fundamental importance. Yet manufacture of these products and their subsequent dispensing often involves flow geometries substantially different from that of simple shear flow experiments. Here we show that the elongation and breakage of a filament of a colloidal fluid under tensile loading is closely related to the jamming transition seen in its shear rheology. However, the modified flow geometry reveals important additional effects. Using a model system with nearly hard-core interactions, we provide evidence of surprisingly strong viscoelasticity in such a colloidal fluid under tension. With high speed photography we also directly observe dilatancy and granulation effects, which lead to fracture above a critical elongation rate.

M. I. Smith; R. Besseling; M. E. Cates; V. Bertola

2011-01-12T23:59:59.000Z

476

Scaling Up – From Material Fracture Resistance to Fracture Representation in Welded Structures  

Science Journals Connector (OSTI)

Abstract This paper presents a procedure to integrate the material fracture resistance, quantified by the experimentally measured J-R curve, in the fracture representation of welded tubular joints. This method incorporates a validated ?-approach to estimate the elastic-plastic crack driving forces for fatigue cracks initiated at hot-spot locations of the welded tubular joints. The proposed scaling approach predicates on the fundamental assumption that the fracture resistance measured from the J-R curve, with a small and limited amount of crack extension, characterizes the material fracture resistance independent of the specimen geometry. The maximum crack extension allowed in the material testing standard marks the transferability limit of the material J-R curve to the welded joints. The extension of the fatigue crack in the welded joint leads to an increasing fracture resistance and a decreasing load resistance due to the increased crack area. The validation of this approach utilizes load-deformation responses from two scales of experimental specimens: 1) the large-scale welded tubular connection with a fatigue pre-crack; and 2) the large-scale frame test with predominantly fracture failure at the welded tubular joint. The load-deformation relationship based on the proposed scheme presents a close agreement with the experimentally recorded load-deformation behavior of the welded tubular joints. The proposed approach, when integrated into the push-over analyses of the large-scale tubular frames, presents an accurate estimation on the deformation level at which unstable fracture failure occurs and a conservative prediction of the corresponding failure load.

Xudong Qian; Yang Zhang; Ya Li

2014-01-01T23:59:59.000Z

477

Measuring the Fracture Toughness of TZM and ODS Molybdenum Alloys Using Standard and Sub-Sized Bend Specimens  

SciTech Connect (OSTI)

Oxide Dispersion Strengthened (ODS) and TZM molybdenum have excellent creep resistance and strength at high temperatures in inert atmospheres. Fracture toughness and tensile testing was performed at temperatures between -150 degrees C and 450 degrees C to characterize 6.35 mm thick plate material of ODS and TZM molybdenum. A transition from low fracture toughness values (5.8 to 29.6 MPa square root m) to values greater than 30 MPa square root m is observed for TZM molybdenum in the longitudinal orientation at 100 degrees C and in the transverse orientation at 150 degrees C. These results are consistent with data reported in literature for molybdenum. A transition to low fracture toughness values (less than 30 MPa square root m) was not observed for longitudinal ODS molybdenum at temperatures greater than or equal to -150 degrees C, while a transition to low fracture toughness values (12.6 to 25.4 MPa square root m) was observed for the transverse orientation at room-temperature. The fi ne spacing of La-oxide precipitates that are present in ODS molybdenum result in a transition temperature that is significantly lower than any molybdenum alloy reported to date, with upper bound fracture toughness values that bound the literature data. A comparison of fracture toughness values obtained using a 1T, 0.5T, and 0.25T Charpy shows that a 0.5T Charpy could be used as a sub-sized specimen geometry.

Cockeram, B. V.

2002-12-01T23:59:59.000Z

478

Determination of Transport Properties From Flowing Fluid Temperature LoggingIn Unsaturated Fractured Rocks: Theory And Semi-Analytical Solution  

SciTech Connect (OSTI)

Flowing fluid temperature logging (FFTL) has been recently proposed as a method to locate flowing fractures. We argue that FFTL, backed up by data from high-precision distributed temperature sensors, can be a useful tool in locating flowing fractures and in estimating the transport properties of unsaturated fractured rocks. We have developed the theoretical background needed to analyze data from FFTL. In this paper, we present a simplified conceptualization of FFTL in unsaturated fractured rock, and develop a semianalytical solution for spatial and temporal variations of pressure and temperature inside a borehole in response to an applied perturbation (pumping of air from the borehole). We compare the semi-analytical solution with predictions from the TOUGH2 numerical simulator. Based on the semi-analytical solution, we propose a method to estimate the permeability of the fracture continuum surrounding the borehole. Using this proposed method, we estimated the effective fracture continuum permeability of the unsaturated rock hosting the Drift Scale Test (DST) at Yucca Mountain, Nevada. Our estimate compares well with previous independent estimates for fracture permeability of the DST host rock. The conceptual model of FFTL presented in this paper is based on the assumptions of single-phase flow, convection-only heat transfer, and negligible change in system state of the rock formation. In a sequel paper [Mukhopadhyay et al., 2008], we extend the conceptual model to evaluate some of these assumptions. We also perform inverse modeling of FFTL data to estimate, in addition to permeability, other transport parameters (such as porosity and thermal conductivity) of unsaturated fractured rocks.

Mukhopadhyay, Sumit; Tsang, Yvonne W.

2008-08-01T23:59:59.000Z

479

The influence of fluid properties on the success of hydraulic fracturing operations  

SciTech Connect (OSTI)

Hydroxypropylguar based fluids are the most commonly used fluids for hydraulic fracturing. Through the addition of borate ions the polymer present in the fluid can crosslink to form a high viscosity gel. Prior to placement in the fracture the fluid is required to have a low viscosity to minimize friction losses in the tubular goods. A high viscosity fluid is required in the fracture for several reasons, primarily to suspend the proppant and to minimize fluid loss into the formation. This paper describes a new method which can be used to model the gelation reaction of crosslinking fluids. By modeling the dynamic properties of the fluid it is possible to predict the physical state of the fluid at any time during a fracturing treatment. Small amplitude oscillatory measurements are applied to fluid samples in a cone-and-plate geometry. The change in the dynamic properties with time can be fitted to a simple model which can then be used to determine the gel time for the fluid. Methods used to distinguish between the liquid and gel state are also discussed.

Power, D.J.; Boger, D.V. [Univ. of Melbourne, Victoria (Australia); Paterson, L.

1994-12-31T23:59:59.000Z

480

Mode I fracture of a biopolymer gel: rate-dependent dissipation and large deformations disentangled  

E-Print Network [OSTI]

We have designed a new experimental setup able to investigate fracture of soft materials at small scales. At high crack velocity, where energy is mostly dissipated through viscoelastic processes, we observe an increasingly large high strain domain in the crack tip vicinity. Taking advantage of our ability to determine where linear elasticity breaks down, we derive a simple prediction for the evolution of the energy release rate with the crack velocity.

Maxime Lefranc; Elisabeth Bouchaud

2015-01-06T23:59:59.000Z

Note: This page contains sample records for the topic "including highly fractured" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Fracture simulation for zirconia toughened alumina microstructure  

E-Print Network [OSTI]

Purpose - The purpose of this paper is to describe finite element modelling for fracture and fatigue behaviour of zirconia toughened alumina microstructures. Design/methodology/approach - A two-dimensional finite element model is developed with an actual $Al{_2}O{_3}$ - 10 vol% $ZrO{_2}$ microstructure. A bilinear, time-independent cohesive zone law is implemented for describing fracture behaviour of grain boundaries. Simulation conditions are similar to those found at contact between a head and a cup of hip prosthesis. Residual stresses arisen from the mismatch of thermal coefficient between grains are determined. Then, effects of a micro-void and contact stress magnitude are investigated with models containing residual stresses. For the purpose of simulating fatigue behaviour, cyclic loadings are applied to the models. Findings - Results show that crack density is gradually increased with increasing magnitude of contact stress or number of fatigue cycles. It is also identified that a micro-void brings about...

Kim, Kyungmok; Forest, Bernard

2013-01-01T23:59:59.000Z

482

Correlating toughness and roughness in ductile fracture  

E-Print Network [OSTI]

Three dimensional calculations of ductile crack growth under mode I plane strain, small scale yielding conditions are carried out using an elastic-viscoplastic constitutive relation for a progres- sively cavitating plastic solid with two populations of void nucleating second phase particles. Full field solutions are obtained for three dimensional material microstructures characterized by ran- dom distributions of void nucleating particles. Crack growth resistance curves and fracture surface roughness statistics are calculated using standard procedures. The range of void nucleating particle volume fractions considered give rise to values of toughness, JIC, that vary by a factor of four. For all volume fractions considered, the computed fracture surfaces are self-affine over a size range of about two orders of magnitude with a roughness exponent of 0.54 $\\pm$ 0.03. For small void nucleating particle volume fractions, the mean large particle spacing serves as a single dominant length scale. In this regime, the c...

Ponson, Laurent; Osovski, Shmulik; Bouchaud, Elisabeth; Tvergaard, Viggo; Needleman, Alan

2013-01-01T23:59:59.000Z

483

Naturally fractured tight gas reservoir detection optimization  

SciTech Connect (OSTI)

Building upon the partitioning of the Greater Green River Basin (GGRB) that was conducted last quarter, the goal of the work this quarter has been to conclude evaluation of the Stratos well and the prototypical Green River Deep partition, and perform the fill resource evaluation of the Upper Cretaceous tight gas play, with the goal of defining target areas of enhanced natural fracturing. The work plan for the quarter of November 1-December 31, 1998 comprised four tasks: (1) Evaluation of the Green River Deep partition and the Stratos well and examination of potential opportunity for expanding the use of E and P technology to low permeability, naturally fractured gas reservoirs, (2) Gas field studies, and (3) Resource analysis of the balance of the partitions.

NONE

1999-06-01T23:59:59.000Z

484

How intense quality control improves hydraulic fracturing  

SciTech Connect (OSTI)

Not unlike the subject of Forced Closure, Intense Quality Control is probably misnamed. What actually is discussed in this article is pilot testing of the fracturing fluids actually pumped at in-situ conditions of temperature and shear. Presented here is development of the need for onsite testing, equipment used, shear and viscosity curves from several jobs showing what went wrong that would otherwise not have been known, and a discussion of borate gel fluids.

Ely, J.W. [Ely and Associates, Inc., Houston, TX (United States)

1996-11-01T23:59:59.000Z

485

Fracture toughness of thick section dissimilar electron beam weld joints  

SciTech Connect (OSTI)

Microstructural investigations as well as crack tip opening displacement (CTOD) fracture toughness test based on elastic-plastic fracture mechanics were performed on single pass, full penetration similar and dissimilar electron beam (EB) welds of 40 mm thick 316L type austenitic steel and high alloyed fine tempered martensitic 9Cr 1Mo Nb V (P91 -ASTM A213) steel. The latter modified steel has been developed to fill up the gap between 12Cr steel and austenitic stainless steels with respect to the high temperature properties and better weldability. Furthermore, it shows a small thermal expansion coefficient and is not susceptible to stress corrosion cracking like the austenitic steel. The weldment properties were evaluated by microstructural analysis, microhardness, Charpy V- notch impact, and by newly developed flat microtensile specimens (0.5 mm thick). The dissimilar EB weld metal and HAZ of P91 steel has been shown to be microstructurally and mechanically distinct from both austenitic and martenistic parent metals. The use of microsized rectangular tensile specimens provides unique solution to the problem of the mechanical property determination of the narrow EB weld joint. The HAZ of the 9Cr1Mo steel exhibits extremely poor CTOD toughness properties in as-welded condition at room temperature. The CTOD values obtained were believed to be represent the intrinsic property of this zone, since the distance of the crack tip to the austenitic steel part was too large to receive a stress relaxation effect from low strength side on the crack tip (by accommodating the applied strains in the high toughness, lower strength 316L plate).

Kocak, M.; Junghans, E.

1994-12-31T23:59:59.000Z

486

FRACTURE FAILURE CRITERIA OF SOFC PEN STRUCTURE  

SciTech Connect (OSTI)

Thermal stresses and warpage of the PEN are unavoidable due to the temperature changes from the stress-free sintering temperature to room temperature and mismatch of the coefficients of thermal expansion (CTE) of various layers in the PEN structures of solid oxide fuel cells (SOFC) during the PEN manufacturing process. In the meantime, additional mechanical stresses will also be created by mechanical flattening during the stack assembly process. The porous nature of anode and cathode in the PEN structures determines presence of the initial flaws and crack on the interfaces of anode/electrolyte/cathode and in the interior of the materials. The sintering/assembling induced stresses may cause the fracture failure of PEN structure. Therefore, fracture failure criteria for SOFC PEN structures is developed in order to ensure the structural integrity of the cell and stack of SOFC. In this paper, the fracture criteria based on the relationship between the critical energy release rate and critical curvature and maximum displacement of the warped cells caused by the temperature changes as well as mechanical flattening process is established so that possible failure of SOFC PEN structures may be predicted deterministically by the measurement of the curvature and displacement of the warped cells.

Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.; Qu, Jianmin

2007-04-30T23:59:59.000Z

487

Determining Ductile Fracture Toughness in Metals  

SciTech Connect (OSTI)

Ductile fracture toughness determination, such as the J-integral versus crack growth resistance (J-R) curve, is a useful tool for evaluating material structural integrity in the presence of pre-existing defects. The J-R curve represents a way to calculate the work (energy) per unit fracture surface area needed to drive the crack growth. A typical J-R curve is shown in Fig. 1 from which the material fracture toughness near the initiation of stable crack growth (Jq) can be derived. In addition, tearing modulus (TR), representing the material resistance to stable crack growth, can be calculated based on the slope of the J-R curve between two exclusion lines (red dashed lines in Fig. 1). Since the introduction of the J-R curve, extensive efforts have been continuously devoted to develop simplified and reliable methods for determining the material J-R curve. This article briefly reviews three widely-used J-R curve test methods in metals, i.e. elastic unloading compliance (EUC), normalization, and direct current potential drop (DCPD). The main difference in these methods relates to the determination of the crack size. More details of performing the J-R curve determination can be found in ASTM standard E1820-11.

Chen, Xiang [ORNL] [ORNL; Nanstad, Randy K [ORNL] [ORNL; Sokolov, Mikhail A [ORNL] [ORNL; Manneschmidt, Eric T [ORNL] [ORNL

2014-01-01T23:59:59.000Z

488

Influence of wet underwater welding on fracture values  

SciTech Connect (OSTI)

The fracture behavior of welds is influenced by residual stresses. The influence of residual stresses on fracture parameters is investigated through the comparison of wet underwater welds, dry welds and welds without residual stresses. The fracture parameters for a sharp, stationary crack on the surface of a bead on plate weld under bending are determined by the finite element method. The geometric influence of weld on fracture parameters is investigated. The stress intensity factor for linear elastic fracture mechanics, the J-integral and the crack tip opening displacement for plastic fracture mechanics are calculated. The material behavior is assumed as linear elastic or linear elastic/ideal plastic or elastic plastic with multilinear isotropic hardening. The numerical data are compared with the experiments.

Lindhorst, L.; Hamann, R.; Mahrenholtz, O. [Technical Univ. of Hamburg-Harburg, Hamburg (Germany). Offshore Engineering Section 2; Kocak, M. [GKSS Research Center, Geesthacht (Germany). Inst. of Material Research

1995-12-31T23:59:59.000Z

489

Intrusion Margins and Associated Fractures | Open Energy Information  

Open Energy Info (EERE)

Intrusion Margins and Associated Fractures Intrusion Margins and Associated Fractures Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Intrusion Margins and Associated Fractures Dictionary.png Intrusion Margins and Associated Fractures: No definition has been provided for this term. Add a Definition Controlling Structures List of controlling structures typically associated with geothermal systems: Major Normal Fault Termination of a Major Normal Fault Stepover or Relay Ramp in Normal Fault Zones Apex or Salient of Normal Fault Fault Intersection Accommodation Zone Displacement Transfer Zone Pull-Apart in Strike-Slip Fault Zone Intrusion Margins and Associated Fractures Stratigraphic Boundaries Fissure Swarms Caldera Rim Margins Lithologically Controlled Fractures caused by igneous activity creates permeability, allowing water

490