National Library of Energy BETA

Sample records for fracturing technology cxs

  1. Microearthquake Technology for EGS Fracture Characterization...

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

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

  2. Detecting Fractures Using Technology at High Temperatures and...

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

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

  3. Northwestern University Technological Institute Tight Shale Gas-Hydraulic Fracturing

    E-Print Network [OSTI]

    Guo, Dongning

    Northwestern University Technological Institute Tight Shale Gas-Hydraulic Fracturing Seminar Series fracturing of horizontal wells is priceless Sidney Green, London Shale Gas Summit, 2010 #12;Vertical Well

  4. Geomechanical review of hydraulic fracturing technology

    E-Print Network [OSTI]

    Arop, Julius Bankong

    2013-01-01

    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 documented in literature on the subject. The ...

  5. Advanced Hydraulic Fracturing Technology for Unconventional Tight Gas Reservoirs

    SciTech Connect (OSTI)

    Stephen Holditch; A. Daniel Hill; D. Zhu

    2007-06-19

    The objectives of this project are to develop and test new techniques for creating extensive, conductive hydraulic fractures in unconventional tight gas reservoirs by statistically assessing the productivity achieved in hundreds of field treatments with a variety of current fracturing practices ranging from 'water fracs' to conventional gel fracture treatments; by laboratory measurements of the conductivity created with high rate proppant fracturing using an entirely new conductivity test - the 'dynamic fracture conductivity test'; and by developing design models to implement the optimal fracture treatments determined from the field assessment and the laboratory measurements. One of the tasks of this project is to create an 'advisor' or expert system for completion, production and stimulation of tight gas reservoirs. A central part of this study is an extensive survey of the productivity of hundreds of tight gas wells that have been hydraulically fractured. We have been doing an extensive literature search of the SPE eLibrary, DOE, Gas Technology Institute (GTI), Bureau of Economic Geology and IHS Energy, for publicly available technical reports about procedures of drilling, completion and production of the tight gas wells. We have downloaded numerous papers and read and summarized the information to build a database that will contain field treatment data, organized by geographic location, and hydraulic fracture treatment design data, organized by the treatment type. We have conducted experimental study on 'dynamic fracture conductivity' created when proppant slurries are pumped into hydraulic fractures in tight gas sands. Unlike conventional fracture conductivity tests in which proppant is loaded into the fracture artificially; we pump proppant/frac fluid slurries into a fracture cell, dynamically placing the proppant just as it occurs in the field. From such tests, we expect to gain new insights into some of the critical issues in tight gas fracturing, in particular the roles of gel damage, polymer loading (water-frac versus gel frac), and proppant concentration on the created fracture conductivity. To achieve this objective, we have designed the experimental apparatus to conduct the dynamic fracture conductivity tests. The experimental apparatus has been built and some preliminary tests have been conducted to test the apparatus.

  6. Northwestern University Technological Institute Tight Shale Gas-Hydraulic Fracturing

    E-Print Network [OSTI]

    Guo, Dongning

    Northwestern University Technological Institute Tight Shale Gas-Hydraulic Fracturing Seminar Series Where are we Today: Reservoir and Completion Quality Is Tight Shale Gas and Oil the Answer ? Sidney and with different economic and environmental impacts · Tight Shale Gas and Oil is at least part of the answer

  7. Heavy Section Steel Technology HSST eLib Computational Structural Fracture Mechanics Team

    E-Print Network [OSTI]

    Heavy Section Steel Technology ­ HSST eLib Computational Structural Fracture Mechanics Team and engineering, and within our Computational Structural Fracture Mechanics Team we have been developing an electronic document repository library for research in the field of computational fracture mechanics applied

  8. FIELD TESTING & OPTIMIZATION OF CO2/SAND FRACTURING TECHNOLOGY

    SciTech Connect (OSTI)

    Raymond L. Mazza

    2004-11-30

    These contract efforts involved the demonstration of a unique liquid free stimulation technology which was, at the beginning of these efforts, in 1993 unavailable in the US. The process had been developed, and patented in Canada in 1981, and held promise for stimulating liquid sensitive reservoirs in the US. The technology differs from that conventionally used in that liquid carbon dioxide (CO{sub 2}), instead of water is the base fluid. The CO{sub 2} is pumped as a liquid and then vaporizes at reservoir conditions, and because no other liquids or chemicals are used, a liquid free fracture is created. The process requires a specialized closed system blender to mix the liquid CO{sub 2} with proppant under pressure. These efforts were funded to consist of up to 21 cost-shared stimulation events. Because of the vagaries of CO{sub 2} supplies, service company support and operator interest only 19 stimulation events were performed in Montana, New Mexico, and Texas. Final reports have been prepared for each of the four demonstration groups, and the specifics of those demonstrations are summarized. A summary of the demonstrations of a novel liquid-free stimulation process which was performed in four groups of ''Candidate Wells'' situated in Crockett Co., TX; San Juan Co., NM; Phillips Co., MT; and Blaine Co., MT. The stimulation process which employs CO{sub 2} as the working fluid and the production responses were compared with those from wells treated with conventional stimulation technologies, primarily N{sub 2} foam, excepting those in Blaine Co., MT where the reservoir pressure is too low to clean up spent stimulation liquids. A total of 19 liquid-free CO{sub 2}/sand stimulations were performed in 16 wells and the production improvements were generally uneconomic.

  9. NEW AND NOVEL FRACTURE STIMULATION TECHNOLOGIES FOR THE REVITALIZATION OF EXISTING GAS STORAGE WELLS

    SciTech Connect (OSTI)

    Unknown

    1999-12-01

    Gas storage wells are prone to continued deliverability loss at a reported average rate of 5% per annum (in the U.S.). This is a result of formation damage due to the introduction of foreign materials during gas injection, scale deposition and/or fines mobilization during gas withdrawal, and even the formation and growth of bacteria. As a means to bypass this damage and sustain/enhance well deliverability, several new and novel fracture stimulation technologies were tested in gas storage fields across the U.S. as part of a joint U.S. Department of Energy and Gas Research Institute R&D program. These new technologies include tip-screenout fracturing, hydraulic fracturing with liquid CO{sub 2} and proppant, extreme overbalance fracturing, and high-energy gas fracturing. Each of these technologies in some way address concerns with fracturing on the part of gas storage operators, such as fracture height growth, high permeability formations, and fluid sensitivity. Given the historical operator concerns over hydraulic fracturing in gas storage wells, plus the many other unique characteristics and resulting stimulation requirements of gas storage reservoirs (which are described later), the specific objective of this project was to identify new and novel fracture stimulation technologies that directly address these concerns and requirements, and to demonstrate/test their potential application in gas storage wells in various reservoir settings across the country. To compare these new methods to current industry deliverability enhancement norms in a consistent manner, their application was evaluated on a cost per unit of added deliverability basis, using typical non-fracturing well remediation methods as the benchmark and considering both short-term and long-term deliverability enhancement results. Based on the success (or lack thereof) of the various fracture stimulation technologies investigated, guidelines for their application, design and implementation have been developed. A final research objective was to effectively deploy the knowledge and experience gained from the project to the gas storage industry at-large.

  10. Recommendations for the shallow-crack fracture toughness testing task within the HSST (Heavy-Section Steel Technology) Program

    SciTech Connect (OSTI)

    Theiss, T.J. (Oak Ridge National Lab., TN (USA))

    1990-09-01

    Recommendations for Heavy-Section Steel Technology Program's investigation into the influence of crack depth on the fracture toughness of a steel prototypic of those in a reactor pressure vessel are included in this report. The motivation for this investigation lies in the fact that probabilistic fracture mechanics evaluations show that shallow flaws play a dominant role in the likelihood of vessel failure, and shallow-flaw specimens have exhibited an elevated toughness compared with conventional deep-notch fracture toughness specimens. Accordingly, the actual margin of safety of vessels may be greater than that predicted using existing deep-notch fracture-toughness results. The primary goal of the shallow-crack project is to investigate the influence of crack depth on fracture toughness under conditions prototypic of a reactor vessel. A limited data base of fracture toughness values will be assembled using a beam specimen of prototypic reactor vessel material and with a depth of 100 mm (4 in.). This will permit comparison of fracture-toughness data from deep-cracked and shallow-crack specimens, and this will be done for several test temperatures. Fracture-toughness data will be expressed in terms of the stress-intensity factor and crack-tip-opening displacement. Results of this investigation are expected to improve the understanding of shallow-flaw behavior in pressure vessels, thereby providing more realistic information for application to the pressurized-thermal shock issues. 33 refs., 17 figs.

  11. ADVANCED FRACTURING TECHNOLOGY FOR TIGHT GAS: AN EAST TEXAS FIELD DEMONSTRATION

    SciTech Connect (OSTI)

    Mukul M. Sharma

    2005-03-01

    The primary objective of this research was to improve completion and fracturing practices in gas reservoirs in marginal plays in the continental United States. The Bossier Play in East Texas, a very active tight gas play, was chosen as the site to develop and test the new strategies for completion and fracturing. Figure 1 provides a general location map for the Dowdy Ranch Field, where the wells involved in this study are located. The Bossier and other tight gas formations in the continental Unites States are marginal plays in that they become uneconomical at gas prices below $2.00 MCF. It was, therefore, imperative that completion and fracturing practices be optimized so that these gas wells remain economically attractive. The economic viability of this play is strongly dependent on the cost and effectiveness of the hydraulic fracturing used in its well completions. Water-fracs consisting of proppant pumped with un-gelled fluid is the type of stimulation used in many low permeability reservoirs in East Texas and throughout the United States. The use of low viscosity Newtonian fluids allows the creation of long narrow fractures in the reservoir, without the excessive height growth that is often seen with cross-linked fluids. These low viscosity fluids have poor proppant transport properties. Pressure transient tests run on several wells that have been water-fractured indicate a long effective fracture length with very low fracture conductivity even when large amounts of proppant are placed in the formation. A modification to the water-frac stimulation design was needed to transport proppant farther out into the fracture. This requires suspending the proppant until the fracture closes without generating excessive fracture height. A review of fracture diagnostic data collected from various wells in different areas (for conventional gel and water-fracs) suggests that effective propped lengths for the fracture treatments are sometimes significantly shorter than those predicted by fracture models. There was no accepted optimal method for conducting hydraulic fracturing in the Bossier. Each operator used a different approach. Anadarko, the most active operator in the play, had tested at least four different kinds of fracture treatments. The ability to arrive at an optimal fracturing program was constrained by the lack of adequate fracture models to simulate the fracturing treatment, and an inability to completely understand the results obtained in previous fracturing programs. This research aimed at a combined theoretical, experimental and field-testing program to improve fracturing practices in the Bossier and other tight gas plays.

  12. FRACTURE ENHANCED SOIL VAPOR EXTRACTION TECHNOLOGY DEMONSTRATION AT THE A-014 OUTFALL

    SciTech Connect (OSTI)

    Riha, B; Warren Hyde, W; Richard Hall , R

    2008-03-12

    Data collected during this study show that the performance of hydraulically fractured wells (with respect to mass removal rates) may tend to decrease with time following precipitation events. These effects are due to temporary increases in water saturation in the formation within the vicinity of the fractures, therefore, the wells should tend to rebound during subsequent dry periods. The data available for fractured well versus conventional well performance (with respect to flow rate versus vacuum pressure) are limited in this study. However, the data that we have to draw from suggest that, with the possible exception of a few extreme examples, hydraulically fractured wells tend to perform better than conventional wells during soil vapor extraction (SVE) operation at the A-14 Outfall. The pancake like geometry associated with hydraulic fractures also leads to a significant increase in zone of influence (ZOI), as compared to conventional wells. The increase in ZOI is due to the radially extending, horizontal, high-permeability conduit nature of the hydraulic fracture, however, air-flow into the fracture is predominately vertical (occurring at right angles to the fracture plane). Flow rates from above and below the fracture will tend to be equivalent when the formation is homogeneous, however, in the case of directionally fining depositional sequences flow rates will be greater from the direction of increasing permeability. The Upland Unit is a fining upward sequence, therefore flow rates (and contaminant mass flow rates) will tend to be higher below the fracture. This suggests that emplacing the fractures slightly above the source zone is an important strategy for accelerating contaminant removal at the A-014 Outfall site and in the Upland Unit at the SRS. However, due to the multitude of previous borings at the A-014 Outfall site, the shallower fractures failed. More than 2500 lbs of chlorinated volatile organic compounds (cVOCs) were removed during approximately 6 months of fractured well SVE operation at the A-014 field site. Plotting total mass removed over this time period shows a roughly linear relationship Figure 7. This occurs because the mass removal rate remains fairly constant with time. When mass removal comes predominately from cVOCs stored in the vapor phase there is a marked decline in mass removal rate over a short period of time due to the limiting nature of diffusion. Constant mass removal rates suggest that a source zone has been directly targeted and, therefore, is providing a constant supply of cVOC that partitions into the vapor phase and is removed through the well. Directly targeting and removing source zones is the most efficient approach to remediating contaminated sites. Results of this study show that utilization of hydraulic fractures during SVE is an effective approach for increasing remediation efficiency at the A-014 Outfall field site and in the Upland Unit at the SRS. Hydraulically fractured wells tend to produce greater flow rates and create larger ZOI's than do conventional wells. These attributes allow fractured wells to effectively treat larger volumes of formation. The unique sand-emplacement geometry associated with hydraulically fractured wells also allows direct targeting of multiple zones located at similar elevations within a fairly large radius of the well. The ability to directly target source zones significantly decreases diffusion pathways, therefore, significantly decreasing the time required to reach remediation goals.

  13. The FRAC Act: The Fracturing Responsibility and

    E-Print Network [OSTI]

    Smerdon, Jason E.

    ;4 Hydraulic fracturing, commonly referred to as hydrofracking or fracking, is a technology used to stimulate

  14. Fracture-Induced Anisotropic Attenuation

    E-Print Network [OSTI]

    2012-03-23

    (the lossless elastic limit) times one unit of time. The SH wave energy velocity is ..... Technology. Hood JA (1991) A simple method for decomposing fracture- ...

  15. 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...

  16. Numerical modeling of hydraulic fracture initiation and development

    E-Print Network [OSTI]

    2007-05-25

    Calculation scheme for modeling a hydraulic fracturing process: horizontal section of a ...... Jr., “Overview of current hydraulic fracturing design and treatment technology. .... A. A. Dobroskok, A. Ghassemi, and A. M. Linkov, “Extended structural ...

  17. Numerical Investigation of Interaction Between Hydraulic Fractures and Natural Fractures 

    E-Print Network [OSTI]

    Xue, Wenxu

    2011-02-22

    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...

  18. Introduction Fracture at small length scales is a concern

    E-Print Network [OSTI]

    Suo, Zhigang

    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

  19. Implementation of the Ensemble Kalman Filter in the Characterization of Hydraulic Fractures in Shale Gas Reservoirs by Integrating Downhole Temperature Sensing Technology 

    E-Print Network [OSTI]

    Moreno, Jose A

    2014-08-12

    Multi-stage hydraulic fracturing in horizontal wells has demonstrated successful results for developing unconventional low-permeability oil and gas reservoirs. Despite being vastly implemented by different operators across North America, hydraulic...

  20. Tracer Methods for Characterizing Fracture Creation in Enhanced...

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

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

  1. Tracer Methods for Characterizing Fracture Stimulation in Enhanced...

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

    Tracer Methods for Characterizing Fracture Stimulation in Enhanced Geothermal Systems (EGS); 2010 Geothermal Technology Program Peer Review Report Tracer Methods for Characterizing...

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

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

    & Publications Tracer Methods for Characterizing Fracture Stimulation in Enhanced Geothermal Systems (EGS); 2010 Geothermal Technology Program Peer Review Report Tracer Methods...

  3. Fracture Characterization in Enhanced Geothermal Systems by Wellbore...

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

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

  4. Fracture Properties From Seismic Scattering

    E-Print Network [OSTI]

    Burns, Daniel R.

    2007-01-01

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

  5. Discrete Fracture Reservoir Simulation

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

    Discrete Fracture Reservoir Simulation Shale Gas Flow Simulation Shale Gas Flow Simulation FRACGENNFFLOW, fractured reservoir modeling software developed by NETL's Geological and...

  6. A compendium of fracture flow models, 1994

    SciTech Connect (OSTI)

    Diodato, D.M.

    1994-11-01

    The report is designed to be used as a decision-making aid for individuals who need to simulate fluid flow in fractured porous media. Fracture flow codes of varying capability in the public and private domain were identified in a survey of government, academia, and industry. The selection and use of an appropriate code requires conceptualization of the geology, physics, and chemistry (for transport) of the fracture flow problem to be solved. Conceptual models that have been invoked to describe fluid flow in fractured porous media include explicit discrete fracture, dual continuum (porosity and/or permeability), discrete fracture network, multiple interacting continua, multipermeability/multiporosity, and single equivalent continuum. The explicit discrete-fracture model is a ``near-field`` representation, the single equivalent continuum model is a ``far-field`` representation, and the dual-continuum model is intermediate to those end members. Of these, the dual-continuum model is the most widely employed. The concept of multiple interacting continua has been applied in a limited number of examples. Multipermeability/multiporosity provides a unified conceptual model. The ability to accurately describe fracture flow phenomena will continue to improve as a result of advances in fracture flow research and computing technology. This improvement will result in enhanced capability to protect the public environment, safety, and health.

  7. Geomechanics of hydraulic fracturing microseismicity

    E-Print Network [OSTI]

    Ze'ev, Reches

    Geomechanics of hydraulic fracturing microseismicity: Part 1. Shear, hybrid, and tensile events of hydraulic- fracturing-induced microseismicity. Microseismic events are commonly used to discern stimulation patterns and hydraulic fracture evolution; however, techniques beyond fracture mapping are required

  8. Water management in hydraulic fracturing-a planning and decision optimization platform

    E-Print Network [OSTI]

    Mehta, Neha, S.M. Massachusetts Institute of Technology

    2014-01-01

    Recent developments in hydraulic fracturing technology have enabled cost-effective production of unconventional resources, particularly shale gas in the U.S. The process of hydraulic fracturing is water intensive, requiring ...

  9. Temperature Prediction Model for Horizontal Well with Multiple Fractures in Shale Reservoir 

    E-Print Network [OSTI]

    Yoshida, Nozomu

    2013-04-12

    Fracture diagnostics is a key technology for well performance prediction of a horizontal well in a shale reservoir. The combination of multiple fracture diagnostic techniques gives reliable results, and temperature data has potential to provide more...

  10. Modeling Performance of Horizontal Wells with Multiple Fractures in Tight Gas Reservoirs 

    E-Print Network [OSTI]

    Dong, Guangwei

    2011-02-22

    Multiple transverse fracturing along a horizontal well is a relatively new technology that is designed to increase well productivity by increasing the contact between the reservoir and the wellbore. For multiple transverse fractures, the performance...

  11. Candidate Well Selection for the Test of Degradable Biopolymer as Fracturing Fluid 

    E-Print Network [OSTI]

    Hwang, Yun Suk

    2012-02-14

    Hydraulic fracturing is a well-established technology of generating highly conductive flow path inside the rock by injecting massive amount of fracturing fluid and proppant with sufficient pressure to break the formation apart. But as the concern...

  12. Experimental Investigation of Propped Fracture Conductivity in Tight Gas Reservoirs Using The Dynamic Conductivity Test 

    E-Print Network [OSTI]

    Romero Lugo, Jose 1985-

    2012-10-24

    Hydraulic Fracturing stimulation technology is used to increase the amount of oil and gas produced from low permeability reservoirs. The primary objective of the process is to increase the conductivity of the reservoir by the creation of fractures...

  13. High velocity impact fracture

    E-Print Network [OSTI]

    Teng, Xiaoqing

    2005-01-01

    An in-depth understanding of dynamic ductile fracture is one of the most important steps to improve the survivability of critical structures such as the lost Twin Towers. In the present thesis, the macroscopic fracture ...

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

    E-Print Network [OSTI]

    Forbis, Robert E.

    2014-01-01

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

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

    E-Print Network [OSTI]

    Forbis, Robert E.

    2014-01-01

    History of Hydraulic Fracturing’s Expansion Across The WestHistory of Hydraulic Fracturing’s Expansion Across the Westuse of the hydraulic fracturing development process. First,

  16. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, Jeffrey R.; Glaser, Steven D.

    2008-01-01

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

  17. Simulation of Hydraulic Fractures and their Interactions with Natural Fractures 

    E-Print Network [OSTI]

    Sesetty, Varahanaresh

    2012-10-19

    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...

  18. Fracture characterization from attenuation of Stoneley waves across a fracture

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    2012-01-01

    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 ...

  19. Geothermal Ultrasonic Fracture Imager

    Broader source: Energy.gov [DOE]

    Development of a downhole wireline tool to characterize fractures in EGS wells in temperatures up to 300°C and depths up to 10; 000 m.

  20. MODE II FRACTURE BEHAVIOR OF BONDED VISCOELASTIC THERMAL COMPRESSED WOOD

    E-Print Network [OSTI]

    Nairn, John A.

    MODE II FRACTURE BEHAVIOR OF BONDED VISCOELASTIC THERMAL COMPRESSED WOOD Andreja Kutnar* Graduate Student Department of Wood Science and Technology Biotechnical Faculty University of Ljubljana 1000 Ljubljana, Slovenia Frederick A. Kamke Professor John A. Nairn Professor Department of Wood Science

  1. June 26, 2000 1 Fracture in Thin Films

    E-Print Network [OSTI]

    Suo, Zhigang

    in many technologies. Examples include zirconia coatings as thermal barriers on superalloys in enginesJune 26, 2000 1 Fracture in Thin Films Z. Suo Mechanical and Aerospace Engineering Department

  2. Diagnosis of Fracture Flow Conditions with Acoustic Sensing 

    E-Print Network [OSTI]

    Martinez, Roberto

    2014-07-10

    Distributed acoustic sensing (DAS) is an emerging technology in hydraulic fracture diagnosis. Current uses of DAS systems have been limited to qualitative analysis that pinpoint noise sources, such as injection into formation or production from a...

  3. Geomechanics of hydraulic fracturing microseismicity

    E-Print Network [OSTI]

    Ze'ev, Reches

    Geomechanics of hydraulic fracturing microseismicity: Part 2. Stress state determination Seth Busetti and Ze'ev Reches ABSTRACT We investigate the hydraulic fracturing process by analysis, stress shadowing adjacent to large parent hydraulic fractures, and crack tip stress perturbations. Data

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

    E-Print Network [OSTI]

    Lolon, Elyezer P.

    2006-04-12

    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...

  5. CX-012020: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Connectivity Between Fractures and Pores in Hydrocarbon-Rich Mudrocks CX(s) Applied: A9, B3.6 Date: 04/29/2014 Location(s): Texas Offices(s): National Energy Technology Laboratory

  6. CX-012493: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Geophysical and Mineralogical Controls on the Rheology of Fracture Slip… CX(s) Applied: B3.6Date: 41855 Location(s): PennsylvaniaOffices(s): National Energy Technology Laboratory

  7. CX-012497: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Geophysical and Mineralogical Controls on the Rheology of Fracture Slip... CX(s) Applied: B3.6Date: 41852 Location(s): New JerseyOffices(s): National Energy Technology Laboratory

  8. CX-012542: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Geomechanical Framework for CO2 Storage in Fractured Reservoirs and Caprocks for Sedimentary Basins CX(s) Applied: A1, A9Date: 41834 Location(s): OhioOffices(s): National Energy Technology Laboratory

  9. CX-007477: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    A Geomechanical Analysis of Gas Shale Fracturing and Its Containment CX(s) Applied: B3.6 Date: 12/09/2011 Location(s): Texas Offices(s): National Energy Technology Laboratory

  10. CX-007474: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    A Geomechanical Analysis of Gas Shale Fracturing and Its Containment CX(s) Applied: B3.6 Date: 12/13/2011 Location(s): Utah Offices(s): National Energy Technology Laboratory

  11. CX-012273: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Multiscale Modeling of Carbon Dioxide Migration and Trapping in Fractured Reservoirs with Validation CX(s) Applied: A1, A9 Date: 06/25/2014 Location(s): California Offices(s): National Energy Technology Laboratory

  12. CX-012274: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Multiscale Modeling of Carbon Dioxide Migration and Trapping in Fractured Reservoirs with Validation CX(s) Applied: A1, A9 Date: 06/25/2014 Location(s): United Kingdom Offices(s): National Energy Technology Laboratory

  13. CX-012272: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Multiscale Modeling of Carbon Dioxide Migration and Trapping in Fractured Reservoirs with Validation CX(s) Applied: A1, A8, A9 Date: 06/25/2014 Location(s): New Jersey Offices(s): National Energy Technology Laboratory

  14. Compartmentalization analysis using discrete fracture network models

    SciTech Connect (OSTI)

    La Pointe, P.R.; Eiben, T.; Dershowitz, W.; Wadleigh, E.

    1997-08-01

    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.

  15. Geothermal fracture stimulation technology. Volume III. Geothermal fracture fluids

    SciTech Connect (OSTI)

    Not Available

    1981-01-01

    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.

  16. Fracture mechanics: 26. volume

    SciTech Connect (OSTI)

    Reuter, W.G.; Underwood, J.H.; Newman, J.C. Jr.

    1995-12-31

    The original objective of these symposia was to promote technical interchange between researchers from the US and worldwide in the field of fracture. This objective was recently expanded to promote technical interchange between researchers in the field of fatigue and fracture. The symposium began with the Swedlow Memorial Lecture entitled ``Patterns and Perspectives in Applied Fracture Mechanics.`` The remaining 42 papers are divided into the following topical sections: Constraint crack initiation; Constraint crack growth; Weldments; Engineered materials; Subcritical crack growth; Dynamic loading; and Applications. Papers within the scope of the Energy Data Base have been processed separately.

  17. Technolog

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

    focuses on multi-scale, multiphysics approaches to understanding natural systems, "engineering the earth" with sensing and drilling technologies and characterizing geomaterials...

  18. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, J R; Glaser, Steven D

    2007-01-01

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

  19. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, Jeffrey R.; Glaser, Steven D.

    2008-01-01

    during hydraulic fracturing of Bunter sandstones, Proc. NearMonitoring during hydraulic fracturing using the TG-2 well,processes in hydraulic fracturing, Quarterly Report for The

  20. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, J R; Glaser, Steven D

    2007-01-01

    during hydraulic fracturing of Bunter sandstones, Proc. NearSP response during hydraulic fracturing. Citation: Moore, J.observations during hydraulic fracturing, J. Geophys. Res. ,

  1. International Journal of Fracture 119/120: 387405, 2003. 2003 Kluwer Academic Publishers. Printed in the Netherlands.

    E-Print Network [OSTI]

    Volinsky, Alex A.

    International Journal of Fracture 119/120: 387­405, 2003. © 2003 Kluwer Academic Publishers. Printed in the Netherlands. Length scales for the fracture of nanostructures WILLIAM W. GERBERICH1 , JOHN and fracture in emerging technologies. Recent analysis by two groups at the atomistic (Horstmeyer and Baskes

  2. Acid Fracture and Fracture Conductivity Study of Field Rock Samples 

    E-Print Network [OSTI]

    Underwood, Jarrod

    2013-11-15

    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...

  3. Investigation of Created Fracture Geometry through Hydraulic Fracture Treatment Analysis 

    E-Print Network [OSTI]

    Ahmed, Ibraheem 1987-

    2012-11-30

    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...

  4. Technologies

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired Solar Fuel ProductionRecoverable15/2008Technologies Technologies

  5. Technology

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired Solar FuelTechnology /newsroom/_assets/images/s-icon.png Technology

  6. Fracture Conductivity of the Eagle Ford Shale 

    E-Print Network [OSTI]

    Guzek, James J

    2014-07-25

    Hydraulic fracturing is a well completions technique that induces a network of flow channels in a reservoir. These channels are characterized by fracture conductivity, a measure of how easily a liquid or gas flows through the fracture. Fracture...

  7. Reservoir fracture characterizations from seismic scattered waves

    E-Print Network [OSTI]

    Fang, Xinding

    2012-01-01

    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 ...

  8. Fracture of Thermosetting Polymers: Experiments and Modeling 

    E-Print Network [OSTI]

    Benzerga, Amine; Burgess, Brad

    2011-08-04

    of a resin known as epoxy E862, which is a polymer resin currently explored by NASA researchers, and then model this behavior using FEM. In the early 1990's, successful computational methodologies for modeling fracture of metal-matrix composites... of Aerospace Engineering Aircraft are becoming extremely complex in the modern age. Fueled by the advent of new technology, a modern plane?s makeup and structure are changing considerably. Recently the idea to utilize a greater amount of composite...

  9. Fracture prediction in metal sheets

    E-Print Network [OSTI]

    Lee, Young-Woong

    2005-01-01

    One of the most important failure modes of thin-walled structures is fracture. Fracture is predominantly tensile in nature and, in most part, is operated by the physical mechanisms of void nucleation, growth, and linkage. ...

  10. Fluid Flow Modeling in Fractures

    E-Print Network [OSTI]

    Sarkar, Sudipta

    2004-01-01

    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, ...

  11. Fractured Petroleum Reservoirs

    SciTech Connect (OSTI)

    Firoozabadi, Dr. Abbas

    2000-01-18

    In this report the results of experiments of water injection in fractured porous media comprising a number of water-wet matrix blocks are reported for the first time. The blocks experience an advancing fracture-water level (FWL). Immersion-type experiments are performed for comparison; the dominant recovery mechanism changed from co-current to counter-current imbibition when the boundary conditions changed from advancing FWL to immersion-type. Single block experiments of co-current and counter-current imbibition was performed and co-current imbibition leads to more efficient recovery was found.

  12. Subsurface fracture mapping from geothermal wellbores. Final report

    SciTech Connect (OSTI)

    Hartenbaum, B.A.; Rawson, G.

    1983-08-01

    To advance the state-of-the-art in Hot Dry Rock technology, and evaluation is made of (1) the use of both electromagnetic and acoustic radar to map far-field fractures, (2) the use of more than twenty different conventional well logging tools to map borehole-fracture intercepts, (3) the use of magnetic dipole ranging to determine the relative positions of the injection well and the production well within the fractured zone, (4) the use of passive microseismic methods to determine the orientation and extent of hydraulic fractures, and (5) the application of signal processing techniques to fracture mapping including tomography, holography, synthetic aperture, image reconstruction, and the relative importance of phase and amplitude information. It is found that according to calculations, VHF backscatter radar has the potential for mapping fractures within a distance of 50 +- 20 meters from the wellbore. A new technique for improving fracture identification is presented. The range of acoustic radar is five to seven times greater than that of VHF radar when compared on the basis of equal resolution, i.e., equal wavelengths. Analyses of extant data indicate that when used synergistically the (1) caliper, (2) resistivity dipmeter, (3) televiewer, (4) television, (5) impression packer, and (6) acoustic transmission are useful for mapping borehole-fracture intercepts. A new model of hydraulic fracturing is presented which indicates that a hydraulic fracture is dynamically unstable; consequently, improvements in locating the crack tip may be possible. The importance of phase in signal processing is stressed and those techniques which employ phase data are emphasized for field use.

  13. Fracture Mechanics and Failure Analysis

    E-Print Network [OSTI]

    New South Wales, University of

    concepts: Griffith criterion, K=Ya, K=KIC, ductile and brittle fracture, cyclic fatigue, environmentally, yield criteria. 4 Elastic-Plastic Analysis 5 Fracture toughness testing 6 Crack Growth Resistance - RMATS4004 Fracture Mechanics and Failure Analysis Course Outline Session 1, 2015 School of Materials

  14. Infiltration into Fractured Bedrock

    SciTech Connect (OSTI)

    Salve, Rohit; Ghezzehei, Teamrat A.; Jones, Robert

    2007-09-01

    One potential consequence of global climate change and rapid changes in land use is an increased risk of flooding. Proper understanding of floodwater infiltration thus becomes a crucial component of our preparedness to meet the environmental challenges of projected climate change. In this paper, we present the results of a long-term infiltration experiment performed on fractured ash flow tuff. Water was released from a 3 x 4 m{sup 2} infiltration plot (divided into 12 square subplots) with a head of {approx}0.04 m, over a period of {approx}800 days. This experiment revealed peculiar infiltration patterns not amenable to current infiltration models, which were originally developed for infiltration into soils over a short duration. In particular, we observed that in part of the infiltration plot, the infiltration rate abruptly increased a few weeks into the infiltration tests. We suggest that these anomalies result from increases in fracture permeability during infiltration, which may be caused by swelling of clay fillings and/or erosion of infill debris. Interaction of the infiltration water with subsurface natural cavities (lithophysal cavities) could also contribute to such anomalies. This paper provides a conceptual model that partly describes the observed infiltration patterns in fractured rock and highlights some of the pitfalls associated with direct extension of soil infiltration models to fractured rock over a long period.

  15. Technologies

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With U.S. CoalMexico IndependentMatter and Technologies R&D

  16. Microearthquake Technology for EGS Fracture Characterization...

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

    Engineered Geothermal System through Hydraulic and Thermal Stimulation Integration of Noise and Coda Correlation Data into Kinematic and Waveform Inversions Newberry EGS...

  17. Fracture Characterization Technologies | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainable Urban TransportFortistar LLC Jump

  18. Hydraulic Fracturing Technology | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPLforLDRD Report11,SecurityHome solarEnergyHugh Chen -Energytaken from

  19. Microearthquake Technology for EGS Fracture Characterization

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURING OFFICESpecial ReportProposal toDepartment ofEnergy Michigan3Sheet, 2014

  20. Microearthquake Technology for EGS Fracture Characterization; 2010

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURING OFFICESpecial ReportProposal toDepartment ofEnergy Michigan3Sheet,

  1. Microearthquake Technology for EGS Fracture Characterization | Department

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i nAand DOE Safetyof Methane Hydrate Program AnnualEnergy PhotoSheet, 2014

  2. INTERPRETATION OF A HYDRAULIC FRACTURING EXPERIMENT, MONTICELLO, SOUTH CAROLINA

    E-Print Network [OSTI]

    Narasimhan, T.N.

    2014-01-01

    OF A HYDRAULIC FRACTURING EXPERIMENT, MONTICELLO, SOUTHOF A HYDRAULIC FRACTURING EXPERIMENT, MONTICELLO, SOUTHdata from a hydraulic fracturing experiment have been

  3. Hydrogen-Assisted Fracture: Materials Testing and Variables Governing...

    Office of Environmental Management (EM)

    Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture SNL has 40+ years...

  4. Phase Field Fracture Mechanics.

    SciTech Connect (OSTI)

    Robertson, Brett Anthony

    2015-11-01

    For this assignment, a newer technique of fracture mechanics using a phase field approach, will be examined and compared with experimental data for a bend test and a tension test. The software being used is Sierra Solid Mechanics, an implicit/explicit finite element code developed at Sandia National Labs in Albuquerque, New Mexico. The bend test experimental data was also obtained at Sandia Labs while the tension test data was found in a report online from Purdue University.

  5. Procedure for estimating fracture energy from fracture surface roughness

    DOE Patents [OSTI]

    Williford, Ralph E. (Kennewick, WA)

    1989-01-01

    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.

  6. Brittle Fracture Ductile to Brittle transition

    E-Print Network [OSTI]

    Subramaniam, Anandh

    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

  7. FRACTURED PETROLEUM RESERVOIRS

    SciTech Connect (OSTI)

    Abbas Firoozabadi

    1999-06-11

    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.

  8. Simulation of naturally fractured reservoirs

    SciTech Connect (OSTI)

    Saidi, A.M.

    1983-11-01

    A three-dimensional, three-phase reservoir simulator was developed to study the behavior of fully or partially fractured reservoirs. It is also demonstrated, that when a fractured reservoir is subject to a relatively large rate of pressure drop and/or it composed of relatively large blocks, the pseudo steady-state pressure concept gives large errors as compared with transient fromulation. In addition, when gravity drainage and imbibitum processes, which is the most important mechanism in the fractured reservoirs, are represented by a ''lumped parameter'' even larger errors can be produced in exchange flow between matrix and fractures. For these reasons, the matrix blocks are gridded and the transfer between matrix and fractures are calculated using pressure and diffusion transient concept. In this way the gravity drainage is also calculated accurately. As the matrix-fracture exchange flow depends on the location of each matrix grid relative to the GOC and/or WOC in fracture, the exchange flow equation are derived and given for each possible case. The differential equation describing the flow of water, oil, and gas within the matrix and fracture system, each of which may contain six unknowns, are presented. The two sets of equations are solved implicitly for pressure water, and gas stauration in both matrix and fractures. The first twenty two years of the history of Haft Kel field was successfully matched with this model and the results are included.

  9. Seismic anisotropy of fractured rock

    E-Print Network [OSTI]

    M. Schoenberg, C. M. Sayers

    2000-02-18

    anisotropic media: Pure Appl. Geophys., 58, 53-112. Henyey ... simulated fractured medium: Geophysics, 58, 964-977. Hudson ... ASCE, 106, 1039-1051. 1992 ...

  10. Automated Optimization Strategies for Horizontal Wellbore and Hydraulic Fracture Stages Placement in Unconventional Gas Reseroirs 

    E-Print Network [OSTI]

    Plaksina, Tatyana

    2015-05-05

    In the last decades rapid advances in horizontal drilling and hydraulic fracturing technologies ensure production of commercial quantities of natural gas from many unconventional reservoirs. Reservoir management and development strategies for shale...

  11. Interferometric hydrofracture microseism localization using neighboring fracture

    E-Print Network [OSTI]

    Poliannikov, Oleg V.

    2011-05-19

    Hydraulic fracturing is the process of injecting high-pressure fluids into a reservoir to induce fractures and thus improve reservoir productivity. Microseismic event localization is used to locate created fractures. ...

  12. Fracture compliance estimation using borehole tube waves

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    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 ...

  13. On the fracture toughness of advanced materials

    E-Print Network [OSTI]

    Launey, Maximilien E.

    2009-01-01

    higher intrinsic toughness For ductile fracture, conversely,of fracture resistance and toughness. In ductile materialsductile, i.e. , microvoid coalescence, fracture, which is locally strain-controlled and generally results in much higher toughness.

  14. Interferometric hydrofracture microseism localization using neighboring fracture

    E-Print Network [OSTI]

    Poliannikov, Oleg V.

    Hydraulic fracturing is the process of injecting high-pressure fluids into a reservoir to induce fractures and thus improve reservoir productivity. Microseismic event localization is used to locate created fractures. ...

  15. Discrete Fracture Reservoir Simulation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalentLaboratory | National NuclearDiscoveringDiscrete Fracture Reservoir

  16. Wave Propagation in Fractured Poroelastic Media

    E-Print Network [OSTI]

    robiel

    instance, tectonic stresses and natural or artificial hydraulic fracturing caused ... Seismic wave propagation through fractures and cracks is an important subject ...

  17. EVALUATION OF ENHANCED VOC REMOVAL WITH SOIL FRACTURING IN THE SRS UPLAND UNIT

    SciTech Connect (OSTI)

    Riha, B

    2005-10-31

    The Environmental Restoration Technology Section (ERTS) of the Savannah River National Laboratory (SRNL) conducted pilot scale testing to evaluate the effectiveness of using hydraulic fracturing as a means to improve soil vapor extraction (SVE) system performance. Laboratory and field research has shown that significant amounts of solvents can be entrapped in low permeability zones by capillary forces and removal by SVE can be severely limited due to low flow rates, mass transfer resistance of the hydrophobic compounds by trapped interparticle water, and diffusion resistance. Introducing sand-filled fractures into these tight zones improves the performance of SVE by (1) increasing the overall permeability of the formation and thereby increasing SVE flow rates, (2) shortening diffusion pathways, and (3) increasing air permeability by improving pore water removal. The synergistic effect of the fracture well completion methods, fracture and flow geometry, and pore water removal appears to increase the rate of solvent mass removal over that of increasing flow rate alone. A field test was conducted where a conventional well in the SRS Upland Unit was tested before and after hydraulic fracturing. ERTS teamed with Clemson University through the South Carolina University and Education Foundation (SCUREF) program utilizing their expertise in fracturing and fracture modeling. The goals of the fracturing pilot testing were to evaluate the following: (1) The effect of hydraulic fractures on the performance of a conventional well. This was the most reliable way to remove the effects of spatial variations in permeability and contaminant distribution on relative well performance. It also provided data on the option of improving the performance of existing wells using hydraulic fractures. (2) The relative performance of a conventional SVE well and isolated hydraulic fractures. This was the most reliable indicator of the performance of hydraulic fractures that could be created in a full-scale implementation. The SVE well, monitoring point arrays and four fracturing wells were installed and the well testing has been completed. Four fractures were successfully created the week of July 25, 2005. The fractures were created in an open area at the bottom of steel well casing by using a water jet to create a notch in the soil and then injecting a guar-sand slurry into the formation. The sand-filled fractures increase the effective air permeability of the subsurface formation diffusion path lengths for contaminant removal. The primary metrics for evaluation were an increase in SVE flow rates in the zone of contamination and an increase in the zone of influence. Sufficient testing has been performed to show that fracturing in the Upland Unit accelerates SVE solvent remediation and fracturing can increase flow rates in the Upland Unit by at least one order of magnitude.

  18. Horizontal well replaces hydraulic fracturing in North Sea gas well

    SciTech Connect (OSTI)

    Reynolds, D.A.; Seymour, K.P. )

    1991-11-25

    This paper reports on excessive water production from hydraulically fractured wells in a poor quality reservoir in the North SEa which prompted the drilling of a horizontal well. Gas production from the horizontal well reached six times that of the offset vertical wells, and no water production occurred. This horizontal well proved commercial the western section of the Anglia field. Horizontal drilling in the North SEa is as an effective technology to enhance hydrocarbon recovery from reservoirs that previously had proven uncommercial with other standard techniques. It is viable for the development of marginal reservoirs, particularly where conditions preclude stimulation from hydraulic fracturing.

  19. Anthony V. Cugini Director, National Energy Technology Laboratory

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

    to be the result of the combined application of horizontal drilling and large-volume hydraulic fracturing technologies. EIA's 2012 Annual Energy Outlook estimates that 482...

  20. TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES...

    Open Energy Info (EERE)

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

  1. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, Jeffrey R.; Glaser, Steven D.

    2008-01-01

    assumption that fluid flow is laminar; an assumption thatspecimens, fluid flow prior to fracturing remains laminar

  2. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, J R; Glaser, Steven D

    2007-01-01

    assumption that fluid flow is laminar; an assumption thatspecimens, fluid flow prior to fracturing remains laminar

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

    E-Print Network [OSTI]

    Ritchie, Robert

    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

  4. FRACTURE STIMULATION IN ENHANCED GEOTHERMAL

    E-Print Network [OSTI]

    Stanford University

    FRACTURE STIMULATION IN ENHANCED GEOTHERMAL SYSTEMS A REPORT SUBMITTED TO THE DEPARTMENT OF ENERGY (Principal Advisor) #12;#12;v Abstract Enhanced Geothermal Systems (EGS) are geothermal reservoirs formed

  5. Fracture of aluminum naval structures

    E-Print Network [OSTI]

    Galanis, Konstantinos, 1970-

    2007-01-01

    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. ...

  6. Sensitivity analysis of fracture scattering

    E-Print Network [OSTI]

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

    2010-01-01

    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, ...

  7. Capillary fracture of soft gels

    E-Print Network [OSTI]

    Joshua B. Bostwick; Karen E. Daniels

    2013-10-16

    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 important factor in the fracture process, as it can help mitigate large surface tractions; this finding is confirmed with experiments. We then develop a model for crack propagation by considering the transport of an inviscid fluid into the fracture tip of an incompressible material, and find that a simple energy-conservation argument can explain the observed material-independent power law. We compare predictions for both linear elastic and neo-Hookean solids finding that the latter better explains the observed exponent.

  8. Evaluating GPR polarization effects for imaging fracture channeling and estimating fracture properties

    E-Print Network [OSTI]

    Perll, Chris

    2013-12-31

    . To understand how the polarization of radar waves affects imaging of channelized flow in a horizontal fracture, i) a series of numerical forward models was created with varying fracture aperture, channel orientation, and varying fracture water electrical...

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

    E-Print Network [OSTI]

    Ogbechie, Joachim Nwabunwanne

    2012-02-14

    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...

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

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    2011-01-01

    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 ...

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

    E-Print Network [OSTI]

    Zhang, Yang

    2005-01-01

    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 ...

  12. DEVELOPMENT OF RESERVOIR CHARACTERIZATION TECHNIQUES AND PRODUCTION MODELS FOR EXPLOITING NATURALLY FRACTURED RESERVOIRS

    SciTech Connect (OSTI)

    Michael L. Wiggins; Raymon L. Brown; Faruk Civan; Richard G. Hughes

    2002-12-31

    For many years, geoscientists and engineers have undertaken research to characterize naturally fractured reservoirs. Geoscientists have focused on understanding the process of fracturing and the subsequent measurement and description of fracture characteristics. Engineers have concentrated on the fluid flow behavior in the fracture-porous media system and the development of models to predict the hydrocarbon production from these complex systems. This research attempts to integrate these two complementary views to develop a quantitative reservoir characterization methodology and flow performance model for naturally fractured reservoirs. The research has focused on estimating naturally fractured reservoir properties from seismic data, predicting fracture characteristics from well logs, and developing a naturally fractured reservoir simulator. It is important to develop techniques that can be applied to estimate the important parameters in predicting the performance of naturally fractured reservoirs. This project proposes a method to relate seismic properties to the elastic compliance and permeability of the reservoir based upon a sugar cube model. In addition, methods are presented to use conventional well logs to estimate localized fracture information for reservoir characterization purposes. The ability to estimate fracture information from conventional well logs is very important in older wells where data are often limited. Finally, a desktop naturally fractured reservoir simulator has been developed for the purpose of predicting the performance of these complex reservoirs. The simulator incorporates vertical and horizontal wellbore models, methods to handle matrix to fracture fluid transfer, and fracture permeability tensors. This research project has developed methods to characterize and study the performance of naturally fractured reservoirs that integrate geoscience and engineering data. This is an important step in developing exploitation strategies for optimizing the recovery from naturally fractured reservoir systems. The next logical extension of this work is to apply the proposed methods to an actual field case study to provide information for verification and modification of the techniques and simulator. This report provides the details of the proposed techniques and summarizes the activities undertaken during the course of this project. Technology transfer activities were highlighted by a two-day technical conference held in Oklahoma City in June 2002. This conference attracted over 90 participants and included the presentation of seventeen technical papers from researchers throughout the United States.

  13. Fracture induced anisotropy in viscoelastic UNLP, 11 Octubre de 2012

    E-Print Network [OSTI]

    Santos, Juan

    of earthquakes, and hydrocarbon and geothermal reservoirs are mainly composed of fractured rocks. Fracture: horizontal and vertical coordinates, respectively. When a dense set of parallel fractures is present

  14. INTERPRETATION OF A HYDRAULIC FRACTURING EXPERIMENT, MONTICELLO, SOUTH CAROLINA

    E-Print Network [OSTI]

    Narasimhan, T.N.

    2014-01-01

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

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

    E-Print Network [OSTI]

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

    2000-01-01

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

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

    E-Print Network [OSTI]

    Kim, Tae Hyung

    2009-05-15

    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...

  17. Evaluation and Effect of Fracturing Fluids on Fracture Conductivity in Tight Gas Reservoirs Using Dynamic Fracture Conductivity Test 

    E-Print Network [OSTI]

    Correa Castro, Juan

    2011-08-08

    concentrations under reservoirs conditions. The result of this study provides the basis to optimize the fracturing fluids and the polymer loading at different reservoir conditions, which may result in a clean and conductive fracture. Success in improving...

  18. Method for directional hydraulic fracturing

    DOE Patents [OSTI]

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

    1994-01-01

    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.

  19. GMINC - A MESH GENERATOR FOR FLOW SIMULATIONS IN FRACTURED RESERVOIRS

    E-Print Network [OSTI]

    Pruess, K.

    2010-01-01

    the Production of Superheated Steam from Fractured, Vapor-THE PRODUCTION OF SUPERHEATED STEAM FROM FRACTURED, VAPOR-

  20. Harmonic experiments to model fracture induced anisotropy

    E-Print Network [OSTI]

    Santos, Juan

    of earthquakes, and hydrocarbon and geothermal reservoirs are mainly composed of fractured rocks. Harmonic and vertical coordinates, respectively. When a dense set of parallel fractures is present, the medium behaves

  1. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, Jeffrey R.; Glaser, Steven D.

    2008-01-01

    during hydraulic fracturing Moore and Glaser, in press JGR,press JGR, B – 2006JB004373 where m is the average hydraulichydraulic fracturing with water. Moore and Glaser, in press

  2. Modeling of Acid Fracturing in Carbonate Reservoirs 

    E-Print Network [OSTI]

    Al Jawad, Murtada s

    2014-06-05

    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...

  3. Lisburne Formation fracture characterization and flow modeling 

    E-Print Network [OSTI]

    Karpov, Alexandre Valerievich

    2001-01-01

    Evaluation of fractured reservoirs for fluid flow and optimal well placement is often very complicated. In general, fractures enhance permeability and increase access to matrix surface, but their random aspects create difficulties for analysis...

  4. Acoustic Character Of Hydraulic Fractures In Granite

    E-Print Network [OSTI]

    Paillet, Frederick I.

    1983-01-01

    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 ...

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

    E-Print Network [OSTI]

    Lu, Zhiming

    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

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

    E-Print Network [OSTI]

    Grujicic, Mica

    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

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

    E-Print Network [OSTI]

    Ritchie, Robert

    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

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

    E-Print Network [OSTI]

    Espinosa, Horacio D.

    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

  9. Testing Novel CR-39 Detector Deployment System For Identification of Subsurface Fractures, Soda Springs, ID

    SciTech Connect (OSTI)

    McLing, Travis; Carpenter, Michael; Brandon, William; Zavala, Bernie

    2015-06-01

    The Environmental Protection Agency (EPA) has teamed with Battelle Energy Alliance, LLC (BEA) at Idaho National Laboratory (INL) to facilitate further testing of geologic-fracture-identification methodology at a field site near the Monsanto Superfund Site located in Soda Springs, Idaho. INL has the necessary testing and technological expertise to perform this work. Battelle Memorial Institute (BMI) has engaged INL to perform this work through a Work for Others (WFO) Agreement. This study continues a multi-year collaborative effort between INL and EPA to test the efficacy of using field deployed Cr-39 radon in soil portals. This research enables identification of active fractures capable of transporting contaminants at sites where fractures are suspected pathways into the subsurface. Current state of the art methods for mapping fracture networks are exceedingly expensive and notoriously inaccurate. The proposed WFO will evaluate the applicability of using cheap, readily available, passive radon detectors to identify conductive geologic structures (i.e. fractures, and fracture networks) in the subsurface that control the transport of contaminants at fracture-dominated sites. The proposed WFO utilizes proven off-the-shelf technology in the form of CR-39 radon detectors, which have been widely deployed to detect radon levels in homes and businesses. In an existing collaborative EPA/INL study outside of this workscope,. CR-39 detectors are being utilized to determine the location of active transport fractures in a fractured granitic upland adjacent to a landfill site at the Fort Devens, MA that EPA-designated as National Priorities List (NPL) site. The innovative concept of using an easily deployed port that allows the CR-39 to measure the Rn-222 in the soil or alluvium above the fractured rock, while restricting atmospheric Rn-222 and soil sourced Ra from contaminating the detector is unique to INL and EPA approach previously developed. By deploying a series of these inexpensive detector-casing combinations statistical samples of the Rn-222 flux can be measured, elucidating the most communicative fractures (i.e. fractures that are actively transporting water and gasses). The Rn-222 measurements can then be used as an input to create a more accurate conceptual model to be used for transport modeling and related cleanup activities. If the team’s approach is demonstrated to be applicable to a wide variety of rock types and soil conditions it might potentially offer significant cost saving without a reduction in data quality at Monsanto Superfund and other sites underlain by fracture-dominated bedrock.

  10. Regulation of Hydraulic Fracturing in California

    E-Print Network [OSTI]

    Kammen, Daniel M.

    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

  11. Hydraulic Fracture: multiscale processes and moving

    E-Print Network [OSTI]

    Peirce, Anthony

    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

  12. Identifying Best Practices in Hydraulic Fracturing Using

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    Identifying Best Practices in Hydraulic Fracturing Using Virtual Intelligence Techniques SPE 72385 Results & Discussion Conclusion #12;SPE 72385 OBJECTIVE To identify Best Practices in Hydraulic Fracturing, are fractured upon completion to provide economic amounts of gas. #12;SPE 72385 BACKGROUND A dataset

  13. Hydraulic Fracture: multiscale processes and moving

    E-Print Network [OSTI]

    Peirce, Anthony

    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

  14. FRACTURE TOUGHNESS OF WOOD AND WOOD COMPOSITES

    E-Print Network [OSTI]

    Nairn, John A.

    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

  15. Models for MetaVCeramic Interface Fracture

    E-Print Network [OSTI]

    Suo, Zhigang

    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

  16. FRACTURE IN DISORDERED BRITTLE MEDIA A Dissertation

    E-Print Network [OSTI]

    Sethna, James P.

    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

  17. Presented by Statistical Physics of Fracture

    E-Print Network [OSTI]

    Presented by Statistical Physics of Fracture: Recent Advances through High-Performance Computing) ­ Phys. Rev. E 71 (2005a, 2005b, 2005c); 73 (2006a, 2006b) ­ Adv. Phys. (2006); Int. J. Fracture (2006); Int. J. Fracture (2008a, 2008b) ­ J. Phys. D (2009); J. Chem. Phys. (2009); Phys. Rev. B (2009

  18. Image-Guided Fracture David Mould

    E-Print Network [OSTI]

    Mould, David

    Image-Guided Fracture David Mould Department of Computer Science University of Saskatchewan Abstract We present an image filter that transforms an input line drawing into an image of a fractured of an uncracked texture. Key words: Non-photorealistic rendering, fracture, tex- ture synthesis 1 Introduction Non

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

    SciTech Connect (OSTI)

    R. L. Billingsley; V. Kuuskraa

    2006-03-31

    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.

  20. Sensitivity analysis of fracture scattering

    E-Print Network [OSTI]

    Fang, Xinding

    We use 2D and 3D finite-difference modeling to numerically calculate the seismic response of a single finite fracture with a linear-slip boundary in a homogeneous elastic medium. We use a point explosive source and ignore ...

  1. Geomechanical Simulation of Fluid-Driven Fractures

    SciTech Connect (OSTI)

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

    2012-11-30

    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.

  2. Predicting Fracture Energies and Crack-Tip Fields of Soft Tough Materials

    E-Print Network [OSTI]

    Teng Zhang; Shaoting Lin; Hyunwoo Yuk; Xuanhe Zhao

    2015-06-13

    Soft materials including elastomers and gels are pervasive in biological systems and technological applications. Whereas it is known that intrinsic fracture energies of soft materials are relatively low, how the intrinsic fracture energy cooperates with mechanical dissipation in process zone to give high fracture toughness of soft materials is not well understood. In addition, it is still challenging to predict fracture energies and crack-tip strain fields of soft tough materials. Here, we report a scaling theory that accounts for synergistic effects of intrinsic fracture energies and dissipation on the toughening of soft materials. We then develop a coupled cohesive-zone and Mullins-effect model capable of quantitatively predicting fracture energies of soft tough materials and strain fields around crack tips in soft materials under large deformation. The theory and model are quantitatively validated by experiments on fracture of soft tough materials under large deformations. We further provide a general toughening diagram that can guide the design of new soft tough materials.

  3. RESEARCH PROGRAM ON FRACTURED PETROLEUM RESERVOIRS

    SciTech Connect (OSTI)

    Abbas Firoozabadi

    2002-04-12

    Numerical simulation of water injection in discrete fractured media with capillary pressure is a challenge. Dual-porosity models in view of their strength and simplicity can be mainly used for sugar-cube representation of fractured media. In such a representation, the transfer function between the fracture and the matrix block can be readily calculated for water-wet media. For a mixed-wet system, the evaluation of the transfer function becomes complicated due to the effect of gravity. In this work, they use a discrete-fracture model in which the fractures are discretized as one dimensional entities to account for fracture thickness by an integral form of the flow equations. This simple step greatly improves the numerical solution. Then the discrete-fracture model is implemented using a Galerkin finite element method. The robustness and the accuracy of the approach are shown through several examples. First they consider a single fracture in a rock matrix and compare the results of the discrete-fracture model with a single-porosity model. Then, they use the discrete-fracture model in more complex configurations. Numerical simulations are carried out in water-wet media as well as in mixed-wet media to study the effect of matrix and fracture capillary pressures.

  4. Fracture-permeability behavior of shale

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

    Carey, J. William; Lei, Zhou; Rougier, Esteban; Mori, Hiroko; Viswanathan, Hari

    2015-05-08

    The fracture-permeability behavior of Utica shale, an important play for shale gas and oil, was investigated using a triaxial coreflood device and X-ray tomography in combination with finite-discrete element modeling (FDEM). Fractures generated in both compression and in a direct-shear configuration allowed permeability to be measured across the faces of cylindrical core. Shale with bedding planes perpendicular to direct-shear loading developed complex fracture networks and peak permeability of 30 mD that fell to 5 mD under hydrostatic conditions. Shale with bedding planes parallel to shear loading developed simple fractures with peak permeability as high as 900 mD. In addition tomore »the large anisotropy in fracture permeability, the amount of deformation required to initiate fractures was greater for perpendicular layering (about 1% versus 0.4%), and in both cases activation of existing fractures are more likely sources of permeability in shale gas plays or damaged caprock in CO? sequestration because of the significant deformation required to form new fracture networks. FDEM numerical simulations were able to replicate the main features of the fracturing processes while showing the importance of fluid penetration into fractures as well as layering in determining fracture patterns.« less

  5. Fracture-permeability behavior of shale

    SciTech Connect (OSTI)

    Carey, J. William; Lei, Zhou; Rougier, Esteban; Mori, Hiroko; Viswanathan, Hari

    2015-05-08

    The fracture-permeability behavior of Utica shale, an important play for shale gas and oil, was investigated using a triaxial coreflood device and X-ray tomography in combination with finite-discrete element modeling (FDEM). Fractures generated in both compression and in a direct-shear configuration allowed permeability to be measured across the faces of cylindrical core. Shale with bedding planes perpendicular to direct-shear loading developed complex fracture networks and peak permeability of 30 mD that fell to 5 mD under hydrostatic conditions. Shale with bedding planes parallel to shear loading developed simple fractures with peak permeability as high as 900 mD. In addition to the large anisotropy in fracture permeability, the amount of deformation required to initiate fractures was greater for perpendicular layering (about 1% versus 0.4%), and in both cases activation of existing fractures are more likely sources of permeability in shale gas plays or damaged caprock in CO? sequestration because of the significant deformation required to form new fracture networks. FDEM numerical simulations were able to replicate the main features of the fracturing processes while showing the importance of fluid penetration into fractures as well as layering in determining fracture patterns.

  6. Interaction between Injection Points during Hydraulic Fracturing

    E-Print Network [OSTI]

    Hals, Kjetil M D

    2012-01-01

    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.

  7. CX-100032: Categorical Exclusion Determination

    Office of Energy Efficiency and Renewable Energy (EERE)

    Seismic Analysis of Spatio-Temporal Fracture Generation During EGS Resource Development CX(s) Applied: A9 Date: 09/04/2014 Location(s): California Offices(s): Golden Field Office Technology Office: Geothermal Technologies Award Number: DE-EE0006766

  8. Permeability Calculation in a Fracture Network - 12197

    SciTech Connect (OSTI)

    Lee, Cheo Kyung; Kim, Hyo Won [Handong Global University, 3 Namsong-ri, Heunghae-eub, Buk-gu, Pohang, Kyungbuk, 791-708 (Korea, Republic of); Yim, Sung Paal [Korea Atomic Energy Research Institute, Yusong, Daejon, 305-600 (Korea, Republic of)

    2012-07-01

    Laminar flow of a viscous fluid in the pore space of a saturated fractured rock medium is considered to calculate the effective permeability of the medium. The effective permeability is determined from the flow field which is calculated numerically by using the finite element method. The computation of permeability components is carried out with a few different discretizations for a number of fracture arrangements. Various features such as flow field in the fracture channels, the convergence of permeability, and the variation of permeability among different fracture networks are discussed. The longitudinal permeability in general appears greater than the transverse ones. The former shows minor variations with fracture arrangement whereas the latter appears to be more sensitive to the arrangement. From the calculations of the permeability in a rock medium with a fracture network (two parallel fractures aligned in the direction of 45-deg counterclockwise from the horizontal and two connecting fractures(narrowing, parallel and widening) the following conclusions are drawn. 1. The permeability of fractured medium not only depends on the primary orientation of the main fractures but also is noticeably influenced by the connecting fractures in the medium. 2. The transverse permeability (the permeability in the direction normal to the direction of the externally imposed macro-scale pressure gradient) is only a fraction of the longitudinal one, but is sensitive to the arrangement of the connecting fractures. 3. It is important to figure out the pattern of the fractures that connect (or cross) the main fractures for reliable calculation of the transverse permeability. (authors)

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

    E-Print Network [OSTI]

    Wang, J.S.Y.

    2013-01-01

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

  10. Laboratory Study to Identify the Impact of Fracture Design Parameters over the Final Fracture Conductivity Using the Dynamic Fracture Conductivity Test Procedure 

    E-Print Network [OSTI]

    Pieve La Rosa, Andres Eduardo

    2011-08-08

    such as closure stress, and temperature and fracture fluid parameters such as proppant loading over the final conductivity of a hydraulic fracture treatment. With the purpose of estimating the relation between fracture conductivity and the design parameters, two...

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

    E-Print Network [OSTI]

    Nelson, J.T.

    2009-01-01

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

  12. This is the pre-peer reviewed version of the following article: "Can hydraulic fracturing make Poland self-sufficient in natural gas?", which will be published in final form in a

    E-Print Network [OSTI]

    Patzek, Tadeusz W.

    The International Energy Agency (IEA) has highlighted hydraulic fracturing (fracking) as the key to a "Golden Age in the future. In order to improve energy security in the EU, hydraulic fracturing or "fracking," as it commonly of Energy Technology on Shale Gas Technology. http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)2194

  13. A Resolution of the First Unitarian Universalist Society of Albany to Oppose the Current Practice of Hydraulic Fracturing and Support the

    E-Print Network [OSTI]

    Bystroff, Chris

    health and environmental adverse impacts of fracking, there is neither sufficient incentive to industry of Hydraulic Fracturing and Support the Widespread Adoption of Renewable Energy I. Whereas horizontal high-volume hydraulic fracturing ("fracking") is a recently- developed technology for extracting methane gas from shale

  14. Apparatus and method for monitoring underground fracturing

    DOE Patents [OSTI]

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

    1999-08-10

    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.

  15. Apparatus and method for monitoring underground fracturing

    DOE Patents [OSTI]

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

    1999-08-10

    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.

  16. Are Carotid Stent Fractures Clinically Significant?

    SciTech Connect (OSTI)

    Garcia-Toca, Manuel; Rodriguez, Heron E.; Naughton, Peter A. [Northwestern University Feinberg School of Medicine, Division of Vascular Surgery (United States); Keeling, Aiofee [Northwestern University Feinberg School of Medicine, Department of Radiology (United States); Phade, Sachin V.; Morasch, Mark D.; Kibbe, Melina R.; Eskandari, Mark K., E-mail: meskanda@nmh.org [Northwestern University Feinberg School of Medicine, Division of Vascular Surgery (United States)

    2012-04-15

    Purpose: Late stent fatigue is a known complication after carotid artery stenting (CAS) for cervical carotid occlusive disease. The purpose of this study was to determine the prevalence and clinical significance of carotid stent fractures. Materials and Methods: A single-center retrospective review of 253 carotid bifurcation lesions treated with CAS and mechanical embolic protection from April 2001 to December 2009 was performed. Stent integrity was analyzed by two independent observers using multiplanar cervical plain radiographs with fractures classified into the following types: type I = single strut fracture; type II = multiple strut fractures; type III = transverse fracture; and type IV = transverse fracture with dislocation. Mean follow-up was 32 months. Results: Follow-up imaging was completed on 106 self-expanding nitinol stents (26 closed-cell and 80 open-cell stents). Eight fractures (7.5%) were detected (type I n = 1, type II n = 6, and type III n = 1). Seven fractures were found in open-cell stents (Precise n = 3, ViVEXX n = 2, and Acculink n = 2), and 1 fracture was found in a closed-cell stent (Xact n = 1) (p = 0.67). Only a previous history of external beam neck irradiation was associated with fractures (p = 0.048). No associated clinical sequelae were observed among the patients with fractures, and only 1 patient had an associated significant restenosis ({>=}80%) requiring reintervention. Conclusions: Late stent fatigue after CAS is an uncommon event and rarely clinically relevant. Although cell design does not appear to influence the occurrence of fractures, lesion characteristics may be associated risk factors.

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

    E-Print Network [OSTI]

    Berthelot, Jan Marie

    1990-01-01

    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...

  18. Method of fracturing a geological formation

    DOE Patents [OSTI]

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

    1990-01-01

    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.

  19. Hydraulic Fracturing Poster | Department of Energy

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

    Educational poster graphically displaying the key components of hydraulic fracturing. Teachers: If you would like hard copies of this poster sent to you, please contact the FE...

  20. Regional Analysis And Characterization Of Fractured Aquifers...

    Open Energy Info (EERE)

    Regional Analysis And Characterization Of Fractured Aquifers In The Virginia Blue Ridge And Piedmont Provinces Jump to: navigation, search OpenEI Reference LibraryAdd to library...

  1. Microseismic Tracer Particles for Hydraulic Fracturing

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

    The trend toward production of hydrocarbons from unconventional reservoirs (tight gas, shale oilgas) has caused a large increase in the use of hydraulic fracture stimulation of...

  2. Structural Settings Of Hydrothermal Outflow- Fracture Permeability...

    Open Energy Info (EERE)

    long-lived hydrothermal flow despite potential clogging of fractures due to mineral precipitation. As fault systems evolve, propagation, interaction, and linkage of fault segments...

  3. Using microstructure observations to quantify fracture properties and improve reservoir simulations. Final report, September 1998

    SciTech Connect (OSTI)

    Laubach, S.E.; Marrett, R.; Rossen, W.; Olson, J.; Lake, L.; Ortega, O.; Gu, Y.; Reed, R.

    1999-01-01

    The research for this project provides new technology to understand and successfully characterize, predict, and simulate reservoir-scale fractures. Such fractures have worldwide importance because of their influence on successful extraction of resources. The scope of this project includes creation and testing of new methods to measure, interpret, and simulate reservoir fractures that overcome the challenge of inadequate sampling. The key to these methods is the use of microstructures as guides to the attributes of the large fractures that control reservoir behavior. One accomplishment of the project research is a demonstration that these microstructures can be reliably and inexpensively sampled. Specific goals of this project were to: create and test new methods of measuring attributes of reservoir-scale fractures, particularly as fluid conduits, and test the methods on samples from reservoirs; extrapolate structural attributes to the reservoir scale through rigorous mathematical techniques and help build accurate and useful 3-D models of the interwell region; and design new ways to incorporate geological and geophysical information into reservoir simulation and verify the accuracy by comparison with production data. New analytical methods developed in the project are leading to a more realistic characterization of fractured reservoir rocks. Testing diagnostic and predictive approaches was an integral part of the research, and several tests were successfully completed.

  4. Efficient Double-Beam Characterization for Fractured Reservoir

    E-Print Network [OSTI]

    Zheng, Yingcai

    We proposed an efficient target-oriented method to characterize seismic properties of fractured reservoirs: the spacing between fractures and the fracture orientation. Based on the diffraction theory, the scattered wave ...

  5. Characterization of dipping fractures in transversely isotropic background

    E-Print Network [OSTI]

    Tsvankin, Ilya

    Characterization of dipping fractures in transversely isotropic background Vladimir Grechka incidence becomes dependent on fracture infill (saturation). A complete medium-characterization procedure for the vertical and NMO velocities. Keywords.--fracture characterization, azimuthal anisotropy, multicomponent

  6. Incorporating Rigorous Height Determination into Unified Fracture Design 

    E-Print Network [OSTI]

    Pitakbunkate, Termpan

    2010-10-12

    Hydraulic fracturing plays an important role in increasing production rate in tight reservoirs. The performance of the reservoir after fracturing can be observed from the productivity index. This parameter is dependent on the fracture geometry...

  7. A PKN Hydraulic Fracture Model Study and Formation Permeability Determination 

    E-Print Network [OSTI]

    Xiang, Jing

    2012-02-14

    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...

  8. FINITE FRACTURE MECHANICS OF MATRIX MICROCRACKING IN COMPOSITES

    E-Print Network [OSTI]

    Nairn, John A.

    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

  9. Seismic characterization of fractured reservoirs using 3D double beams

    E-Print Network [OSTI]

    Zheng, Yingcai

    2012-01-01

    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 ...

  10. Ductile fracture modeling : theory, experimental investigation and numerical verification

    E-Print Network [OSTI]

    Xue, Liang, 1973-

    2007-01-01

    The fracture initiation in ductile materials is governed by the damaging process along the plastic loading path. A new damage plasticity model for ductile fracture is proposed. Experimental results show that fracture ...

  11. Brittle and ductile fracture of semiconductor nanowires --molecular dynamics simulations

    E-Print Network [OSTI]

    Cai, Wei

    Brittle and ductile fracture of semiconductor nanowires -- molecular dynamics simulations Keonwook November 9, 2006 Abstract Fracture of silicon and germanium nanowires in tension at room temperature potentials predict brittle fracture initiated by crack nucleation from the surface, most potentials predict

  12. Stochastic multiscale models for fracture analysis of functionally graded materials

    E-Print Network [OSTI]

    Rahman, Sharif

    Stochastic multiscale models for fracture analysis of functionally graded materials Arindam three multiscale models, including sequential, invasive, and concurrent models, for fracture analysis methods for fracture reliability analysis. The par- ticle volume fractions, defined by a generic

  13. UNIVERSITY OF CALGARY Modeling Fracture Formation on Growing Surfaces

    E-Print Network [OSTI]

    Prusinkiewicz, Przemyslaw

    UNIVERSITY OF CALGARY Modeling Fracture Formation on Growing Surfaces by Pavol Federl A THESIS Fracture Formation on Growing Surfaces" submitted by Pavol Federl in partial fulfillment This thesis describes a framework for modeling fracture formation on differentially growing, bi- layered

  14. State-of-the-art report on piping fracture mechanics

    SciTech Connect (OSTI)

    Wilkowski, G.M.; Olson, R.J.; Scott, P.M.

    1998-01-01

    This report is an in-depth summary of the state-of-the-art in nuclear piping fracture mechanics. It represents the culmination of 20 years of work done primarily in the US, but also attempts to include important aspects from other international efforts. Although the focus of this work was for the nuclear industry, the technology is also applicable in many cases to fossil plants, petrochemical/refinery plants, and the oil and gas industry. In compiling this detailed summary report, all of the equations and details of the analysis procedure or experimental results are not necessarily included. Rather, the report describes the important aspects and limitations, tells the reader where he can go for further information, and more importantly, describes the accuracy of the models. Nevertheless, the report still contains over 150 equations and over 400 references. The main sections of this report describe: (1) the evolution of piping fracture mechanics history relative to the developments of the nuclear industry, (2) technical developments in stress analyses, material property aspects, and fracture mechanics analyses, (3) unresolved issues and technically evolving areas, and (4) a summary of conclusions of major developments to date.

  15. Seismic characterization of vertical fractures described as general linear-slip interfaces

    E-Print Network [OSTI]

    Tsvankin, Ilya

    Seismic characterization of vertical fractures described as general linear-slip interfaces Vladimir School of Mines, Golden, CO 80401-1887, USA (currently at Shell International Exploration and Production International Exploration and Production Inc., Bellaire Technology Center, 3737 Bellaire Blvd., Houston, TX

  16. Numerical Modeling of Fracture Permeability Change in Naturally Fractured Reservoirs Using a Fully Coupled Displacement Discontinuity Method. 

    E-Print Network [OSTI]

    Tao, Qingfeng

    2010-07-14

    Fractures are the main flow channels in naturally fractured reservoirs. Therefore the fracture permeability is a critical parameter to production optimization and reservoir management. Fluid pressure reduction caused by production induces...

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

    E-Print Network [OSTI]

    Rutqvist, J.

    2011-01-01

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

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

    E-Print Network [OSTI]

    Cotte, F.P.

    2012-01-01

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

  19. Images of Fracture Sustainability Test on Stripa Granite

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Tim Kneafsey

    2014-05-11

    Images of the Stripa Granite core before and after the fracture sustainability test. Photos of fracture faces of Stripa Granite core.

  20. Predicting fracture in micron-scale polycrystalline silicon MEMS...

    Office of Scientific and Technical Information (OSTI)

    Predicting fracture in micron-scale polycrystalline silicon MEMS structures. Citation Details In-Document Search Title: Predicting fracture in micron-scale polycrystalline silicon...

  1. Final Report Multiazimuth Seismic Diffraction Imaging for Fracture...

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

    ...67 Figure 2.6 Fracture path and required pressure for critical growth, SH0.1...69 Figure 2.7 Fracture path and required...

  2. Images of Fracture Sustainability Test on Stripa Granite

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Tim Kneafsey

    Images of the Stripa Granite core before and after the fracture sustainability test. Photos of fracture faces of Stripa Granite core.

  3. Integration of well test analysis into naturally fractured reservoir simulation 

    E-Print Network [OSTI]

    Perez Garcia, Laura Elena

    2006-04-12

    Naturally fractured reservoirs (NFR) represent an important percentage of the worldwide hydrocarbon reserves and production. Reservoir simulation is a fundamental technique in characterizing this type of reservoir. Fracture ...

  4. Fractured rock stress-permeability relationships from in situ...

    Office of Scientific and Technical Information (OSTI)

    Fractured rock stress-permeability relationships from in situ data and effects of temperature and chemical-mechanical couplings Citation Details In-Document Search Title: Fractured...

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

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

    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....

  6. Elastic properties of saturated porous rocks with aligned fractures

    E-Print Network [OSTI]

    2003-12-02

    Elastic properties of fluid saturated porous media with aligned fractures can be studied using the ...... that are in hydraulic equilibrium with the fractures, the.

  7. Irradiation Effects on Human Cortical Bone Fracture Behavior

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

    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...

  8. Thermal-hydrologic-mechanical behavior of single fractures in...

    Office of Scientific and Technical Information (OSTI)

    Thermal-hydrologic-mechanical behavior of single fractures in EGS reservoirs Citation Details In-Document Search Title: Thermal-hydrologic-mechanical behavior of single fractures...

  9. Detection and Characterization of Natural and Induced Fractures...

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

    Characterization of Natural and Induced Fractures for the Development of Enhanced Geothermal Systems Detection and Characterization of Natural and Induced Fractures for the...

  10. 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...

  11. Three-dimensional Modeling of Fracture Clusters in Geeothermal...

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

    Geeothermal Reservoirs Three-dimensional Modeling of Fracture Clusters in Geeothermal Reservoirs Three-dimensional Modeling of Fracture Clusters in Geeothermal Reservoirs...

  12. Fracture of solid state laser slabs

    SciTech Connect (OSTI)

    Marion, J.E.

    1986-07-01

    Fracture due to thermal stress limits the power output potential of modern, high average power slab lasers. Here the criteria for slab fracture and the nature of the surface flaws which constitute the strength-controlling defects are reviewed. Specific fracture data for gadolinium scandium gallium garnet and LHG-5 phosphate glass with different surface finishes are evaluated in the context of assigning appropriate slab operating parameters using Wiebull statistics. These examples illustrate both the danger of design using brittle components without adequate fracture testing, and the inadequacy of design methods which use a fixed safety factor, for this class of materials. Further consideration reveals that operation of slab lasers in contact with an aqueous coolant may lead to strength degradation with time. Finally, the evolution of the failure process in which a characteristic midplane crack forms is outlined, and the pertinent parameters for avoiding slab fracture are identified.

  13. Hydraulic fracturing slurry transport in horizontal pipes

    SciTech Connect (OSTI)

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

    1990-09-01

    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.

  14. Self-potential observations during hydraulic fracturing

    SciTech Connect (OSTI)

    Moore, Jeffrey R.; Glaser, Steven D.

    2007-09-13

    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.

  15. CX-100004: Categorical Exclusion Determination

    Office of Energy Efficiency and Renewable Energy (EERE)

    Leveraging a Fundamental Understanding of Fracture Flow, Dynamic Permeability Enhancement, and Induced Seismicity to Improve Geothermal Energy Production Award Number: DE-EE0006762 CX(s) Applied: A9, B3.6 Geothermal Technologies Date: 08/27/2014 Location(s): Pennsylvania Office(s): Golden Field Office

  16. CX-010963: Categorical Exclusion Determination

    Office of Energy Efficiency and Renewable Energy (EERE)

    Development of Nanoparticle-Stabilized Foams To Improve Performance of Water-less Hydraulic Fracturing CX(s) Applied: A1, B3.6 Date: 09/16/2013 Location(s): Texas Offices(s): National Energy Technology Laboratory

  17. CX-012292: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Water Treatment System for Effective Acid Mine Drainage Water Use in Hydraulic Fracturing CX(s) Applied: B3.6 Date: 06/03/2014 Location(s): Indiana, Texas, Ohio, Pennsylvania, Georgia Offices(s): National Energy Technology Laboratory

  18. Fracture-resistant lanthanide scintillators

    DOE Patents [OSTI]

    Doty, F. Patrick (Livermore, CA)

    2011-01-04

    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.

  19. Research paper Thermalmechanical modeling of cooling history and fracture development

    E-Print Network [OSTI]

    Kattenhorn, Simon

    from cooling fracture patterns in field examples on the eastern Snake River Plain, Idaho, and highlight

  20. 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.

  1. Calibration of hydraulic and tracer tests in fractured media

    E-Print Network [OSTI]

    Politècnica de Catalunya, Universitat

    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

  2. Reply to Davies: Hydraulic fracturing remains a possible mechanism for

    E-Print Network [OSTI]

    Jackson, Robert B.

    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

  3. Statistical RKR Modeling of Mixed-Mode Fracture

    E-Print Network [OSTI]

    Ritchie, Robert

    Statistical RKR Modeling of Mixed-Mode Fracture in a Brittle Functionally Graded Material by T. L-calibration for fracture mechanics sample with modulus gradient ·Calculate effect of gradient slope on ·predicted fracture fK x II ijII I ijI ij 2 )( 2 )( )exp( #12;·The RKR fracture model correlates the onset

  4. International Journal of Fracture volume 5, number 2, 167181 (2009)

    E-Print Network [OSTI]

    Nairn, John A.

    2009-01-01

    International Journal of Fracture volume 5, number 2, 167­181 (2009) Analytical and Numerical March 2009 Abstract At the onset of fracture in materials with process zones, the fracture resis- tance with bridging zones. The simulation method includes pure fracture mechanics and pure cohesive zone models

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

    E-Print Network [OSTI]

    Liu, Yuwei

    2013-01-01

    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 ...

  6. Three dimensional geologic modeling of a fractured reservoir, Saudi Arabia

    SciTech Connect (OSTI)

    Luthy, S.T.; Grover, G.A. [Saudi Aramco, Dhahran (Saudi Arabia)

    1995-11-01

    A geological assessment of a large carbonate reservoir in Saudi Arabia shows that it is a Type 2 fractured reservoir in which fractures provide the essential permeability. Intercrystalline microporosity, found within the basinally deposited mudstones and wackestones, is the dominant porosity type. Near-vertical, east-west-oriented extension fractures are preferentially localized in low-to-moderate porosities associated with stylolites. Porosity/fracture density relationships, combined with the results of structural curvature mapping, yielded a 3-dimensional model of fracture density. Fracture permeability and fracture porosity distributions were generated by integrating fracture density modeling results with average fracture aperture information derived from well test data. Dramatic differences exist between matrix- and fracture-related porosity, permeability models that help explain observed production behavior within the field. These models are being used by reservoir and simulation engineers for daily reservoir management, history matching, and long-term development drilling planning.

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

    E-Print Network [OSTI]

    Ritchie, Robert

    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

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

    E-Print Network [OSTI]

    Collins, Gary S.

    · 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

  9. Predicting hip fracture type with cortical bone mapping (CBM) in the Osteoporotic Fractures in Men (MrOS) study

    E-Print Network [OSTI]

    Drummond, Tom

    Predicting hip fracture type with cortical bone mapping (CBM) in the Osteoporotic Fractures in Men, for the Osteoporotic Fractures in Men (MrOS) study CUED/F-INFENG/TR 695 January 2015 Cambridge University Engineering;1 Abstract Hip fracture risk is known to be related to material properties of the proximal femur, but prospec

  10. 3-D description of fracture surfaces and stress-sensitivity analysis for naturally fractured reservoirs

    SciTech Connect (OSTI)

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

    1997-08-01

    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.

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

    E-Print Network [OSTI]

    Forbis, Robert E.

    2014-01-01

    lic fracturing, or “fracking,” where chemically treatedreduced by the advent of fracking and directional drilling.That began to be developed, fracking is fundamental to that,

  12. Fractured: Experts examine the contentious issue of hydraulic fracturing water use 

    E-Print Network [OSTI]

    Wythe, Kathy

    2013-01-01

    Story by Kathy Wythe FRACTURED Experts examine the contentious issue of hydraulic fracturing water use In a state where oil and gas are king, and water is? in words commonly a?ributed to Mark Twain? ?for ?ghting over,? an unconventional method... that uses water to extract oil and gas from Texas? underground ?elds is causing passionate debate. ?is method?hydraulic fracturing?uses water and other ?uids under pressure to fracture or crack shale rock, releasing oil and gas from the rock. Combined...

  13. Detecting Fractures Using Technology at High Temperatures and Depths -

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum Based| Department8, 20153Danielthrough theKDesertDesigningCourse

  14. NFFLOW: A reservoir simulator incorporating explicit fractures (SPE 153890)

    SciTech Connect (OSTI)

    Boyle, E.J.; Sams, W.N.

    2012-01-01

    NFFLOW is a research code that quickly and inexpensively simulates flow in moderately fractured reservoirs. It explicitly recognizes fractures separately from rock matrix. In NFFLOW fracture flow is proportional to the pressure gradient along the fracture, and flow in the rock matrix is determined by Darcy’s Law. The two flow mechanisms are coupled through the pressure gradient between a fracture and its adjacent rock matrix. Presented is a promising change to NFFLOW that allows for flow across a rock matrix block.

  15. Multiphase flow in fractured porous media

    SciTech Connect (OSTI)

    Firoozabadi, A.

    1995-02-01

    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.

  16. Anomalous transport through porous and fractured media

    E-Print Network [OSTI]

    Kang, Peter Kyungchul

    2014-01-01

    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 ...

  17. Fracture of surface cracks loaded in bending

    SciTech Connect (OSTI)

    Chao, Y.J.; Reuter, W.G.

    1997-12-31

    Theoretical background of the constraint effect in brittle fracture of solids is reviewed. Fracture test data from D6-aC, a high strength steel, using three-point-bend (SE(B)) specimens and surface cracked plate (SC(B)) specimens under bending are presented. It is shown that the SE(B) data has an elevated fracture toughness for increasing a/W, i.e., a crack geometry with a larger T/K corresponds to a higher K{sub c} which is consistent with the theoretical prediction. The fundamental fracture properties, i.e., the critical strain and the critical distance, determined from the SE(B) test data are then applied to the interpretation and prediction of the SC(B) test data. Reasonable agreement is achieved for the crack growth initiation site and the load.

  18. Freeze fracturing of elastic porous media

    E-Print Network [OSTI]

    Vlahou, Ioanna

    2012-06-12

    is the growth of ice lenses in saturated cohesive soils. I present results for typical soil parameters and find good agreement between our theory and experimental observations of growth rates and minimum undercoolings required for fracturing....

  19. Universal asymptotic umbrella for hydraulic fracture modeling

    E-Print Network [OSTI]

    Linkov, Aleksandr M

    2014-01-01

    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.

  20. Poroelastic response of orthotropic fractured porous media

    SciTech Connect (OSTI)

    Berryman, J.G.

    2010-12-01

    An algorithm is presented for inverting either laboratory or field poroelastic data for all the drained constants of an anisotropic (specifically orthotropic) fractured poroelastic system. While fractures normally weaken the system by increasing the mechanical compliance, any liquids present in these fractures are expected to increase the stiffness somewhat, thus negating to some extent the mechanical weakening influence of the fractures themselves. The analysis presented quantifies these effects and shows that the key physical variable needed to account for the pore-fluid effects is a factor of (1 - B), where B is Skempton's second coe#14;fficient and satisfies 0 {<=} #20; B < 1. This scalar factor uniformly reduces the increase in compliance due to the presence of communicating fractures, thereby stiffening the fractured composite medium by a predictable amount. One further goal of the discussion is to determine how many of the poroelastic constants need to be known by other means in order to determine the rest from remote measurements, such as seismic wave propagation data in the field. Quantitative examples arising in the analysis show that, if the fracture aspect ratio a{sub f} ~ 0.1 and the pore fluid is liquid water, then for several cases considered Skempton's B ~ 0:9, so the stiffening effect of the pore-liquid reduces the change in compliance due to the fractures by a factor 1-B ~ 0.1, in these examples. The results do however depend on the actual moduli of the unfractured elastic material, as well as on the pore-liquid bulk modulus, so these quantitative predictions are just examples, and should not be treated as universal results. Attention is also given to two previously unremarked poroelastic identities, both being useful variants of Gassmann's equations for homogeneous -- but anisotropic -- poroelasticity. Relationships to Skempton's analysis of saturated soils are also noted. The paper concludes with a discussion of alternative methods of analyzing and quantifying fluid-substitution behavior in poroelastic systems, especially for those systems having heterogeneous constitution.

  1. Accounting for Remaining Injected Fracturing Fluid 

    E-Print Network [OSTI]

    Zhang, Yannan

    2013-12-06

    wells: liquid film movement along the walls of the pipe, and liquid droplets associated with the high velocity gas. The critical condition to transport liquids from gas wells is the high enough gas velocity to transport the largest drops... critical value, the critical-gas velocity changes with the concentration. Kuru et al. (2013) suggested that non-recovered water can also accumulate in the fractures. The height of hydraulic fractures in horizontal wells is usually from tens to hundreds...

  2. Dynamic Fracture Toughness of Polymer Composites 

    E-Print Network [OSTI]

    Harmeet Kaur

    2012-02-14

    to fully charac- terize material properties before using them for applications in critical industries, like that of defense or transport. In this project, the focus is on determining dy- namic fracture toughness property of ber reinforced polymer... : : : : 33 III Wave speeds and traveling times making a particular angle to laminate ber direction : : : : : : : : : : : : : : : : : : : : : : : : : 37 IV Mode-I quasi-static fracture toughness values (KIC) : : : : : : : : : : 45 V Mode-II quasi...

  3. Identifying Fracture Types and Relative Ages Using Fluid Inclusion Stratigraphy

    SciTech Connect (OSTI)

    Dilley, Lorie M.; Norman, David; Owens, Lara

    2008-06-30

    Enhanced Geothermal Systems (EGS) are designed to recover heat from the subsurface by mechanically creating fractures in subsurface rocks. Understanding the life cycle of a fracture in a geothermal system is fundamental to the development of techniques for creating fractures. Recognizing the stage of a fracture, whether it is currently open and transmitting fluids; if it recently has closed; or if it is an ancient fracture would assist in targeting areas for further fracture stimulation. Identifying dense fracture areas as well as large open fractures from small fracture systems will also assist in fracture stimulation selection. Geothermal systems are constantly generating fractures, and fluids and gases passing through rocks in these systems leave small fluid and gas samples trapped in healed microfractures. Fluid inclusions trapped in minerals as the fractures heal are characteristic of the fluids that formed them, and this signature can be seen in fluid inclusion gas analysis. Our hypothesis is that fractures over their life cycle have different chemical signatures that we can see in fluid inclusion gas analysis and by using the new method of fluid inclusion stratigraphy (FIS) the different stages of fractures, along with an estimate of fracture size can be identified during the well drilling process. We have shown with this study that it is possible to identify fracture locations using FIS and that different fractures have different chemical signatures however that signature is somewhat dependent upon rock type. Open, active fractures correlate with increase concentrations of CO2, N2, Ar, and to a lesser extent H2O. These fractures would be targets for further enhancement. The usefulness of this method is that it is low cost alternative to current well logging techniques and can be done as a well is being drilled.

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

    E-Print Network [OSTI]

    Doe, T.

    2010-01-01

    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

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

    E-Print Network [OSTI]

    Doe, T.

    2010-01-01

    u l y 2 , 1 9 8 1 HYDRAULIC FRACTURING AND OVERCORING STRESSI nun LBL-12478 HYDRAULIC FRACTURING AND OVERCORING STRESSstress. n HYDRAULIC FRACTURING EQUIPMENT AND PROCEDURES The

  6. Gas Permeability of Fractured Sandstone/Coal Samples under Variable Confining Pressure

    E-Print Network [OSTI]

    Liu, Weiqun; Li, Yushou; Wang, Bo

    2010-01-01

    Permeability of Fractured Sandstone/Coal Samples Smeulders,8 Gas Permeability of Fractured Sandstone/Coal Samples underthe fractured samples of sandstone and coal and obtain their

  7. Fractures in complex fluids: the case of transient networks

    E-Print Network [OSTI]

    Christian Ligoure; Serge Mora

    2013-01-15

    We present a comprehensive review of the current state of fracture phenomena in transient networks, a wide class of viscoelastic fluids. We will first define what is a fracture in a complex fluid, and recall the main structural and rheological properties of transient networks. Secondly, we review experimental reports on fractures of transient networks in several configurations: shear-induced fractures, fractures in Hele-Shaw cells and fracture in extensional geometries (filament stretching rheometry and pendant drop experiments), including fracture propagation. The tentative extension of the concepts of brittleness and ductility to the fracture mechanisms in transient networks is also discussed. Finally, the different and apparently contradictory theoretical approaches developed to interpret fracture nucleation will be addressed and confronted to experimental results. Rationalized criteria to discriminate the relevance of these different models will be proposed.

  8. Optimizing Fracture Treatments in a Mississippian "Chat" Reservoir, South-Central Kansas

    SciTech Connect (OSTI)

    K. David Newell; Saibal Bhattacharya; Alan Byrnes; W. Lynn Watney; Willard Guy

    2005-10-01

    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.

  9. Thermochemically Driven Gas-Dynamic Fracturing (TDGF)

    SciTech Connect (OSTI)

    Michael Goodwin

    2008-12-31

    This report concerns efforts to increase oil well productivity and efficiency via a method of heating the oil-bearing rock of the well, a technique known as Thermochemical Gas-Dynamic Fracturing (TGDF). The technique uses either a chemical reaction or a combustion event to raise the temperature of the rock of the well, thereby increasing oil velocity, and oil pumping rate. Such technology has shown promise for future application to both older wellheads and also new sites. The need for such technologies in the oil extraction field, along with the merits of the TGDF technology is examined in Chapter 1. The theoretical basis underpinning applications of TGDF is explained in Chapter 2. It is shown that productivity of depleted well can be increased by one order of magnitude after heating a reservoir region of radius 15-20 m around the well by 100 degrees 1-2 times per year. Two variants of thermal stimulation are considered: uniform heating and optimal temperature distribution in the formation region around the perforation zone. It is demonstrated that the well productivity attained by using equal amounts of thermal energy is higher by a factor of 3 to 4 in the case of optimal temperature distribution as compared to uniform distribution. Following this theoretical basis, two practical approaches to applying TDGF are considered. Chapter 3 looks at the use of chemical intiators to raise the rock temperature in the well via an exothermic chemical reaction. The requirements for such a delivery device are discussed, and several novel fuel-oxidizing mixtures (FOM) are investigated in conditions simulating those at oil-extracting depths. Such FOM mixtures, particularly ones containing nitric acid and a chemical initiator, are shown to dramatically increase the temperature of the oil-bearing rock, and thus the productivity of the well. Such tests are substantiated by preliminary fieldwork in Russian oil fields. A second, more cost effective approach to TGDF is considered in Chapter 4: use of diesel-fuel to raise the rock temperature by a combustion process in the well. The requirements for such a Gas-Vapor Generator are laid out, and the development of a prototype machine is explained. This is backed up with laboratory experiments showing that the fuel-water mixture used does significantly increase the viscosity of the oil samples. The prototype Gas-Vapor Generator is shown to be able to operate at temperatures of 240 C and pressures of 200 atm. Unfortunately, geopolitical and economic factors outside of our control led to the cancellation of the project before the field testing phase of the generator could be commenced. Nevertheless, it is to be hoped that this report demonstrates both the feasibility and desirability of the Gas-Vapor Generator approach to the application of TDGF technology in both existing and new wells, and provides a foundation for further research in the future.

  10. Oil recovery from naturally fractured reservoirs by steam injection methods. Final report

    SciTech Connect (OSTI)

    Reis, J.C.; Miller, M.A.

    1995-05-01

    Oil recovery by steam injection is a proven, successful technology for nonfractured reservoirs, but has received only limited study for fractured reservoirs. Preliminary studies suggest recovery efficiencies in fractured reservoirs may be increased by as much as 50% with the application of steam relative to that of low temperature processes. The key mechanisms enhancing oil production at high temperature are the differential thermal expansion between oil and the pore volume, and the generation of gases within matrix blocks. Other mechanisms may also contribute to increased production. These mechanisms are relatively independent of oil gravity, making steam injection into naturally fractured reservoirs equally attractive to light and heavy oil deposits. The objectives of this research program are to quantify the amount of oil expelled by these recovery mechanisms and to develop a numerical model for predicting oil recovery in naturally fractured reservoirs during steam injection. The experimental study consists of constructing and operating several apparatuses to isolate each of these mechanisms. The first measures thermal expansion and capillary imbibition rates at relatively low temperature, but for various lithologies and matrix block shapes. The second apparatus measures the same parameters, but at high temperatures and for only one shape. A third experimental apparatus measures the maximum gas saturations that could build up within a matrix block. A fourth apparatus measures thermal conductivity and diffusivity of porous media. The numerical study consists of developing transfer functions for oil expulsion from matrix blocks to fractures at high temperatures and incorporating them, along with the energy equation, into a dual porosity thermal reservoir simulator. This simulator can be utilized to make predictions for steam injection processes in naturally-fractured reservoirs. Analytical models for capillary imbibition have also been developed.

  11. Three-dimensional Modeling of Acid Transport and Etching in a Fracture 

    E-Print Network [OSTI]

    Oeth, Cassandra V

    2013-11-25

    Acid fracture stimulation generates higher well production but requires engineering design for treatment optimization. To quantify the cost and benefit of a particular acid fracture treatment an engineer must predict the resulting fracture’s...

  12. Mechanical Behavior of Small-Scale Channels in Acid-etched Fractures 

    E-Print Network [OSTI]

    Deng, Jiayao

    2011-02-22

    The conductivity of acid-etched fractures highly depends on spaces along the fracture created by uneven etching of the fracture walls remaining open after fracture closure. Formation heterogeneities such as variations of mineralogy and permeability...

  13. Austin chalk fracture mapping using frequency data derived from seismic data 

    E-Print Network [OSTI]

    Najmuddin, Ilyas Juzer

    2004-09-30

    , is difficult on seismic sections. Fracturing changes the rock properties and therefore the attributes of the seismic data reflecting off the fractured interface, and data passing through the fractured layers. Fractures have a scattering effect on seismic energy...

  14. A microstructural study of the extension-to-shear fracture transition in Carrara Marble 

    E-Print Network [OSTI]

    Rodriguez, Erika

    2005-11-01

    Triaxial extension experiments on Carrara Marble demonstrate that there is a continuous transition from extension to shear fracture on the basis of mechanical behavior, macroscopic fracture orientation and fracture morphology where hybrid fractures...

  15. Investigation of the influence of stress shadows on horizontal hydraulic fractures from adjacent lateral wells

    E-Print Network [OSTI]

    Investigation of the influence of stress shadows on horizontal hydraulic fractures from adjacent: Unconventional hydraulic fracturing Stress shadow Adjacent lateral wells Simulfrac and zipperfrac Numerical the simultaneous or near simultaneous hydraulic fracturing of adjacent lateral wells to maximize the fracture

  16. A robust method for fracture orientation and density detection from seismic scattered energy

    E-Print Network [OSTI]

    Fang, Xinding

    2011-01-01

    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 ...

  17. Nonmonotonic fracture behavior of polymer nanocomposites

    E-Print Network [OSTI]

    Janaina G. de Castro; Rojman Zargar; Mehdi Habibi; Samet H. Varol; Sapun H. Parekh; Babak Hosseinkhani; Mokhtar Adda-Bedia; Daniel Bonn

    2015-06-02

    Polymer composite materials are widely used for their exceptional mechanical properties, notably their ability to resist large deformations. Here we examine the failure stress and strain of rubbers reinforced by varying amounts of nano-sized silica particles. We find that small amounts of silica increase the fracture stress and strain, but too much filler makes the material become brittle and consequently fracture happens at small deformations. We thus find that as a function of the amount of filler there is an optimum in the breaking resistance at intermediate filler concentrations. We use a modified Griffith theory to establish a direct relation between the material properties and the fracture behavior that agrees with the experiment.

  18. Hydrothermal coupling in a rough fracture

    E-Print Network [OSTI]

    Neuville, A; Schmittbuhl, J; Neuville, Am\\'{e}lie; Toussaint, Renaud; Schmittbuhl, Jean

    2006-01-01

    Heat exchange during laminar flow is studied at the fracture scale on the basis of the Stokes equation. We used a synthetic aperture model (a self-affine model) that has been shown to be a realistic geometrical description of the fracture morphology. We developed a numerical modelling using a finite difference scheme of the hydrodynamic flow and its coupling with an advection/conduction description of the fluid heat. As a first step, temperature within the surrounding rock is supposed to be constant. Influence of the fracture roughness on the heat flux through the wall, is estimated and a thermalization length is shown to emerge. Implications for the Soultz-sous-For\\^{e}ts geothermal project are discussed.

  19. A cubic matrix-fracture geometry model for radial tracer flow in naturally fractured reservoirs

    SciTech Connect (OSTI)

    Jetzabeth Ramirez-Sabag; Fernando Samaniego V.

    1992-01-01

    This study presents a general solution for the radial flow of tracers in naturally fractured reservoirs, with cubic blocks matrix-fracture geometry. Continuous and finite step injection of chemical and radioactive tracers are considered. The reservoir is treated as being composed of two regions: a mobile where dispersion and convection take place and a stagnant where only diffusion and adsorption are allowed. Radioactive decay is considered in both regions. The model of this study is thoroughly compared under proper simplified conditions to those previously presented in the literature. The coupled matrix to fracture solution in the Laplace space is numerically inverted by means of the Crump algorithm. A detailed validation of the model with respect to solutions previously presented and/or simplified physical conditions solutions (i.e., homogeneous case) or limit solutions (i.e., naturally fractured nearly homogeneous) was carried out. The influence of the three of the main dimensionless parameters that enter into the solution was carefully investigated. A comparison of results for three different naturally fractured systems, vertical fractures (linear flow), horizontal fractures (radial flow) and the cubic geometry model of this study, is presented.

  20. Technology Assessment TECHNOLOGY ASSESSMENT

    E-Print Network [OSTI]

    Rock, Chris

    Technology Assessment 10/14/2004 1 TECHNOLOGY ASSESSMENT STRATEGIC PLAN MISSION STATEMENT Support the Mission of Texas Tech University and the TTU Information Technology Division by providing timely and relevant information and assistance in current and emerging technologies and their practical applications

  1. Bioscience Technology Bioscience Technology

    E-Print Network [OSTI]

    Vertes, Akos

    Bioscience Technology Bioscience Technology Advantage Business Media 100 Enterprise Drive Rockaway, co-director of George Washington University's Institute for Proteomics Technology and Applications-by-point. Manufacturers have stampeded to offer the new technology. Applied Biosystems got out in front in 2004 when

  2. Simulation on Discrete Fracture Network Using Flexible Voronoi Gridding 

    E-Print Network [OSTI]

    Syihab, Zuher

    2011-02-22

    Fractured reservoirs are generally simulated using Warren and Root26 dual-porosity (DP) approach. The main assumption of this approach is that the geometry of fractures are uniformly distributed and interconnected in ...

  3. 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.

  4. Effectiveness of microseismic monitoring for optimizing hydraulic fracturing in California

    E-Print Network [OSTI]

    Alampi, Ann M

    2014-01-01

    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 ...

  5. Numerical Modeling of Hydraulic Fracturing in Oil Sands

    E-Print Network [OSTI]

    2008-11-16

    Hydraulic fracturing is a widely used and e cient technique for enhancing oil extraction from heavy oil sands ..... phenomenon are the main issues involved in hydraulic fracturing. ..... energy ux due to conduction and convection: Lei = @T. @xi.

  6. The Role of Acidizing in Proppant Fracturing in Carbonate Reservoirs 

    E-Print Network [OSTI]

    Densirimongkol, Jurairat

    2010-10-12

    Today, optimizing well stimulation techniques to obtain maximum return of investment is still a challenge. Hydraulic fracturing is a typical application to improve ultimate recovery from oil and gas reservoirs. Proppant fracturing has become one...

  7. Selection of fracture fluid for stimulating tight gas reservoirs 

    E-Print Network [OSTI]

    Malpani, Rajgopal Vijaykumar

    2007-04-25

    Essentially all producing wells drilled in tight gas sands and shales are stimulated using hydraulic fracture treatments. The development of optimal fracturing procedures, therefore, has a large impact on the long-term economic viability...

  8. Acid Fracturing Feasibility Study for Heterogeneous Carbonate Formation 

    E-Print Network [OSTI]

    Suleimenova, Assiya

    2015-03-03

    Acid fracturing is a stimulation technique that is commonly used by the industry to increase productivity or injectivity of wells in carbonate reservoirs. To determine a feasibility of acid fracturing treatment for a heterogeneous formation...

  9. Experimental Study of Acid Fracture Conductivity of Austin Chalk Formation 

    E-Print Network [OSTI]

    Nino Penaloza, Andrea

    2013-05-01

    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...

  10. Fracture characterization from seismic measurements in a borehole

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    2015-01-01

    Fracture characterization is important for optimal recovery of hydrocarbons. In this thesis, we develop techniques to characterize natural and hydraulic fractures using seismic measurements in a borehole. We first develop ...

  11. How can we use one fracture to locate another?

    E-Print Network [OSTI]

    Poliannikov, Oleg V.

    2011-01-01

    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 ...

  12. On equivalence of thinning fluids used for hydraulic fracturing

    E-Print Network [OSTI]

    Linkov, Alexander

    2012-01-01

    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...

  13. Hydraulic Fracture Monitoring: A Jonah Field Case Study

    E-Print Network [OSTI]

    Seher, T.

    2011-01-01

    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 ...

  14. Fracture Characterization from Scattered Energy: A Case Study

    E-Print Network [OSTI]

    Grandi, Samantha K.

    2006-01-01

    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. ...

  15. Streamline-based production data integration in naturally fractured reservoirs 

    E-Print Network [OSTI]

    Al Harbi, Mishal H.

    2005-08-29

    dualporosity streamline model for fracture flow simulation by treating the fracture and matrix as separate continua that are connected through a transfer function. Next, we analytically compute the sensitivities that define the relationship between...

  16. Geomechanical Development of Fractured Reservoirs During Gas Production 

    E-Print Network [OSTI]

    Huang, Jian

    2013-04-05

    Within fractured reservoirs, such as tight gas reservoir, coupled processes between matrix deformation and fluid flow are very important for predicting reservoir behavior, pore pressure evolution and fracture closure. To study the coupling between...

  17. Analysis of Scattered Signal to Estimate Reservoir Fracture Parameters

    E-Print Network [OSTI]

    Grandi, Samantha K.

    We detect fracture corridors and determine their orientation and average spacing based on an analysis of seismic coda in the frequency-wave number (f-k ) domain. Fracture corridors have dimensions similar to seismic ...

  18. A Bayesian framework for fracture characterization from surface seismic data

    E-Print Network [OSTI]

    Zamanian, S. Ahmad

    2012-01-01

    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 ...

  19. Seismic characterization of fractured reservoirs by focusing Gaussian beams

    E-Print Network [OSTI]

    Zheng, Yingcai

    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 ...

  20. Finite Difference Modeling of Seismic Responses to Intersecting Fracture Sets

    E-Print Network [OSTI]

    Chi, Shihong

    2006-01-01

    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 ...

  1. Effects of subsurface fracture interactions on surface deformation

    E-Print Network [OSTI]

    Jerry, Ruel (Ruel Valentine)

    2013-01-01

    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 ...

  2. Simulated evolution of fractures and fracture networks subject to thermal cooling: A coupled discrete element and heat conduction model

    SciTech Connect (OSTI)

    Huang, Hai; Plummer, Mitchell; Podgorney, Robert

    2013-02-01

    Advancement of EGS requires improved prediction of fracture development and growth during reservoir stimulation and long-term operation. This, in turn, requires better understanding of the dynamics of the strongly coupled thermo-hydro-mechanical (THM) processes within fractured rocks. We have developed a physically based rock deformation and fracture propagation simulator by using a quasi-static discrete element model (DEM) to model mechanical rock deformation and fracture propagation induced by thermal stress and fluid pressure changes. We also developed a network model to simulate fluid flow and heat transport in both fractures and porous rock. In this paper, we describe results of simulations in which the DEM model and network flow & heat transport model are coupled together to provide realistic simulation of the changes of apertures and permeability of fractures and fracture networks induced by thermal cooling and fluid pressure changes within fractures. Various processes, such as Stokes flow in low velocity pores, convection-dominated heat transport in fractures, heat exchange between fluid-filled fractures and solid rock, heat conduction through low-permeability matrices and associated mechanical deformations are all incorporated into the coupled model. The effects of confining stresses, developing thermal stress and injection pressure on the permeability evolution of fracture and fracture networks are systematically investigated. Results are summarized in terms of implications for the development and evolution of fracture distribution during hydrofracturing and thermal stimulation for EGS.

  3. Fracture Toughness Prediction for MWCNT Reinforced Ceramics

    SciTech Connect (OSTI)

    Henager, Charles H.; Nguyen, Ba Nghiep

    2013-09-01

    This report describes the development of a micromechanics model to predict fracture toughness of multiwall carbon nanotube (MWCNT) reinforced ceramic composites to guide future experimental work for this project. The modeling work described in this report includes (i) prediction of elastic properties, (ii) development of a mechanistic damage model accounting for matrix cracking to predict the composite nonlinear stress/strain response to tensile loading to failure, and (iii) application of this damage model in a modified boundary layer (MBL) analysis using ABAQUS to predict fracture toughness and crack resistance behavior (R-curves) for ceramic materials containing MWCNTs at various volume fractions.

  4. MULTI-PHASE FRACTURE-MATRIX INTERACTIONS UNDER STRESS CHANGES

    SciTech Connect (OSTI)

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

    2005-06-15

    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 studied, 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.

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

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

    fabricate and test a downhole instrument for measuring fracture flow following a hydraulic stimulation experiment. reservoirrosetracerscharacterizefractures.pdf More...

  6. Estimation of fracture parameters from reflection seismic data - Part I ...

    E-Print Network [OSTI]

    A. Bakulin, V. Grechka, I. Tsvankin

    2000-11-02

    rocks requires accounting for the hydraulic interaction between cracks and pores. INTRODUCTION. Seismic detection of subsurface fractures has important ap-.

  7. Experimental and Analytical Research on Fracture Processes in ROck

    SciTech Connect (OSTI)

    Herbert H.. Einstein; Jay Miller; Bruno Silva

    2009-02-27

    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.

  8. Dynamic fracturing: eld and experimental observations Amir Sagy*, Ze'ev Reches, Itzhak Roman

    E-Print Network [OSTI]

    Ze'ev, Reches

    Dynamic fracturing: ®eld and experimental observations Amir Sagy*, Ze'ev Reches, Itzhak Roman three styles of fracturing: planar fractures, known from previous tests; branching fractures and clustering fractures, observed here for the ®rst time in layered composites. Based on fracture morphology, we

  9. Methodologies and new user interfaces to optimize hydraulic fracturing design and evaluate fracturing performance for gas wells 

    E-Print Network [OSTI]

    Wang, Wenxin

    2006-04-12

    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...

  10. 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

  11. The Transport of Nuclear Contamination in Fractured Porous Media

    E-Print Network [OSTI]

    Douglas Jr., Jim

    The Transport of Nuclear Contamination in Fractured Porous Media Jim Douglas, Jr. #3; Anna M and dispersion of nuclear contamination through a granitic medium having densely spaced fractures, Rochester, MI 48309-4485 1 #12; Nuclear Contamination in Fractured Porous Media 2 2 The Single Porosity

  12. Estimating Major and Minor Natural Fracture Patterns in Gas

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    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

  13. Creation and Impairment of Hydraulic Fracture Conductivity in Shale Formations 

    E-Print Network [OSTI]

    Zhang, Junjing

    2014-07-10

    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...

  14. 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

  15. 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

  16. Hydraulic Fractures: multiscale phenomena, asymptotic and numerical solutions

    E-Print Network [OSTI]

    Peirce, Anthony

    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

  17. Hydraulic Fractures: multiscale phenomena, asymptotic and numerical solutions

    E-Print Network [OSTI]

    Peirce, Anthony

    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

  18. Poroelastic modeling of seismic boundary conditions across a fracture

    E-Print Network [OSTI]

    2007-07-20

    Permeability of a fracture can affect how the fracture interacts with seismic waves. To examine this effect ... seismic wave scattering off nonplanar e.g., curved and intersecting fractures. ..... values, this can result in a significant error in evaluating the average fluid pressure .... As seen from the plot, the transition be- tween the ...

  19. Automatic Fracture Reduction Thomas Albrecht and Thomas Vetter

    E-Print Network [OSTI]

    Vetter, Thomas

    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

  20. 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

  1. 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

  2. Fibre Based Modeling of Wood Dynamics and Fracture

    E-Print Network [OSTI]

    Bridson, Robert

    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

  3. Fracture aperture reconstruction and determination of hydrological properties: a

    E-Print Network [OSTI]

    Toussaint, Renaud

    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

  4. In vitro fracture toughness of human dentin V. Imbeni,1

    E-Print Network [OSTI]

    Ritchie, Robert

    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

  5. Fracture Toughness of MDF and other Materials with Fiber Bridging

    E-Print Network [OSTI]

    Nairn, John A.

    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

  6. Fracture surface energy of the Punchbowl fault, San Andreas system

    E-Print Network [OSTI]

    Chester, Frederick M.

    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

  7. Fracture patterns in thin films and multilayers Alex A. Volinsky

    E-Print Network [OSTI]

    Volinsky, Alex A.

    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

  8. Meshfree Simulations of Spall Fracture By Bo Ren ,

    E-Print Network [OSTI]

    Li, Shaofan

    Meshfree Simulations of Spall Fracture By Bo Ren , , Shaofan Li, , Jing Qian , Xiaowei Zeng Shock wave induced spall fracture is a complex multiscale phenomenon, and it is a challenge to build a constitutive and computational model that can capture the essential features of the spall fracture

  9. Molecular dynamics study of fracture accompanied by chemical reaction

    E-Print Network [OSTI]

    Krivtsov, Anton M.

    Molecular dynamics study of fracture accompanied by chemical reaction Anton M. Krivtsov akrivtsov@bk.ru Abstract A molecular dynamics model for fracture accompanied by chemical reac- tion is suggested. Crack of the initial and new specimen surfaces during the fracture process is taken into account. It is pos- tulated

  10. Influence of defects distribution and specimen size on fracture initiation

    E-Print Network [OSTI]

    Krivtsov, Anton M.

    Influence of defects distribution and specimen size on fracture initiation Anton M. Krivtsov akrivtsov@bk.ru Abstract An analytical model for the scale dependence of the fracture initiation is suggested. The model is based on the idea that fracture is a stochastic process, for the bigger specimens

  11. Short communication Fractal in fracture of bulk metallic glass

    E-Print Network [OSTI]

    Gao, Jianbo

    Short communication Fractal in fracture of bulk metallic glass M.Q. Jiang a,b , J.X. Meng a , J. Bulk metallic glass B. Dynamic fracture C. Nanoscale periodic corrugation C. Fractal a b s t r a c t We investigate the nanoscale periodic corrugation (NPC) structures on the dynamic fracture surface of a typical

  12. A dimensional decomposition method for stochastic fracture mechanics

    E-Print Network [OSTI]

    Rahman, Sharif

    A dimensional decomposition method for stochastic fracture mechanics Sharif Rahman * Department required by the proposed method can be viewed as performing deterministic fracture analyses at selected, no derivatives of fracture response are required by the new method developed. Results of three numerical exam

  13. A Cohesive Approach to Thin-Shell Fracture and Fragmentation

    E-Print Network [OSTI]

    Cirak, Fehmi

    A Cohesive Approach to Thin-Shell Fracture and Fragmentation Fehmi Cirak1 , Michael Ortiz2 and Anna 20133 Milano, Italy Abstract We develop a finite-element method for the simulation of dynamic fracture and the fracture along the element edges is modeled with a cohesive law. In order to follow the prop- agation

  14. RESIDUAL STRESS EFFECTS IN FRACTURE OF COMPOSITES AND ADHESIVES

    E-Print Network [OSTI]

    Nairn, John A.

    RESIDUAL STRESS EFFECTS IN FRACTURE OF COMPOSITES AND ADHESIVES JOHN A. NAIRN ABSTRACT Because by including residual stresses in fracture mechanics models of failure. This chapter gives general results examples of including residual stresses in fracture mechanics interpretation of experimental results

  15. A unified enrichment scheme for fracture Safdar Abbas

    E-Print Network [OSTI]

    A unified enrichment scheme for fracture problems Safdar Abbas Thomas-Peter Fries AICES, RWTH XFEM in fracture mechanics Numerical examples (cohesionless cracks) Numerical examples (cohesive cracks) Conclusions Future outlook 2 #12;Motivation Outline Motivation XFEM in fracture mechanics Numerical examples

  16. Finite Element Model of Fracture Formation on Growing Surfaces

    E-Print Network [OSTI]

    Prusinkiewicz, Przemyslaw

    Finite Element Model of Fracture Formation on Growing Surfaces Pavol Federl and Przemyslaw-mail: federl|pwp@cpsc.ucalgary.ca Abstract We present a model of fracture formation on surfaces of bilayered materials. The model makes it possible to synthesize patterns of fractures induced by growth or shrinkage

  17. Analyzing and Simulating Fracture Patterns of Theran Wall Paintings

    E-Print Network [OSTI]

    Singh, Jaswinder Pal

    10 Analyzing and Simulating Fracture Patterns of Theran Wall Paintings HIJUNG SHIN, Princeton and Akrotiri Excavation TIM WEYRICH, University College London In this article, we analyze the fracture that suggests a hierarchical fracture pattern where fragments break into two pieces recursively along cracks

  18. Gaseous Detonation-Driven Fracture of Tubes Tong Wa Chao

    E-Print Network [OSTI]

    Barr, Al

    Gaseous Detonation-Driven Fracture of Tubes Thesis by Tong Wa Chao In Partial Fulfillment An experimental investigation of fracture response of aluminum 6061-T6 tubes under internal gaseous detonation of this particular traveling load and tube geometry produced fracture data not available before in the open

  19. Oil recovery enhancement from fractured, low permeability reservoirs. Annual report 1990--1991, Part 1

    SciTech Connect (OSTI)

    Poston, S.W.

    1991-12-31

    Joint funding by the Department of Energy and the State of Texas has Permitted a three year, multi-disciplinary investigation to enhance oil recovery from a dual porosity, fractured, low matrix permeability oil reservoir to be initiated. The Austin Chalk producing horizon trending thru the median of Texas has been identified as the candidate for analysis. Ultimate primary recovery of oil from the Austin Chalk is very low because of two major technological problems. The commercial oil producing rate is based on the wellbore encountering a significant number of natural fractures. The prediction of the location and frequency of natural fractures at any particular region in the subsurface is problematical at this time, unless extensive and expensive seismic work is conducted. A major portion of the oil remains in the low permeability matrix blocks after depletion because there are no methods currently available to the industry to mobilize this bypassed oil. The following multi-faceted study is aimed to develop new methods to increase oil and gas recovery from the Austin Chalk producing trend. These methods may involve new geological and geophysical interpretation methods, improved ways to study production decline curves or the application of a new enhanced oil recovery technique. The efforts for the second year may be summarized as one of coalescing the initial concepts developed during the initial phase to more in depth analyses. Accomplishments are predicting natural fractures; relating recovery to well-log signatures; development of the EOR imbibition process; mathematical modeling; and field test.

  20. Categorical Exclusion Determinations: Advanced Technology Vehicles...

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

    Group LLC, Revised Specific Project Application 2, Retooling, Reequipping and Engineering CX(s) Applied: B1.31, B5.1 Date: 09062011 Location(s): Auburn Hills, Michigan...

  1. Categorical Exclusion Determinations: National Energy Technology...

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

    August 27, 2014 CX-012437: Categorical Exclusion Determination High Energy Density Lithium Battery CX(s) Applied: B3.6 Date: 41878 Location(s): New York Offices(s): National...

  2. A Global Model for Fracture Falloff Analysis 

    E-Print Network [OSTI]

    Marongiu-Porcu, Matteo

    2014-10-29

    and estimate of the induced fracture geometry) as well as reservoir permeability and formation pressure, provided that enough time is allowed for the falloff to reach pseudo-radial flow regime. Both oil and gas reservoirs can be effectively studied. Another...

  3. Gas condensate damage in hydraulically fractured wells 

    E-Print Network [OSTI]

    Adeyeye, Adedeji Ayoola

    2004-09-30

    This project is a research into the effect of gas condensate damage in hydraulically fractured wells. It is the result of a problem encountered in producing a low permeability formation from a well in South Texas owned by the El Paso Production...

  4. Correlating toughness and roughness in ductile fracture

    E-Print Network [OSTI]

    Laurent Ponson; Ankit Srivastava; Shmulik Osovski; Elisabeth Bouchaud; Viggo Tvergaard; Alan Needleman

    2013-07-16

    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 correlation length of the fracture surface corresponding to the cut-off of the self-affine behavior is found to be linearly related to JIC thus quantitatively correlating toughness and fracture surface roughness.

  5. Interference Fracturing: Non-Uniform Distributions of Perforation Clusters that Promote Simultaneous Growth of Multiple Hydraulic Fractures

    E-Print Network [OSTI]

    Peirce, Anthony

    of Bunger et al. (In Press) is consistent with past observations of multiple hydraulic fracture growth from 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

  6. Interference Fracturing: Non-Uniform Distributions of Perforation Clusters that Promote Simultaneous Growth of Multiple Hydraulic Fractures

    E-Print Network [OSTI]

    Peirce, Anthony

    Simultaneous Growth of Multiple Hydraulic Fractures A.P. Peirce, University of British Columbia and A.P. Bunger hurdles in horizontal well stimulation is the generation of hydraulic fractures (HFs) from all perforation shadowing" that refers to suppression of some hydraulic fractures by the compressive stresses exerted

  7. Investigation of the influence of natural fractures and in situ stress on hydraulic fracture propagation using a

    E-Print Network [OSTI]

    ARTICLE Investigation of the influence of natural fractures and in situ stress on hydraulic: Hydraulic fracturing is the primary means for enhancing rock mass permeability and improving well productiv- ity in tight reservoir rocks. Significant advances have been made in hydraulic fracturing theory

  8. Natural Fracture Characterization by Source Mechanism Estimation and Semi-Stochastic Generation of Discrete Fracture Networks Using Microseismic and Core Data 

    E-Print Network [OSTI]

    Sotelo Gamboa, Edith

    2014-11-12

    The overall goal of this study is to generate discrete fracture networks using microseismic and core data from a natural fractured reservoir that has been hydraulically stimulated. To improve fracture characterization, a ...

  9. Advancing New 3D Seismic Interpretation Methods for Exploration and Development of Fractured Tight Gas Reservoirs

    SciTech Connect (OSTI)

    James Reeves

    2005-01-31

    In a study funded by the U.S. Department of Energy and GeoSpectrum, Inc., new P-wave 3D seismic interpretation methods to characterize fractured gas reservoirs are developed. A data driven exploratory approach is used to determine empirical relationships for reservoir properties. Fractures are predicted using seismic lineament mapping through a series of horizon and time slices in the reservoir zone. A seismic lineament is a linear feature seen in a slice through the seismic volume that has negligible vertical offset. We interpret that in regions of high seismic lineament density there is a greater likelihood of fractured reservoir. Seismic AVO attributes are developed to map brittle reservoir rock (low clay) and gas content. Brittle rocks are interpreted to be more fractured when seismic lineaments are present. The most important attribute developed in this study is the gas sensitive phase gradient (a new AVO attribute), as reservoir fractures may provide a plumbing system for both water and gas. Success is obtained when economic gas and oil discoveries are found. In a gas field previously plagued with poor drilling results, four new wells were spotted using the new methodology and recently drilled. The wells have estimated best of 12-months production indicators of 2106, 1652, 941, and 227 MCFGPD. The latter well was drilled in a region of swarming seismic lineaments but has poor gas sensitive phase gradient (AVO) and clay volume attributes. GeoSpectrum advised the unit operators that this location did not appear to have significant Lower Dakota gas before the well was drilled. The other three wells are considered good wells in this part of the basin and among the best wells in the area. These new drilling results have nearly doubled the gas production and the value of the field. The interpretation method is ready for commercialization and gas exploration and development. The new technology is adaptable to conventional lower cost 3D seismic surveys.

  10. Molecular basis of fracture in polystyrene films

    SciTech Connect (OSTI)

    Sambasivam, M.; Klein, A.; Thomas, T.N.; Mohammadi, N.; Sperling, L.H. [Lehigh Univ., Bethlehem, PA (United States)

    1993-12-31

    To understand the molecular mechanisms involved in the fracture of polystyrene films, a custom built dental burr grinding instrument was used. Films were made from latexes, compression molded polystyrene, and by photopolymerization. Latexes were prepared by direct miniemulsification of polystyrene using sodium lauryl sulfate as surfactant and cetyl and stearyl alcohols as co-surfactants. Grinding of various films was carried out at room temperature. GPC was used to determine the molecular weight before and after grinding. From the molecular weight reduction, the number of chain scissions per unit volume was determined. The energy required for the grinding process was also measured. The results are consistent with a model of exciting 300{+-}150 bonds (per chain fracture) to the breaking point. The most probable deformation mode, consuming maximum energy is envisaged as the scissor-like opening of the 109{degrees} -C-C-C bond angle.

  11. Correlating toughness and roughness in ductile fracture

    E-Print Network [OSTI]

    Ponson, Laurent; Osovski, Shmulik; Bouchaud, Elisabeth; Tvergaard, Viggo; Needleman, Alan

    2013-01-01

    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...

  12. Fracture simulation for zirconia toughened alumina microstructure

    E-Print Network [OSTI]

    Kim, Kyungmok; Forest, Bernard

    2013-01-01

    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...

  13. Laboratory testing of cement grouting of fractures in welded tuff

    SciTech Connect (OSTI)

    Sharpe, C.J.; Daemen, J.J.

    1991-03-01

    Fractures in the rock mass surrounding a repository and its shafts, access drifts, emplacement rooms and holes, and exploratory or in-situ testing holes, may provide preferential flowpaths for the flow of groundwater or air, potentially containing radionuclides. Such cracks may have to be sealed. The likelihood that extensive or at least local grouting will be required as part of repository sealing has been noted in numerous publications addressing high level waste repository closing. The objective of this work is to determine the effectiveness of fracture sealing (grouting) in welded tuff. Experimental work includes measurement of intact and fracture permeability under various normal stresses and injection pressures. Grout is injected into the fractures. The effectiveness of grouting is evaluated in terms of grout penetration and permeability reduction, compared prior to and after grouting. Analysis of the results include the effect of normal stress, injection pressure, fracture roughness, grout rheology, grout bonding, and the radial extent of grout penetration. Laboratory experiments have been performed on seventeen tuff cylinders with three types of fractures: (1) tension induced cracks, (2) natural fractures, and (3) sawcuts. Prior to grouting, the hydraulic conductivity of the intact rock and of the fractures is measured under a range of normal stresses. The surface topography of the fracture is mapped, and the results are used to determine aperture distributions across the fractures. 72 refs., 76 figs., 25 tabs.

  14. FRACTURE FAILURE CRITERIA OF SOFC PEN STRUCTURE

    SciTech Connect (OSTI)

    Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.; Qu, Jianmin

    2007-04-30

    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.

  15. Curvilinear gullies, lobate deposits and fractures, and their implications for the geologic evolution and hydration of Vesta

    E-Print Network [OSTI]

    Scully, Jennifer Eva

    2015-01-01

    and impact- induced fracturing, it has remained largelyof impact-induced fracturing in the northern hemisphere andand impact-induced fracturing throughout its history.

  16. Micromechanisms of ductile fracturing of DH-36 steel plates under impulsive loads and influence of polyurea reinforcing

    E-Print Network [OSTI]

    Amini, M. R.; Nemat-Nasser, S.

    2010-01-01

    Micromechanisms of ductile fracturing of DH-36 steel platesMicromechanisms of ductile fracturing of DH-36 steel platesundergoes controllable fracturing, generally initiated near

  17. FRACTURE MECHANISM OF A BAINITE STEEL IN PRECRACKED AND NOTCHED SPECIMENS

    E-Print Network [OSTI]

    Qin, Qinghua

    . KEYWORDS Fracture toughness, cleavage fracture, crack depth, ductile crack growth, bainite steel, fracture specimens fractured at lower-shelf region without any ductile crack growth. The critical crack tip opening there was an apparent improvement in fracture toughness (KIC) measured using precracked specimens but a decrease

  18. Mixed-mode fracture of human cortical bone Elizabeth A. Zimmermann a,b

    E-Print Network [OSTI]

    Ritchie, Robert

    Mixed-mode fracture of human cortical bone Elizabeth A. Zimmermann a,b , Maximilien E. Launey Available online 1 July 2009 Keywords: Human cortical bone Mixed-mode fracture Fracture toughness Fracture mechanisms a b s t r a c t Although the mode I (tensile opening) fracture toughness has been the focus

  19. Author's personal copy Calibration procedures for a computational model of ductile fracture

    E-Print Network [OSTI]

    Hutchinson, John W.

    Author's personal copy Calibration procedures for a computational model of ductile fracture Z. Xue fracture Computational fracture Shear fracture Damage parameters a b s t r a c t A recent extension of the cup-cone fracture mode in the neck of a round tensile bar. Ductility of a notched round bar provides

  20. Material Point Method Simulations of Transverse Fracture in Wood with Realistic Morphologies

    E-Print Network [OSTI]

    Nairn, John A.

    Material Point Method Simulations of Transverse Fracture in Wood with Realistic Morphologies By J Material point method Numerical modeling RT fracture TR fracture; Transverse fracture Summary A new used to simulate transverse fracture in solid wood. The simulations were run on the scale of growth

  1. Low temperature fracture evaluation of plasticized sulfur paving mixtures 

    E-Print Network [OSTI]

    Mahboub, Kamyar

    1985-01-01

    . Characterize the fracture behavior of sulphlex binders by using the elastic-plastic critical energy release rate, J C. 2. Approximate the fracture toughness of the material, KIC, by the KO parameter and establish a correlation between KO and JIC parameters... concentrations leading to failure of a structural component. The first analysis of fracture behavior of britt! e materials containing sharp flaws was developed by Griffith (16). He considered a very large plate with a sharp crack of length 2a passing...

  2. Faience Technology

    E-Print Network [OSTI]

    Nicholson, Paul

    2009-01-01

    by Joanne Hodges. Faience Technology, Nicholson, UEE 2009Egyptian materials and technology, ed. Paul T. Nicholson,Nicholson, 2009, Faience Technology. UEE. Full Citation:

  3. A Simple, Fast Method of Estimating Fractured Reservoir Geometry...

    Open Energy Info (EERE)

    Fractured Reservoir Geometry from Tracer Tests Abstract A simple method of estimating flow geometry and pore geometry from conservative tracer tests in single phase geothermal...

  4. Dispersed Fluid Flow in Fractured Reservoirs- an Analysis of...

    Open Energy Info (EERE)

    Dispersed Fluid Flow in Fractured Reservoirs- an Analysis of Tracer-Determined Residence Time Distributions Jump to: navigation, search OpenEI Reference LibraryAdd to library...

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

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

    Reservoirs Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs Project objectives: Improve image resolution for microseismicimaging and...

  6. Elastic properties of saturated porous rocks with aligned fractures

    E-Print Network [OSTI]

    2003-12-02

    of fluid properties on seismic characteristics. ... C. C. A . The host rock is permeated by a set of parallel fractures which are ..... Similar behaviour is ..... Page 14 ...

  7. Shale Gas Application in Hydraulic Fracturing Market is likely...

    Open Energy Info (EERE)

    on unconventional reservoirs such as coal bed methane, tight gas, tight oil, shale gas, and shale oil. Over the period of time, hydraulic fracturing technique has found...

  8. Seismic velocity and Q anisotropy in fractured poroelastic media

    E-Print Network [OSTI]

    A poroelastic medium with embedded aligned fractures exhibits significant attenuation and dispersion effects due to this mechanism, which can properly be

  9. Seismic velocity and Q anisotropy in fractured poroelastic media

    E-Print Network [OSTI]

    Juan E. Santos

    2014-05-29

    medium with embedded aligned fractures exhibits significant attenuation and dispersion effects due to this mechanism, which can properly be represented at the ...

  10. INJECTION AND THERMAL BREAKTHROUGH IN FRACTURED GEOTHERMAL RESERVOIRS

    E-Print Network [OSTI]

    Bodvarsson, Gudmundur S.

    2012-01-01

    and Pruess, K. , Analysis of injection testing of geothermalreservoirs: Geothermal Resoures Council, Vol. 4. , (into a fractured geothermal reservoir: Transactions, Vol. 4,

  11. Evaluation of subsurface fracture geometry using fluid pressure...

    Open Energy Info (EERE)

    Evaluation of subsurface fracture geometry using fluid pressure response to solid earth tidal strain Jump to: navigation, search OpenEI Reference LibraryAdd to library Report:...

  12. Integrated 3D Acid Fracturing Model for Carbonate Reservoir Stimulation 

    E-Print Network [OSTI]

    Wu, Xi

    2014-06-23

    and illustrates the application of the approach with examples. The results from this study show that the new model can successfully design and optimize acid fracturing treatments....

  13. Reservoir-Scale Fracture Permeability in the Dixie Valley, Nevada...

    Open Energy Info (EERE)

    Conference Paper: Reservoir-Scale Fracture Permeability in the Dixie Valley, Nevada, Geothermal Field Abstract Borehole televiewer, temperature, and flowmeter datarecorded in...

  14. Determination Of The Orientation Of Open Fractures From Hydrophone VSP

    E-Print Network [OSTI]

    Lee, Jung Mo

    1995-01-01

    Open fractures are of interest in many areas such as ground water contamination, hazardous waste disposal, oil and gas recovery, and geothermal energy extraction. In

  15. Carbon Dioxide Geological Sequestration in Fractured Porous Rocks

    Office of Scientific and Technical Information (OSTI)

    Training and Research on Probabilistic Hydro-Thermo-Mechanical Modeling of Carbon Dioxide Geological Sequestration in Fractured Porous Rocks Gutierrez, Marte 54 ENVIRONMENTAL...

  16. Studies of Transport Properties of Fractures: Final Report

    SciTech Connect (OSTI)

    Stephen R. Brown

    2006-06-30

    We proposed to study several key factors controlling the character and evolution of fracture system permeability and transport processes. We suggest that due to surface roughness and the consequent channeling in single fractures and in fracture intersections, the tendency of a fracture system to plug up, remain permeable, or for permeability to increase due to chemical dissolution/precipitation conditions will depend strongly on the instantaneous flow channel geometry. This geometry will change as chemical interaction occurs, thus changing the permeability through time. To test this hypothesis and advance further understanding toward a predictive capability, we endeavored to physically model and analyze several configurations of flow and transport of inert and chemically active fluids through channels in single fractures and through fracture intersections. This was an integrated program utilizing quantitative observations of fractures and veins in drill core, quantitative and visual observations of flow and chemical dissolution and precipitation within replicas of real rough-walled fractures and fracture intersections, and numerical modeling via lattice Boltzmann methods.

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

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

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

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

    Open Energy Info (EERE)

    rocks in order to better understand the fracturing system. - Utilize soft computing to process and analyze the passive seismic data. Awardees (Company Institution) University...

  19. Seepage into drifts in unsaturated fractured rock at Yucca Mountain

    E-Print Network [OSTI]

    Birkholzer, Jens; Li, Guomin; Tsang, Chin-Fu; Tsang, Yvonne

    1998-01-01

    Fractured Rock at Yucca Mountain Jens Birkholzer, Guomin Lrepository site at Yucca Mountain, Nevada, as it is locatedclimate conditions at Yucca Mountain. The numerical study is

  20. Scale-Dependent Fracture-Matrix Interactions and Their Impact...

    Office of Scientific and Technical Information (OSTI)

    Scale-Dependent Fracture-Matrix Interactions and Their Impact on Radionuclide Transport: Development of efficient particle-tracking methods Citation Details In-Document Search...

  1. Fracture Evolution Following a Hydraulic Stimulation within an...

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

    Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir presentation at the April 2013 peer review meeting held in Denver, Colorado. flowevolutionpeer2013.pd...

  2. Microseismicity, stress, and fracture in the Coso geothermal...

    Open Energy Info (EERE)

    Microseismicity, stress, and fracture in the Coso geothermal field, California Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Microseismicity,...

  3. Using supercritical carbon dioxide as a fracturing fluid

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

    and develop models to compare different working models of hydraulic fracturing for shale gas and oil production. Laboratory researchers have published a paper in Applied...

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

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

    Geothermal Field by Micro-seismic Data, Using Soft Computing, Fractals, and Shear Wave Anisotropy Characterizing Fractures in the Geysers Geothermal Field by Micro-seismic...

  5. Characterization of subsurface fracture patterns in the Coso...

    Open Energy Info (EERE)

    of subsurface fracture patterns in the Coso geothermal reservoir by analyzing shear-wave splitting of microearthquake seismorgrams Jump to: navigation, search OpenEI Reference...

  6. Characterization Of Fracture Patterns In The Geysers Geothermal...

    Open Energy Info (EERE)

    Characterization Of Fracture Patterns In The Geysers Geothermal Reservoir By Shear-Wave Splitting Jump to: navigation, search OpenEI Reference LibraryAdd to library Report:...

  7. Finding Large Aperture Fractures in Geothermal Resource Areas...

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

    Seismic Survey DOE Geothermal Peer Review 2010 - Presentation. Project summary: Drilling into large aperture open fractures (LAFs) typically yield production wells with...

  8. Identification of MHF Fracture Planes and Flow Paths- a Correlation...

    Open Energy Info (EERE)

    creation of flow paths through the rock between two wellbores. To date, circulation systems have only been created by drilling one wellbore, hydraulically fracturing the well...

  9. Finding Large Aperture Fractures in Geothermal Resource Areas...

    Open Energy Info (EERE)

    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....

  10. Finite-element harmonic experiments to model fractured induced ...

    E-Print Network [OSTI]

    santos

    Mar 10, 2014 ... Fractured hydrocarbon reservoirs have been the subject of interest in explo- ... since these factors control hydrocarbon production [2]. This is ...

  11. Variational fracture mechanics The fracture pattern in stressed bodies is defined through the minimization of a two-field pseudo-spatial-

    E-Print Network [OSTI]

    Segatti, Antonio

    Variational fracture mechanics The fracture pattern in stressed bodies is defined through-deviatoric and masonry-like fractures. Remarkably, this latter formulation rigorously avoid material overlapping., Francfort, G. A. and J. J. Marigo, Numerical experiments in revisited brittle fracture. J. Mech. Phys

  12. Seismic scattering attributes to estimate reservoir fracture density : a numerical modeling study

    E-Print Network [OSTI]

    Pearce, Frederick D. (Frederick Douglas), 1978-

    2003-01-01

    We use a 3-D finite difference numerical model to generate synthetic seismograms from a simple fractured reservoir containing evenly-spaced, discrete, vertical fracture zones. The fracture zones are represented using a ...

  13. Analyzing Aqueous Solution Imbibition into Shale and the Effects of Optimizing Critical Fracturing Fluid Additives 

    E-Print Network [OSTI]

    Plamin, Sammazo Jean-bertrand

    2013-09-29

    Two methods of hydraulic fracturing most widely utilized on unconventional shale gas and oil reservoirs are “gelled fracturing” and “slick-water fracturing”. Both methods utilize up to several million gallons of water-based fluid per well in a...

  14. Analizing Aqueous Imbibition into Shale and the Effects of Optimizing Critical Fracturing Fluid Additives 

    E-Print Network [OSTI]

    Qureshi, Maha

    2013-09-29

    Two methods of hydraulic fracturing most widely utilized on unconventional shale gas and oil reservoirs are “gelled fracturing” and “slick-water fracturing”. Both methods utilize up to several million gallons of water-based fluid per well in a...

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

    E-Print Network [OSTI]

    Nelson, J.T.

    2009-01-01

    Motion for a New Model of Hydraulic Fracture With an Induced1987. Hydrodynamics of a Vertical Hydraulic Fracture, Earthand Fluid Flow in the Hydraulic Fracture Pmess, (PhD.

  16. Effects of non-Darcy flow on pressure buildup analysis of hydraulically fractured gas reservoirs 

    E-Print Network [OSTI]

    Alvarez Vera, Cesar

    2001-01-01

    Conventional well-testing techniques are commonly used to evaluate pressure transient tests of hydraulically fractured wells to estimate values such as formation permeability, fracture length, and fracture conductivity. When non-Darcy flow occurs...

  17. The Influence of Vertical Location on Hydraulic Fracture Conductivity in the Fayetteville Shale 

    E-Print Network [OSTI]

    Briggs, Kathryn

    2014-05-05

    Hydraulic fracturing is the primary stimulation method within low permeability reservoirs, in particular shale reservoirs. Hydraulic fracturing provides a means for making shale reservoirs commercially viable by inducing and propping fracture...

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

    E-Print Network [OSTI]

    Li, Yingping

    1996-01-01

    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 ...

  19. Hydraulic Fracture Optimization with a Pseudo-3D Model in Multi-layered Lithology 

    E-Print Network [OSTI]

    Yang, Mei

    2011-10-21

    Hydraulic Fracturing is a technique to accelerate production and enhance ultimate recovery of oil and gas while fracture geometry is an important aspect in hydraulic fracturing design and optimization. Systematic design procedures are available...

  20. On the fracture toughness of ferroelectric ceramics with electric field applied parallel to the crack front

    E-Print Network [OSTI]

    On the fracture toughness of ferroelectric ceramics with electric field applied parallel crack growth. The effects of electric field on the fracture toughness of both initially unpoled and poled materials are investigated. Results for the predicted fracture toughness, remanent strain

  1. Fractured Processes: Adaptive, Fine-Grained Process Abstractions Thanumalayan Sankaranarayana Pillai

    E-Print Network [OSTI]

    Swift, Michael

    Fractured Processes: Adaptive, Fine-Grained Process Abstractions Thanumalayan Sankaranarayana. Arpaci-Dusseau University of Wisconsin-Madison Abstract. We introduce Fracture, a novel framework that transforms and modernizes the basic process ab- straction. By "fracturing" an application into logical

  2. Theoretical and Numerical Simulation of Non-Newtonian Fluid Flow in Propped Fractures 

    E-Print Network [OSTI]

    Ouyang, Liangchen

    2013-12-10

    The flow of non-Newtonian fluids in porous media is important in many applications, such as polymer processing, heavy oil flow, and gel cleanup in propped fractures. Residual polymer gel in propped fractures results in low fracture conductivity...

  3. A Materials Science Driven Pattern Generation Solution to Fracturing Computer Generated Glass for Films and Games 

    E-Print Network [OSTI]

    Monroe, David Charles

    2014-08-11

    fracture patterns used for breaking objects apart based on input values, materials science literature, and fracture mechanics. After determining all of the fracture pattern variables such as the number of radial and concentric cracks, the artist is able...

  4. Stochastic multiscale fracture analysis of three-dimensional functionally graded composites

    E-Print Network [OSTI]

    Rahman, Sharif

    Stochastic multiscale fracture analysis of three-dimensional functionally graded composites Sharif: Probabilistic fracture mechanics Polynomial dimensional decomposition Random microstructure Reliability a b for stochastic multiscale fracture analysis of three-dimensional, particle-matrix, functionally graded materials

  5. Seismic Scattering Attributes to Estimate Reservoir Fracture Density: A Numerical Modeling Study

    E-Print Network [OSTI]

    Pearce, Frederick Douglas

    We use a 3-D finite difference numerical model to generate synthetic seismograms from a simple fractured reservoir containing evenly-spaced, discrete, vertical fracture zones. The fracture zones are represented using a ...

  6. Statistical analysis of surface lineaments and fractures for characterizing naturally fractured reservoirs

    SciTech Connect (OSTI)

    Guo, Genliang; George, S.A.; Lindsey, R.P.

    1997-08-01

    Thirty-six sets of surface lineaments and fractures mapped from satellite images and/or aerial photos from parts of the Mid-continent and Colorado Plateau regions were collected, digitized, and statistically analyzed in order to obtain the probability distribution functions of natural fractures for characterizing naturally fractured reservoirs. The orientations and lengths of the surface linear features were calculated using the digitized coordinates of the two end points of each individual linear feature. The spacing data of the surface linear features within an individual set were, obtained using a new analytical sampling technique. Statistical analyses were then performed to find the best-fit probability distribution functions for the orientation, length, and spacing of each data set. Twenty-five hypothesized probability distribution functions were used to fit each data set. A chi-square goodness-of-fit test was used to rank the significance of each fit. A distribution which provides the lowest chi-square goodness-of-fit value was considered the best-fit distribution. The orientations of surface linear features were best-fitted by triangular, normal, or logistic distributions; the lengths were best-fitted by PearsonVI, PearsonV, lognormal2, or extreme-value distributions; and the spacing data were best-fitted by lognormal2, PearsonVI, or lognormal distributions. These probability functions can be used to stochastically characterize naturally fractured reservoirs.

  7. Evaluation of acid fracturing based on the "acid fracture number" concept 

    E-Print Network [OSTI]

    Alghamdi, Abdulwahab

    2006-08-16

    Acid fracturing is one of the preferred methods to stimulate wells in carbonate reservoirs. It consists of injecting an acid solution at high enough pressure to break down the formation and to propagate a two-wing crack away from the wellbore...

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

    E-Print Network [OSTI]

    Marpaung, Fivman

    2009-05-15

    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...

  9. Hydraulic Fracturing | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar2-0057-EA JumpDuimen RiverScoringUtilities Comm Jump to: navigation,Fracturing

  10. Analytical modeling of a fracture-injection/falloff sequence and the development of a refracture-candidate diagnostic test 

    E-Print Network [OSTI]

    Craig, David Paul

    2006-08-16

    falloff data. To remove the current limitations, new analytical fractureinjection/ falloff models are developed that account for fracture propagation, fracture closure, and after fracture closure diffusion. A fracture-injection/falloff differs from a...

  11. Minimizing damage to a propped fracture by correct selection of proppant and controlled flowback procedures 

    E-Print Network [OSTI]

    Robinson, Bradley Mason

    1986-01-01

    of vertically fractured wells prior to stabilized flow . Areas of possible damage after a fracture treatment . . 13 The effects of damage on productivity index ratio, J/Jo 15 Fracture conductivity for different proppants - steel plate data 18 Fracture... . In general, one must consider the effects of the formation on the proppant due to fracture closure pressure, as well as the effects of the fracturing fluid and proppant on the reservoir. The strength of a proppant will determine its ability to withstand...

  12. Proppant Fracture Conductivity with High Proppant Loading and High Closure Stress 

    E-Print Network [OSTI]

    Rivers, Matthew Charles

    2011-08-08

    conditions. Proppant performance and fracture fluids, which carry the proppant into the fracture, and their subsequent clean-up during production, were studied. High strength proppant is ideal for deep fracture stimulations and in this study different... proppant loadings at different stresses were tested to see the impact of crushing and fracture width reduction on fracture conductivity. The preliminary test results indicated that oil at reservoir conditions improves clean-up of fracture fluid left...

  13. Summary of three dimensional pump testing of a fractured rock aquifer in the western Siberian Basin

    SciTech Connect (OSTI)

    Nichols, R.L.; Looney, B.B.; Eddy-Dilek, C.A.; Drozhko, E.G.; Glalolenko, Y.V.; Mokrov, Y.G.; Ivanov, I.A.; Glagolev, A.V.; Vasil`kova, N.A.

    1996-10-30

    A group of scientists from the Savannah River Technology Center and Russia successfully completed a 17 day field investigation of a fractured rock aquifer at the MAYAK PA nuclear production facility in Russia. The test site is located in the western Siberian Basin near the floodplain of the Mishelyak river. The fractured rock aquifer is composed of orphyrites, tuff, tuffbreccia and lava and is overlain by 0.5--12 meters of elluvial and alluvial sediments. A network of 3 uncased wells (176, 1/96, and 2/96) was used to conduct the tests. Wells 176 and 2/96 were used as observation wells and the centrally located well 1/96 was used as the pumping well. Six packers were installed and inflated in each of the observation wells at a depth of up to 85 meters. The use of 6 packers in each well resulted in isolating 7 zones for monitoring. The packers were inflated to different pressures to accommodate the increasing hydrostatic pressure. A straddle packer assembly was installed in the pumping well to allow testing of each of the individual zones isolated in the observation wells. A constant rate pumping test was run on each of the 7 zones. The results of the pumping tests are included in Appendix A. The test provided new information about the nature of the fractured rock aquifers in the vicinity of the Mishelyak river and will be key information in understanding the behavior of contaminants originating from process wastes discharged to Lake Karachi. Results from the tests will be analyzed to determine the hydraulic properties of different zones within the fractured rock aquifer and to determine the most cost effective clean-up approach for the site.

  14. In situ stress, fracture, and fluid flow analysis in Well 38C...

    Open Energy Info (EERE)

    wellbore image data, natural fracture characterization, and wellbore failure analysis. A hydraulic fracturing stress test at 3,703 feet TVD was used to constrain a normal faulting...

  15. IN SITU STRESS, FRACTURE, AND FLUID FLOW ANALYSIS IN WELL 38C...

    Open Energy Info (EERE)

    wellbore image data, natural fracture characterization, and wellbore failure analysis. A hydraulic fracturing stress test at 3,703 feet TVD was used to constrain a normal faulting...

  16. Fracturing Rigid Materials Zhaosheng Bao, Student Member, IEEE, Jeong-Mo Hong, Member, IEEE,

    E-Print Network [OSTI]

    Varadarajan, Veeravalli S.

    . Index Terms--Fracture, rigid bodies, finite element analysis. Ç 1 INTRODUCTION WETHER blowing up buildings, shattering glass, or destroying spaceships, fracture is ubiquitous in the movie industry

  17. The Effect of Connection Fractures on Steel Moment Resisting Frame

    E-Print Network [OSTI]

    Sweetman, Bert

    The Effect of Connection Fractures on Steel Moment Resisting Frame Seismic Demands and Safety - The Effect of Connection Fractures on SMRF Seismic Demands and Safety 1. Contents, Approach, Models........................................................................................C-1 "Numerical Example of the Proposed SAC Procedure for Assessing the Annual Exceedance Probabilities

  18. Laboratory studies of radionuclide transport in fractured Climax granite

    SciTech Connect (OSTI)

    Failor, R.; Isherwood, D.; Raber, E.; Vandergraaf, T.

    1982-06-01

    This report documents our laboratory studies of radionuclide transport in fractured granite cores. To simulate natural conditions, our laboratory studies used naturally fractured cores and natural ground water from the Climax Granite Stock at the Nevada Test Site. For comparison, additional tests used artificially fractured granite cores or distilled water. Relative to the flow of tritiated water, {sup 85}Sr and /sup 95m/Tc showed little or no retardation, whereas {sup 137}Cs was retarded. After the transport runs the cores retained varying amounts of the injected radionuclides along the fracture. Autoradiography revealed some correlation between sorption and the fracture fill material. Strontium and cesium retention increased when the change was made from natural ground water to distilled water. Artificial fractures retained less {sup 137}Cs than most natural fractures. Estimated fracture apertures from 18 to 60 {mu}m and hydraulic conductivities from 1.7 to 26 x 10{sup -3} m/s were calculated from the core measurements.

  19. Finessing the fracture energy barrier in ballistic seed dispersal

    E-Print Network [OSTI]

    Deegan, Robert

    is accomplished by a fast moving crack. However, cracks consume energy and should thus significantly degradeFinessing the fracture energy barrier in ballistic seed dispersal Robert D. Deegan1 Department December 1, 2011) Fracture is a highly dissipative process in which much of the stored elastic energy

  20. Identifying fracture zones in the Austin Chalk using seismic attributes 

    E-Print Network [OSTI]

    Bafia, Daniel Joseph

    1998-01-01

    . After studying various attributes, it was determined that there is no direct evidence of these fracture zones, but areas that are more prone to fracturing can be deduced from lithology. "Clean chalk, or areas that lack shale interbeds, is more brittle...

  1. Colloid-facilitated radionuclide transport in fractured porous rock 

    E-Print Network [OSTI]

    Baek, Inseok

    1994-01-01

    phase, a carrier phase, and a stationary solid phase. In the basic model, one-dimensional advection in a single planar fracture of infinite extent is coupled with diffusion in the rock matrix perpendicular to the fracture. In this study, a full...

  2. Truth and Lies About Hydraulic Fracturing By Terry Engelder

    E-Print Network [OSTI]

    Engelder, Terry

    of the global pushback against hydraulic fracturing, commonly known as "fracking." This came as no surprise attention. At that time the term "fracing" or "fracking," was not part of the English language; within two fracturing, and most people now know what "fracking" is. In Europe, I was frequently asked, "How can you

  3. Studying Hydraulic Fracturing through Time-variant Seismic Anisotropy 

    E-Print Network [OSTI]

    Liu, Qifan

    2013-10-01

    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...

  4. FATIGUE AND FRACTURE BEHAVIOR OF HIGH TEMPERATURE MATERIALS

    E-Print Network [OSTI]

    Ritchie, Robert

    toughness (R- In an attempt to enhance the ductility and fracture toughness of curve) and fatigue, they are plagued by poor ductility and toughness candidate material which could be used at significantly higher of the silicidesis severelylimited by their low ductility and poor fracture relatively ductile Mo phase

  5. A Numerical Investigation of Fault Slip Triggered by Hydraulic Fracturing

    E-Print Network [OSTI]

    through hydraulic fracturing, enhanced geothermal systems, or carbon dioxide (CO2) sequestration offers a means to understand the complex hydromechanical behavior of shale gas and oil reservoir systems the discontinuum-based distinct-element program UDEC assuming a fracture flow system. The conceptual reservoir

  6. Fractured reservoirs: An analysis of coupled elastodynamic and ...

    E-Print Network [OSTI]

    Daley, T., Schoenberg, M., Rutqvist, J., and Nihei, K.

    2006-08-28

    Aug 28, 2006 ... gate the effects of cracks and fractures on seismic wave propagation. (O'Connell .... (or decrease) elastodynamic compliance and fluid permeability. However .... 0.9 darcy. These values are within the range of fractured rocks see .... Full CMP analysis would require calcu- .... ments will test these approaches.

  7. The imbibition process of waterflooding in naturally fractured reservoirs 

    E-Print Network [OSTI]

    Huapaya Lopez, Christian A.

    2005-02-17

    -1 THE IMBIBITION PROCESS OF WATERFLOODING IN NATURALLY FRACTURED RESERVOIRS A Thesis by CHRISTIAN HUAPAYA LOPEZ 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 2003 Major Subject: Petroleum Engineering ii THE IMBIBITION PROCESS OF WATERFLOODING IN NATURALLY FRACTURED RESERVOIRS A Thesis by CHRISTIAN HUAPAYA LOPEZ...

  8. Seismic characterization of fractures Jos M. Carcione, OGS, Italy

    E-Print Network [OSTI]

    Santos, Juan

    Seismic characterization of fractures José M. Carcione, OGS, Italy Fractured geological formations is related to the orientation of the symmetry axis with respect to the direction of the seismic profile. We) generalized to the 3D case will be performed to compute surface seismic and VSP responses (Bakulin et al, 2000

  9. Seismic response of fractures and induced anisotropy in poroelastic media

    E-Print Network [OSTI]

    Santos, Juan

    Seismic response of fractures and induced anisotropy in poroelastic media Juan E. Santos Instituto) and R. Mart´inez Corredor (UNLP) Department of Mathematics, University of Calgary, October 2014 Seismic and angular variations of velocity and attenuation of seismic waves. Seismic response of fractures and induced

  10. Seismic response of fractures and induced anisotropy in poroelastic media

    E-Print Network [OSTI]

    Santos, Juan

    Seismic response of fractures and induced anisotropy in poroelastic media Juan E. Santos stituto) and R. Mart´inez Corredor (UNLP) Department of Mathematics, University of Calgary, October 2014 Seismic variations of velocity and attenuation of seismic waves. Seismic response of fractures and induced anisotropy

  11. Reactor Material Program Fracture Toughness of Type 304 Stainless Steel

    SciTech Connect (OSTI)

    Awadalla, N.G.

    2001-03-28

    This report describes the experimental procedure for Type 304 Stainless Steel fracture toughness measurements and the application of results. Typical toughness values are given based on the completed test program for the Reactor Materials Program (RMP). Test specimen size effects and limitations of the applicability in the fracture mechanics methodology are outlined as well as a brief discussion on irradiation effects.

  12. Spin and transverse momentum dependent Fracture Function in SIDIS

    E-Print Network [OSTI]

    A. Kotzinian; M. Anselmino; V. Barone

    2013-03-11

    The recently developed leading twist formalism for spin and transverse-momentum dependent fracture functions is shortly described. We demonstrate that the process of double hadron production in polarized SIDIS -- with one spinless hadron produced in the current fragmentation region (CFR) and another in the target fragmentation region (TFR) -- would provide access to all 16 leading twist fracture functions. Some particular cases are presented.

  13. Fracture Processes Observed with A Cryogenic Detector

    E-Print Network [OSTI]

    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

    2006-03-21

    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 .

  14. Enhanced Geothermal Systems Technologies

    Broader source: Energy.gov [DOE]

    Geothermal Energy an?d the Enhanced Geothermal Systems Concept The Navy 1 geothermal power plant near Coso Hot Springs, California, is applying EGS technology. Heat is naturally present everywhere in the earth. For all intents and purposes, heat from the earth is inexhaustible. Water is not nearly as ubiquitous in the earth as heat. Most aqueous fluids are derived from surface waters that have percolated into the earth along permeable pathways such as faults. Permeability is a measure of the ease of fluid flow through rock. The permeability of rock results from pores, fractures, joints, faults, and other openings which allow fluids to move. High permeability implies that fluids can flow rapidly through the rock. Permeability and, subsequently, the amount of fluids tend to decrease with depth as openings in the rocks compress from the weight of the overburden.

  15. Evaluation and significance of fracture toughness in ceramic materials

    SciTech Connect (OSTI)

    Mutoh, Y.

    1995-12-31

    Fracture toughness tests of several ceramic materials were carried out according to the various test methods, that is the Bridge indentation (BI, SEPB), Fatigue precrack (FP), Controlled surface flaw (CSF), Chevron notch (CN) and Indentation fracture (IF) methods. Mutual comparison of the test results was made to discuss the validity and applicability of each test method. Significance of the apparent fracture toughness with stable crack growth was discussed. The intrinsic fracture toughness can be obtained by the CSF method, in which a small surface crack is used. At high temperatures, since nonlinear deformation due to softening of glass phase and stable crack growth occur, nonlinear fracture mechanics approach should be applied. J{sub IC}-value is successfully evaluated according to the R-curve method.

  16. From invasion percolation to flow in rock fracture networks

    E-Print Network [OSTI]

    Wettstein, Salomon J; Araujo, Nuno A M; Lanyon, Bill; Herrmann, Hans J

    2011-01-01

    The main purpose of this work is to simulate two-phase flow in the form of immiscible displacement through anisotropic, three-dimensional (3D) discrete fracture networks (DFN). The considered DFNs are artificially generated, based on a general distribution function or are conditioned on measured data from deep geological investigations. We introduce several modifications to the invasion percolation (MIP) to incorporate fracture inclinations, intersection lines, as well as the hydraulic path length inside the fractures. Additionally a trapping algorithm is implemented that forbids any advance of the invading fluid into a region, where the defending fluid is completely encircled by the invader and has no escape route. We study invasion, saturation, and flow through artificial fracture networks, with varying anisotropy and size and finally compare our findings to well studied, conditioned fracture networks.

  17. Multiscale model reduction for shale gas transport in fractured media

    E-Print Network [OSTI]

    Akkutlu, I Y; Vasilyeva, Maria

    2015-01-01

    In this paper, we develop a multiscale model reduction technique that describes shale gas transport in fractured media. Due to the pore-scale heterogeneities and processes, we use upscaled models to describe the matrix. We follow our previous work \\cite{aes14}, where we derived an upscaled model in the form of generalized nonlinear diffusion model to describe the effects of kerogen. To model the interaction between the matrix and the fractures, we use Generalized Multiscale Finite Element Method. In this approach, the matrix and the fracture interaction is modeled via local multiscale basis functions. We developed the GMsFEM and applied for linear flows with horizontal or vertical fracture orientations on a Cartesian fine grid. In this paper, we consider arbitrary fracture orientations and use triangular fine grid and developed GMsFEM for nonlinear flows. Moreover, we develop online basis function strategies to adaptively improve the convergence. The number of multiscale basis functions in each coarse region ...

  18. Expansion of decline curve parameters for tight gas sands with massive hydraulic fractures

    SciTech Connect (OSTI)

    Schaefer, T.

    1995-12-31

    With the advances in modern hydrocarbon technology and expansion of geologic settings for development, it is necessary to make changes to the conventional wisdoms that accompany production technology. This paper discusses some possible changes that necessitate implementation as observed both empirically and analytically. Specifically it discusses the time at which a decline curve can be implemented for production forecasting, the need for a dual decline model, and the severity of the decline variable that may be used for this model. It is the point of this paper to prove that for fight gas sands with massive hydraulic fractures that it is not only feasible to use decline variables that are greater than the traditional limit of harmonic or 1.0, but that the decline curve may also be implemented in the transient flow period of the well and decline both hyperbolically and exponentially. These ideas were not only proven through field study, but were additionally modeled with a fracture flow simulator. In order to prove these points this paper first introduces the Red Fork Formation and the development of an initial field model curve for this formation. After the initial model was developed, questions arose as to its feasibility. These questions were first addressed with a literature survey and further comparisons were made to test the models accuracy using pressure decline analysis and a fracture flow simulator. All of these methods were used to justify the implementation of a decline exponent as high as 2.1 for a hyperbolic curve during the early transient flow period, and regressing this hyperbolic into an exponential decline in the pseudo-steady state period.

  19. Characterization of EGS Fracture Network Lifecycles

    SciTech Connect (OSTI)

    Gillian R. Foulger

    2008-03-31

    Geothermal energy is relatively clean, and is an important non-hydrocarbon source of energy. It can potentially reduce our dependence on fossil fuels and contribute to reduction in carbon emissions. High-temperature geothermal areas can be used for electricity generation if they contain permeable reservoirs of hot water or steam that can be extracted. The biggest challenge to achieving the full potential of the nation’s resources of this kind is maintaining and creating the fracture networks required for the circulation, heating, and extraction of hot fluids. The fundamental objective of the present research was to understand how fracture networks are created in hydraulic borehole injection experiments, and how they subsequently evolve. When high-pressure fluids are injected into boreholes in geothermal areas, they flow into hot rock at depth inducing thermal cracking and activating critically stressed pre-existing faults. This causes earthquake activity which, if monitored, can provide information on the locations of the cracks formed, their time-development and the type of cracking underway, e.g., whether shear movement on faults occurred or whether cracks opened up. Ultimately it may be possible to monitor the critical earthquake parameters in near-real-time so the information can be used to guide the hydraulic injection while it is in progress, e.g., how to adjust factors such as injectate pressure, volume and temperature. In order to achieve this, it is necessary to mature analysis techniques and software that were, at the start of this project, in an embryonic developmental state. Task 1 of the present project was to develop state-of-the-art techniques and software for calculating highly accurate earthquake locations, earthquake source mechanisms (moment tensors) and temporal changes in reservoir structure. Task 2 was to apply the new techniques to hydrofracturing (Enhanced Geothermal Systems, or “EGS”) experiments performed at the Coso geothermal field, in order to enhance productivity there. Task 3 was to interpret the results jointly with other geological information in order to provide a consistent physical model. All of the original goals of the project have been achieved. An existing program for calculating accurate relative earthquake locations has been enhanced by a technique to improve the accuracy of earthquake arrival-time measurements using waveform cross-correlation. Error analysis has been added to pre-existing moment tensor software. New seismic tomography software has been written to calculate changes in structure that could be due, for example, to reservoir depletion. Data processing procedures have been streamlined and web tools developed for rapid dissemination of the results, e.g., to on-site operations staff. Application of the new analysis tools to the Coso geothermal field has demonstrated the effective use of the techniques and provided important case histories to guide the style of future applications. Changes in reservoir structure with time are imaged throughout the upper 3 km, identifying the areas where large volumes of fluid are being extracted. EGS hydrofracturing experiments in two wells stimulated a nearby fault to the south that ruptured from south to north. The position of this fault could be precisely mapped and its existence was confirmed by surface mapping and data from a borehole televiewer log. No earthquakes occurred far north of the injection wells, suggesting that the wells lie near the northern boundary of the region of critically stressed faults. Minor en-echelon faults were also activated. Significant across-strike fluid flow occurred. The faults activated had significant crack-opening components, indicating that the hydraulic fracturing created open cavities at depth. The fluid injection changed the local stress field orientation and thus the mode of failure was different from the normal background. Initial indications are that the injections modulated stress release, seismicity and natural fracture system evolution for periods of up to months. The research demon

  20. Fracture toughness for copper oxide superconductors

    DOE Patents [OSTI]

    Goretta, Kenneth C. (Downers Grove, IL); Kullberg, Marc L. (Lisle, IL)

    1993-01-01

    An oxide-based strengthening and toughening agent, such as tetragonal Zro.sub.2 particles, has been added to copper oxide superconductors, such as superconducting YBa.sub.2 Cu.sub.3 O.sub.x (123) to improve its fracture toughness (K.sub.IC). A sol-gel coating which is non-reactive with the superconductor, such as Y.sub.2 BaCuO.sub.5 (211) on the ZrO.sub.2 particles minimized the deleterious reactions between the superconductor and the toughening agent dispersed therethrough. Addition of 20 mole percent ZrO.sub.2 coated with 211 yielded a 123 composite with a K.sub.IC of 4.5 MPa(m).sup.0.5.

  1. Fracture toughness for copper oxide superconductors

    DOE Patents [OSTI]

    Goretta, K.C.; Kullberg, M.L.

    1993-04-13

    An oxide-based strengthening and toughening agent, such as tetragonal ZrO[sub 2] particles, has been added to copper oxide superconductors, such as superconducting YBa[sub 2]Cu[sub 3]O[sub x] (123) to improve its fracture toughness (K[sub IC]). A sol-gel coating which is non-reactive with the superconductor, such as Y[sub 2]BaCuO[sub 5] (211) on the ZrO[sub 2] particles minimized the deleterious reactions between the superconductor and the toughening agent dispersed therethrough. Addition of 20 mole percent ZrO[sub 2] coated with 211 yielded a 123 composite with a K[sub IC] of 4.5 MPa(m)[sup 0.5].

  2. Advances in crack-arrest technology for reactor pressure vessels

    SciTech Connect (OSTI)

    Bass, B.R.; Pugh, C.E.

    1988-01-01

    The Heavy-Section Steel Technology (HSST) Program at the Oak Ridge National Laboratory (ORNL) under the sponsorship of the US Nuclear Regulatory Commission is continuing to improve the understanding of conditions that govern the initiation, rapid propagation, arrest, and ductile tearing of cracks in reactor pressure vessel (RPV) steels. This paper describes recent advances in a coordinated effort being conducted under the HSST Program by ORNL and several subcontracting groups to develop the crack-arrest data base and the analytical tools required to construct inelastic dynamic fracture models for RPV steels. Large-scale tests are being carried out to generate crack-arrest toughness data at temperatures approaching and above the onset of Charpy upper-shelf behavior. Small- and intermediate-size specimens subjected to static and dynamic loading are being developed and tested to provide additional fracture data for RPV steels. Viscoplastic effects are being included in dynamic fracture models and computer programs and their utility validated through analyses of data from carefully controlled experiments. Recent studies are described that examine convergence problems associated with energy-based fracture parameters in viscoplastic-dynamic fracture applications. Alternative techniques that have potential for achieving convergent solutions for fracture parameters in the context of viscoplastic-dynamic models are discussed. 46 refs., 15 figs., 3 tabs.

  3. Seismic waves in rocks with fluids and fractures

    SciTech Connect (OSTI)

    Berryman, J.G.

    2007-05-14

    Seismic wave propagation through the earth is often stronglyaffected by the presence of fractures. When these fractures are filledwith fluids (oil, gas, water, CO2, etc.), the type and state of the fluid(liquid or gas) can make a large difference in the response of theseismic waves. This paper summarizes recent work on methods ofdeconstructing the effects of fractures, and any fluids within thesefractures, on seismic wave propagation as observed in reflection seismicdata. One method explored here is Thomsen's weak anisotropy approximationfor wave moveout (since fractures often induce elastic anisotropy due tononuniform crack-orientation statistics). Another method makes use ofsome very convenient fracture parameters introduced previously thatpermit a relatively simple deconstruction of the elastic and wavepropagation behavior in terms of a small number of fracture parameters(whenever this is appropriate, as is certainly the case for small crackdensities). Then, the quantitative effects of fluids on thesecrack-influence parameters are shown to be directly related to Skempton scoefficient B of undrained poroelasticity (where B typically ranges from0 to 1). In particular, the rigorous result obtained for the low crackdensity limit is that the crack-influence parameters are multiplied by afactor (1 ? B) for undrained systems. It is also shown how fractureanisotropy affects Rayleigh wave speed, and how measured Rayleigh wavespeeds can be used to infer shear wave speed of the fractured medium.Higher crack density results are also presented by incorporating recentsimulation data on such cracked systems.

  4. Analysis of compressive fracture in rock using statistical techniques

    SciTech Connect (OSTI)

    Blair, S.C.

    1994-12-01

    Fracture of rock in compression is analyzed using a field-theory model, and the processes of crack coalescence and fracture formation and the effect of grain-scale heterogeneities on macroscopic behavior of rock are studied. The model is based on observations of fracture in laboratory compression tests, and incorporates assumptions developed using fracture mechanics analysis of rock fracture. The model represents grains as discrete sites, and uses superposition of continuum and crack-interaction stresses to create cracks at these sites. The sites are also used to introduce local heterogeneity. Clusters of cracked sites can be analyzed using percolation theory. Stress-strain curves for simulated uniaxial tests were analyzed by studying the location of cracked sites, and partitioning of strain energy for selected intervals. Results show that the model implicitly predicts both development of shear-type fracture surfaces and a strength-vs-size relation that are similar to those observed for real rocks. Results of a parameter-sensitivity analysis indicate that heterogeneity in the local stresses, attributed to the shape and loading of individual grains, has a first-order effect on strength, and that increasing local stress heterogeneity lowers compressive strength following an inverse power law. Peak strength decreased with increasing lattice size and decreasing mean site strength, and was independent of site-strength distribution. A model for rock fracture based on a nearest-neighbor algorithm for stress redistribution is also presented and used to simulate laboratory compression tests, with promising results.

  5. Laboratory-scale fracture conductivity created by acid etching 

    E-Print Network [OSTI]

    Pournik, Maysam

    2009-05-15

    flow rate (L3/T) uf fracture flow velocity or flux (L/T) ul leak off flow velocity or flux (L/T) wf fracture width (L) wi ideal fracture width (L) wh hydraulic width (L) X volumetric dissolving power of acid (L3 rock /L3 acid) V volume (L3... for power of width m constant E Young?s modulus M Effective modulus of asperity ix ?E activation energy ? inertial flow coefficient ?c closure stress (M/LT2) ?0 initial closure stress (M/LT2) ?y rock yield stress (M/LT2) ?w...

  6. Apparent Fracture in Polymeric Fluids under Step Shear

    E-Print Network [OSTI]

    Okpeafoh S. Agimelen; Peter D. Olmsted

    2013-05-16

    Recent step strain experiments in well-entangled polymeric liquids demonstrated a bulk fracture-like phenomenon. We have studied this instability using a modern version of the Doi-Edwards theory for entangled polymers, and we find close quantitative agreement with the experiments. The phenomenon occurs because the viscoelastic liquid is sheared into a rubbery state that possesses an elastic constitutive instability (Marrucci and Grizzuti, 1983). The fracture is a transient manifestation of this instability, which relies on the amplification of spatially inhomogeneous fluctuations. This mechanism differs from fracture in glassy materials and dense suspensions.

  7. Application of elastic-plastic fracture mechanics to marine structures 

    E-Print Network [OSTI]

    Pathi, Amarkumar

    1991-01-01

    zone size becomes (1. 6) Fracture toughness for materials varies with the specimen thickness, over a particular range of thickness. A typical form of the relationship between fracture toughness Kc and specimen thickness B is shown in Figure L2...-type thermocouple. II. 4 Fracture Toughness Tests The CTOD tests for both the materials were performed in accor- dance with the ASTM CTOD testing standard [23]. A total of 40 single edge notched bend specimens were machined from the EH36 plate and 20 SENB...

  8. Performance of petroleum reservoirs containing random vertical fractures 

    E-Print Network [OSTI]

    Huskey, William Lyman

    1963-01-01

    'so 1 I I o ios 'I \\ I I I I oo I I \\ I I I DISTRIRIJTION OF POTENTIAL IN A VERTICALLY FRACTURED RESE'RVOIR FRACTURE LENGTH 7% OF MODEL RADIUS. FRACTURE DENSI ( Y I. 6 FIGURE 4 14 '" ELK cP o i o o ~o o o~o x ( 'I oh'' I I I... of absence for the purpose of pursuing additional education. REFERENCES Russell, William L. : Structural Geolo for Petroleum Geolo ists, McGraw-Hill Book Company, Inc. , New York, N. Y. , 1955, p. 163. 2, Elkins, Lincoln F. and Skov, Arlie M. : "Deter...

  9. Oil and Gas CDT Prediction of flow through fractures and maximising recovery

    E-Print Network [OSTI]

    Henderson, Gideon

    fracking. Fractured carbonate formation in Morocco The project aims to tackle the problem of quantifying

  10. An Innovative Closed Fracture Acidizing Technique for Deep Carbonate Reservoirs Using GLDA 

    E-Print Network [OSTI]

    He, Jia

    2015-08-07

    . .............................................................................. 77 Fig. 32—CT images of Core #38 (without mini-fractures). ............................................ 78 Fig. 33—CT images of Core #32 (without mini-fractures). ............................................ 78 Fig. 34—CT images of Core #33... (without mini-fractures). ............................................ 79 Fig. 35—CT images of Core #37 (without mini-fractures). ............................................ 79 Fig. 36—Acid etching profiles of Core #33...

  11. Experimental study of the transition from brittle shear fractures to joints 

    E-Print Network [OSTI]

    Ramsey, Jonathan Michael

    2003-01-01

    Current geologic thinking is that there are two, and only two, distinct types of brittle fractures, joints and shear fractures (faults). For over half a century, it has been debated that a third type of fracture, referred to as hybrid fractures...

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

    Broader source: Energy.gov [DOE]

    Project objective: Develop Improved Methods For Maintaining Permeable Fracture Volumes In EGS Reservoirs.

  13. Transport of conservative solutes in simulated fracture networks: 1. Synthetic data generation

    E-Print Network [OSTI]

    Meerschaert, Mark M.

    including high- level radioactive waste. Fractures can serve as primary pathways for fluid flow and wasteTransport of conservative solutes in simulated fracture networks: 1. Synthetic data generation. If this statistical model applies to transport in fractured media, then an ensemble plume in a fractured rock domain

  14. Interaction between Injection Points during Hydraulic Fracturing Kjetil M. D. Hals1,

    E-Print Network [OSTI]

    Santos, Juan

    fluid to create fracture networks in rock layers with low permeabilities. A fracking fluid is injected

  15. Enrichment strategies and convergence properties of the XFEM for hydraulic fracture problems

    E-Print Network [OSTI]

    Peirce, Anthony

    Enrichment strategies and convergence properties of the XFEM for hydraulic fracture problems Finite Ele- ment Method (XFEM) for modeling hydraulic fractures (HF), two classes of boundary value energy, is not suitable for modeling hydraulic fractures in which the uid and the fracture fronts

  16. Spall-Fracture Physics and Spallation-Resistance-Based Material Selection

    E-Print Network [OSTI]

    Grujicic, Mica

    Spall-Fracture Physics and Spallation-Resistance-Based Material Selection M. Grujicic, B. Pandurangan, B.A. Cheeseman, and C.-F. Yen (Submitted July 29, 2011) Spallation is a fracture mode commonly cause material damage and ultimate fracture (spallation). In this study, the phenomenon of spall-fracture

  17. Fracture response of externally flawed aluminum cylindrical shells under internal gaseous detonation loading

    E-Print Network [OSTI]

    Barr, Al

    Fracture response of externally flawed aluminum cylindrical shells under internal gaseous. Experiments were performed to observe the fracture behavior of thin- wall and initially-flawed aluminum tubes to different fracture events are analyzed. Keywords: tube fracture, detonation, crack branching, crack curving

  18. ynamic fracture occupies a peculiar niche in the study of materials. One of

    E-Print Network [OSTI]

    Texas at Austin. University of

    D ynamic fracture occupies a peculiar niche in the study of materials. One of the first things, scientists and engineers studying fracture mechanics focus on determining the critical con- ditions, created, and picoseconds to microseconds, so as to compare theory and experiment for brittle fracture. Strip fracture One

  19. Two mechanisms of ductile fracture: void by void growth versus multiple void interaction

    E-Print Network [OSTI]

    Hutchinson, John W.

    Elsevier Science Ltd. All rights reserved. Keywords: Fracture toughness; Ductile fracture; Void nucleationTwo mechanisms of ductile fracture: void by void growth versus multiple void interaction Viggo of ductile fracture. One is the interaction a single void with the crack tip characterizing initiation

  20. A Visual Model For Blast Waves and Fracture Michael Neff Eugene Fiume

    E-Print Network [OSTI]

    Toronto, University of

    A Visual Model For Blast Waves and Fracture Michael Neff Eugene Fiume Department of Computer for fracturing materials loaded by a blast. Our approach is based on the notion of rapid fracture: that microfractures in a material together with loading forces seed a fracturing process that quickly spreads across

  1. Structural parameters The analytical model proposed here can explain high fracture

    E-Print Network [OSTI]

    Barthelat, Francois

    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

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

    SciTech Connect (OSTI)

    Not Available

    1991-10-01

    The first of a 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 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 were conducted with a dual porosity simulator capable of simulating the performance of vertical and horizontal wells. Each simulator was initialized using properties typical of the Austin Chalk reservoir in Pearsall Field, Texas. Simulations of both vertical and horizontal well performance were made assuming that fracture permeability was insensitive to pressure change. Sensitivity runs indicate that the simulator is predicting the effects of critical reservoir parameters in a logical and consistent manner. The results to-date confirm that horizontal wells can increase both oil recovery rate and total oil recovery from naturally fractured reservoirs. The year one simulation results will provide the baseline for the ongoing study which will evaluate the performance degradation caused by the sensitivity of fracture permeability to pressure change, and investigate fluid injection pressure maintenance as a means to improve oil recovery performance. The study is likely to conclude that fracture closure decreases oil recovery and that pressure support achieved through fluid injection could be beneficial in improving recovery.

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

    SciTech Connect (OSTI)

    Not Available

    1992-11-01

    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.

  4. Exploration Technologies - Technology Needs Assessment

    SciTech Connect (OSTI)

    Greene, Amanda I.; Thorsteinsson, Hildigunnur; Reinhardt, Tim; Solomon, Samantha; James, Mallory

    2011-06-01

    This assessment is a critical component of ongoing technology roadmapping efforts, and will be used to guide the Geothermal Technology Program's research and development.

  5. Predicting hip fracture type with cortical bone mapping (CBM) in the Osteoporotic Fractures in Men (MrOS) study

    E-Print Network [OSTI]

    Treece, Graham M.; Gee, Andrew H.; Tonkin, Carol; Ewing, Susan K.; Cawthon, Peggy M.; Black, Dennis M.; Poole, Kenneth E. S.; Osteoporotic Fractures in Men Study

    2015-03-18

    for hazard ratios were conducted in SAS version 9.1 (SAS Institute, Cary, NC, USA). In addition, we examined the ability of models involving different groups of variables to predict ten-year fracture incidence, by performing either binomial (any fracture... CD, Delmas P, et al. Predictive value of BMD for hip and other fractures. J Bone Miner Res. 2005;20(7):1185–1194. 3. Kanis JA, Burlet N, Cooper C, Delmas PD, Reginster JY, Borgstrom F, et al. European guidance for the diagnosis and management...

  6. X-231A demonstration of in-situ remediation of DNAPL compounds in low permeability media by soil fracturing with thermally enhanced mass recovery or reactive barrier destruction

    SciTech Connect (OSTI)

    Siegrist, R.L.; Lowe, K.S.; Murdoch, L.D.; Slack, W.W.; Houk, T.C.

    1998-03-01

    The overall goal of the program of activities is to demonstrate robust and cost-effective technologies for in situ remediation of DNAPL compounds in low permeability media (LPM), including adaptations and enhancements of conventional technologies to achieve improved performance for DNAPLs in LPM. The technologies sought should be potential for application at simple, small sites (e.g., gasoline underground storage tanks) as well as at complex, larger sites (e.g., DOE land treatment units). The technologies involved in the X-231A demonstration at Portsmouth Gaseous Diffusion Plant (PORTS) utilized subsurface manipulation of the LPM through soil fracturing with thermally enhanced mass recovery or horizontal barrier in place destruction. To enable field evaluation of these approaches, a set of four test cells was established at the X-231A land treatment unit at the DOE PORTS plant in August 1996 and a series of demonstration field activities occurred through December 1997. The principal objectives of the PORTS X-231A demonstration were to: determine and compare the operational features of hydraulic fractures as an enabling technology for steam and hot air enhanced soil vapor extraction and mass recovery, in situ interception and reductive destruction by zero valent iron, and in situ interception and oxidative destruction by potassium permanganate; determine the interaction of the delivered agents with the LPM matrix adjacent to the fracture and within the fractured zone and assess the beneficial modifications to the transport and/or reaction properties of the LPM deposit; and determine the remediation efficiency achieved by each of the technology strategies.

  7. Orientation Estimation for Multiple Large Fractures by Scattering Energy

    E-Print Network [OSTI]

    Zhang, Yang

    2006-01-01

    We have done the numerical modeling of seismic response to multiple sets of vertical large fractures by using finite-difference method (FD), which can easily handle media with monoclinic anisotropy. We consider three types ...

  8. Finding Large Aperture Fractures in Geothermal Resource Areas...

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

    A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis Finding Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component...

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

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

    Scale Model Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs; II: Full-Waveform Inversion of 3D-9C VSP data from Bradys EGS Site...

  10. Simulation of naturally fractured reservoirs using empirical transfer function 

    E-Print Network [OSTI]

    Tellapaneni, Prasanna Kumar

    2004-09-30

    This research utilizes the imbibition experiments and X-ray tomography results for modeling fluid flow in naturally fractured reservoirs. Conventional dual porosity simulation requires large number of runs to quantify transfer function parameters...

  11. Effect of loading history in necking and fracture

    E-Print Network [OSTI]

    Bai, Yuanli

    2008-01-01

    The effect of Lode angle parameter, or the third deviatoric stress invariant, on plasticity and fracture is studied using flat-grooved transverse plane strain specimens. A generalized asymmetric plasticity model for isotropic ...

  12. Evaluation of the stiffness tensor of a fractured medium with ...

    E-Print Network [OSTI]

    igpuba]CONICET, Instituto del Gas y del Petróleo, Facultad de Ingenie? a, Universidad de ... The specific viscosity accounts for the presence of a viscous liquid under ...... geologic perspectives on geophysical prospecting for natural fractures.

  13. Water Withdrawals for Hydraulic Fracturing (Updated May 7, 2014)

    E-Print Network [OSTI]

    Walter, M.Todd

    Water Withdrawals for Hydraulic Fracturing (Updated May 7, 2014) Hydraulic require millions of gallons of water. In Pennsylvania, for example, hydraulic gallons of water over a 2 to 5 day period (SRBC). Natural gas industry

  14. Predicting proppant flowback from fracture-stimulated wells 

    E-Print Network [OSTI]

    Canon Moreno, Javier Mauricio

    2003-01-01

    In this thesis, the usefulness and benefits of predicting proppant flowback in the design stage of hydraulic fracturing treatments are evidenced. A new prediction model, as well as a methodology, is proposed in this work. ...

  15. Multiporosity Flow in Fractured Low-Permeability Rocks

    E-Print Network [OSTI]

    Kuhlman, Kristopher L; Heath, Jason E

    2015-01-01

    A multiporosity extension of classical double and triple porosity fractured rock flow models for slightly compressible fluids is presented. The multiporosity model is an adaptation of the multirate solute transport model of Haggerty and Gorelick (1995) to viscous flow in fractured rock reservoirs. It is a generalization of both pseudo-steady-state and transient interporosity flow double porosity models. The model includes a fracture continuum and an overlapping distribution of multiple rock matrix continua, whose fracture-matrix exchange coefficients are specified through a discrete probability mass function. Semi-analytical cylindrically symmetric solutions to the multiporosity mathematical model are developed using the Laplace transform to illustrate its behavior. The multiporosity model presented here is conceptually simple, yet flexible enough to simulate common conceptualizations of double and triple porosity flow. This combination of generality and simplicity makes the multiporosity model a good choice ...

  16. The Performance of Fractured Horizontal Well in Tight Gas Reservoir 

    E-Print Network [OSTI]

    Lin, Jiajing

    2012-02-14

    Horizontal wells have been used to increase reservoir recovery, especially in unconventional reservoirs, and hydraulic fracturing has been applied to further extend the contact with the reservoir to increase the efficiency of development...

  17. Optimization of fractured well performance of horizontal gas wells 

    E-Print Network [OSTI]

    Magalhaes, Fellipe Vieira

    2009-06-02

    In low-permeability gas reservoirs, horizontal wells have been used to increase the reservoir contact area, and hydraulic fracturing has been further extending the contact between wellbores and reservoirs. This thesis presents an approach...

  18. Pressure Testing of a High Temperature Naturally Fractured Reservoir...

    Office of Scientific and Technical Information (OSTI)

    m). The formation is a naturally fractured granite at temperatures of about 250 C. The matrix porosity is < 1%and permeability is on the order of 1 nD (10 msup 2). Hence most of...

  19. Transient and Pseudosteady-State Productivity of Hydraulically Fractured Well 

    E-Print Network [OSTI]

    Lumban Gaol, Ardhi

    2012-10-19

    Numerical simulation method is used in this work to solve the problem of transient and pseudosteady-state flow of fluid in a rectangular reservoir with impermeable boundaries. Development and validation of the numerical solution for various well-fracture...

  20. 1112323-danimer-abstract-hydraulic-fractures | netl.doe.gov

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

    have significant impact on the industry as the NFT process could be applicable on 40% of hydraulic fracturing treatments in the U.S. The process is applicable on wells that...

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

    Broader source: Energy.gov [DOE]

    Project objective: to develop a 3-D numerical model for simulating mode I; II; and III (tensile; shear; and tearing propagation of multiple fractures using the virtual multi-dimensional internal bond (VMIB); to predict geothermal reservoir stimulation.

  2. Model for Fracturing Fluid Flowback and Characterization of Flowback Mechanisms 

    E-Print Network [OSTI]

    Song, Bo

    2014-08-28

    that may or may not be filled with injected fluid or proppant or even hydraulically connected. The investigation of factors impacting water retention will consider formation properties and fracture configurations of the cataloged locations for injected...

  3. Fracture Toughness and Maximum Stress in a Disordered Lattice System

    E-Print Network [OSTI]

    Chiyori Urabe; Shinji Takesue

    2008-12-29

    Fracture in a disordered lattice system is studied. In our system, particles are initially arranged on the triangular lattice and each nearest-neighbor pair is connected with a randomly chosen soft or hard Hookean spring. Every spring has the common threshold of stress at which it is cut. We make an initial crack and expand the system perpendicularly to the crack. We find that the maximum stress in the stress-strain curve is larger than those in the systems with soft or hard springs only (uniform systems). Energy required to advance fracture is also larger in some disordered systems, which indicates that the fracture toughness improves. The increase of the energy is caused by the following two factors. One is that the soft spring is able to hold larger energy than the hard one. The other is that the number of cut springs increases as the fracture surface becomes tortuous in disordered systems.

  4. Irradiation Effects on Human Cortical Bone Fracture Behavior

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

    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...

  5. Numerical modeling of hydraulic fracture initiation and development

    E-Print Network [OSTI]

    2007-05-25

    Studying initiation and propagation of hydraulic fractures is carried out based on the hypersingular ... and for geothermal energy ...... means of enhancing oil and gas recovery, and it serves its purpose if propagates for tens or hundreds meters.

  6. Horizontal Code Transfer via Program Fracture and Recombination

    E-Print Network [OSTI]

    Sidiroglou-Douskos, Stelios

    2015-04-14

    We present a new horizontal code transfer technique, program fracture and recombination, for automatically replacing, deleting, and/or combining code from multiple applications. Benefits include automatic generation of new ...

  7. Seismic signatures of two orthogonal sets of vertical microcorrugated fractures

    E-Print Network [OSTI]

    Tsvankin, Ilya

    surface seismic and VSP (vertical seismic profiling) data. Using the linear- slip theory describedSeismic signatures of two orthogonal sets of vertical microcorrugated fractures Rodrigo Fel propagation through an effective anisotropic medium that contains two microcorrugated, vertical, orthogonal

  8. Brittle Fracture Modeling with a Surface Tension Excess Property 

    E-Print Network [OSTI]

    Ferguson, Lauren

    2012-10-30

    The classical theory of linear elastic fracture mechanics for a quasi-static crack in an infinite linear elastic body has two significant mathematical inconsistencies: it predicts unbounded crack-tip stresses and an ...

  9. Seismic waves in rocks with fluids and fractures

    E-Print Network [OSTI]

    Berryman, J.G.

    2008-01-01

    23. u Grechka, V. , 2005. Penny-shaped fractures revisited,at cracks when they are penny-shaped as assumed here). Thesethe radius of the (assumed) penny-shaped crack, and a/b is

  10. “Electrochemical Shock” of Intercalation Electrodes: A Fracture Mechanics Analysis

    E-Print Network [OSTI]

    Chiang, Yet-Ming

    Fracture of electrode particles due to diffusion-induced stress has been implicated as a possible mechanism for capacity fade and impedance growth in lithium-ion batteries. In brittle materials, including many lithium ...

  11. Thermally Activated Technologies Technology Roadmap, May 2003...

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

    Thermally Activated Technologies Technology Roadmap, May 2003 Thermally Activated Technologies Technology Roadmap, May 2003 The purpose of this Technology Roadmap is to outline a...

  12. Geochemical and Geomechanical Effects on Wellbore Cement Fractures

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

    Um, Wooyong; Jung, Hun Bok; Kabilan, Senthil; Fernandez, Carlos A.; Brown, Christopher F.

    2014-12-31

    Experimental studies were conducted using batch reactors, X-ray microtomograpy (XMT), and computational fluid dynamics (CFD) simulation to determine changes in cement fracture surfaces, fluid flow pathways, and permeability with geochemical and geomechanical processes. Composite Portland cement-basalt caprock core with artificial fractures was prepared and reacted with CO2-saturated groundwater at 50°C and 10 MPa for 3 to 3.5 months under static conditions to understand the geochemical and geomechanical effects on the integrity of wellbores containing defects. Cement-basalt interface samples were subjected to mechanical stress at 2.7 MPa before the CO2 reaction. XMT provided three-dimensional (3-D) visualization of the opening and interconnectionmore »of cement fractures due to mechanical stress. After the CO2 reaction, XMT images revealed that calcium carbonate precipitation occurred extensively within the fractures in the cement matrix, but only partially along fractures located at the cement-basalt interface. The permeability calculated based on CFD simulation was in agreement with the experimentally measured permeability. The experimental results imply that the wellbore cement with fractures is likely to be healed during exposure to CO2-saturated groundwater under static conditions, whereas fractures along the cement-caprock interface are still likely to remain vulnerable to the leakage of CO2. CFD simulation for the flow of different fluids (CO2-saturated brine and supercritical CO2) using a pressure difference of 20 kPa and 200 kPa along ~2 cm-long cement fractures showed that a pressure gradient increase resulted in an increase of CO2 fluids flux by a factor of only ~3-9 because the friction of CO2 fluids on cement fracture surfaces increased with higher flow rate as well. At the same pressure gradient, the simulated flow rate was higher for supercritical CO2 than CO2-saturated brine by a factor of only ~2-3, because the viscosity of supercritical CO2 is much lower than that of CO2-saturated brine. The study suggests that in deep geological reservoirs the geochemical and geomechanical processes have coupled effects on the wellbore cement fracture evolution and fluid flow along the fracture surfaces.« less

  13. Fracture and Healing of Rock Salt Related to Salt Caverns

    SciTech Connect (OSTI)

    Chan, K.S.; Fossum, A.F.; Munson, D.E.

    1999-03-01

    In recent years, serious investigations of potential extension of the useful life of older caverns or of the use of abandoned caverns for waste disposal have been of interest to the technical community. All of the potential applications depend upon understanding the reamer in which older caverns and sealing systems can fail. Such an understanding will require a more detailed knowledge of the fracture of salt than has been necessary to date. Fortunately, the knowledge of the fracture and healing of salt has made significant advances in the last decade, and is in a position to yield meaningful insights to older cavern behavior. In particular, micromechanical mechanisms of fracture and the concept of a fracture mechanism map have been essential guides, as has the utilization of continuum damage mechanics. The Multimechanism Deformation Coupled Fracture (MDCF) model, which is summarized extensively in this work was developed specifically to treat both the creep and fracture of salt, and was later extended to incorporate the fracture healing process known to occur in rock salt. Fracture in salt is based on the formation and evolution of microfractures, which may take the form of wing tip cracks, either in the body or the boundary of the grain. This type of crack deforms under shear to produce a strain, and furthermore, the opening of the wing cracks produce volume strain or dilatancy. In the presence of a confining pressure, microcrack formation may be suppressed, as is often the case for triaxial compression tests or natural underground stress situations. However, if the confining pressure is insufficient to suppress fracture, then the fractures will evolve with time to give the characteristic tertiary creep response. Two first order kinetics processes, closure of cracks and healing of cracks, control the healing process. Significantly, volume strain produced by microfractures may lead to changes in the permeability of the salt, which can become a major concern in cavern sealing and operation. The MDCF model is used in three simulations of field experiments in which indirect measures were obtained of the generation of damage. The results of the simulations help to verify the model and suggest that the model captures the correct fracture behavior of rock salt. The model is used in this work to estimate the generation and location of damage around a cylindrical storage cavern. The results are interesting because stress conditions around the cylindrical cavern do not lead to large amounts of damage. Moreover, the damage is such that general failure can not readily occur, nor does the extent of the damage suggest possible increased permeation when the surrounding salt is impermeable.

  14. Recovery of oil from fractured reservoirs by gas displacement 

    E-Print Network [OSTI]

    Unneberg, Arild

    1974-01-01

    RECOVERY OF OIL FROM FRACTURED RESERVOIRS BY GAS DISPLACEMENT A Thesis by ARILD UNNE BE RG Submitted to the Graduate College of Texas AlkM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1974... Major Subject: Petroleum Engineering RECOVERY OF OIL FROM FRACTURED RESERVOIRS BY GAS DISPLACEMENT A Thesis by ARILD UNNEBERG Approved as, to style and content by: . ( y (Chairman of Cornrnittee) (Head of Depar nt) / (Membe r) (Member) M b...

  15. An analysis of a biodegradable intramedullary fracture fixation system 

    E-Print Network [OSTI]

    Smith, William Keith

    1991-01-01

    AN ANALYSIS OF A BIODEGRADABLE INTRAMEDULLARY FRACTURE FIXATION SYSTEM A Thesis by WILLIAM KEITH SMITH Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER... remodeling of existing Haversion systems; cutting cones resorb and deposit bone simultaneously as they cross the fracture gap, Secondary bone union occurs in three stages: inflammation, repair, and remodeling. Secondary bone union is characterized...

  16. A void growth model relating fracture toughness and constraint 

    E-Print Network [OSTI]

    Miller, Timothy Clark

    1992-01-01

    , Hartwig (member) Dr, , K. Kinra (member) Dr. W, L. Bradley (Head of Department) August 1992 ABSTRACT A Void Model Relating Fracture Toughness and Constraint. (August 1992) Timothy Clark Miller, B. S. , Texas ARM University Chair of Advisory... bonded). 3 f" ) (a) particles (b) nucleation (c) void grovvtb (d) coalescence Figure 1. Void phenomena and ductile fracture of a metal (Ada@ed horn [11] ) (a) initial state (b) void growth at tip ~ ' ':. ~ . :; -. . e-"""", ? ' " (c...

  17. Neutron Production from the Fracture of Piezoelectric Rocks

    E-Print Network [OSTI]

    A. Widom; J. Swain; Y. N. Srivastava

    2012-02-08

    A theoretical explanation is provided for the experimental evidence that fracturing piezoelectric rocks produces neutrons. The elastic energy micro-crack production ultimately yields the macroscopic fracture. The mechanical energy is converted by the piezoelectric effect into electric field energy. The electric field energy decays via radio frequency (microwave) electric field oscillations. The radio frequency electric fields accelerate the condensed matter electrons which then collide with protons producing neutrons and neutrinos.

  18. Slow Waves in Fractures Filled with Viscous Fluid

    SciTech Connect (OSTI)

    Korneev, Valeri

    2008-01-08

    Stoneley guided waves in a fluid-filled fracture generally have larger amplitudes than other waves, and therefore, their properties need to be incorporated in more realistic models. In this study, a fracture is modeled as an infinite layer of viscous fluid bounded by two elastic half-spaces with identical parameters. For small fracture thickness, I obtain a simple dispersion equation for wave-propagation velocity. This velocity is much smaller than the velocity of a fluid wave in a Biot-type solution, in which fracture walls are assumed to be rigid. At seismic prospecting frequencies and realistic fracture thicknesses, the Stoneley guided wave has wavelengths on the order of several meters and an attenuation Q factor exceeding 10, which indicates the possibility of resonance excitation in fluid-bearing rocks. The velocity and attenuation of Stoneley guided waves are distinctly different at low frequencies for water and oil. The predominant role of fractures in fluid flow at field scales is supported by permeability data showing an increase of several orders of magnitude when compared to values obtained at laboratory scales. These data suggest that Stoneley guided waves should be taken into account in theories describing seismic wave propagation in fluid-saturated rocks.

  19. The use of broadband microseisms for hydraulic fracture mapping

    SciTech Connect (OSTI)

    Sleefe, G.E.; Warpinski, N.R.; Engler, B.P.

    1993-08-01

    When a hydrocarbon reservoir is subjected to a hydraulic fracture treatment, the cracking and slipping of the formation results in the emission of seismic energy. The objective of this study was to determine the advantages of using broadband (100 Hz to 1500 M) microseismic emissions to map a hydraulic fracture treatment. A hydraulic fracture experiment was performed in the Piceance Basin of Western Colorado to induce and record broadband microseismic events. The formation was subjected to four processes; break-down/ballout, step-rate test, KCL mini-fracture, and linear-gel mini-fracture. Broadband microseisms were successfully recorded by a novel three-component wall-locked seismic accelerometer package, placed in an observation well 211 ft (64 m) offset from the treatment well. During the two hours of formation treatment, more than 1200 significant microseismic events were observed. The occurrences of the events strongly correlated with the injection bore-bole pressures during the treatments. Using both hodogram analysis and time of arrival information, estimates of the origination point of the seismic events were computed. A map of the event locations yielded a fracture orientation estimate consistent with the known orientation of the field in the formation. This paper describes the technique for acquiring and analyzing broadband microseismic events and illustrate how the new broadband approach can enhance signal detectability and event location resolution.

  20. The Effects of Initial Condition of Fracture Surfaces, Acid Spending, and Type on Conductivity of Acid Fracture 

    E-Print Network [OSTI]

    Almomen, Ali Mansour

    2013-07-24

    . Another area of interest is the variation of conductivity along the fracture due to acid spending. We also investigated the contact time, acid system type, and treatment temperature effects on conductivity using San Andres dolomite cores. The results...

  1. Assessment of fracture properties and rate effects on fracture of materials by micro scratching: application to gas shale

    E-Print Network [OSTI]

    Akono, Ange-Therese

    2013-01-01

    Since 1921, several experimental methods have been implemented to measure the Griffith fracture energy. The challenge lies in providing a measure that is intrinsic and invariant with respect to external factors such as ...

  2. Geothermal Injection Technology Program: Annual progress report, Fiscal Year 1986

    SciTech Connect (OSTI)

    Not Available

    1987-07-01

    This report summarizes the Geothermal Injection Technology Program major activities in fiscal year 1986. The Idaho Engineering Laboratory (INEL) and the University of Utah Research Institute (UURI) have been conducting injection research and testing for this program, which was initiated in 1983. Activities at the INEL, representative element nodeling of fracture systems based on stochastic analysis, dual permeability modeling of flow in a fractured geothermal reservoir, and dual permeability model - laboratory and FRACSL-validation studies, are presented first, followed by the University of Utah Research Institute tracer development - experimental studies, which includes a brief description of activities planned for FY-1987.

  3. To mechanics of deformation, flow, and fracture

    E-Print Network [OSTI]

    S. L. Arsenjev

    2008-09-23

    It is stated in the main in essence new approach to mechanics of the stressed state of the solid body from statistically isotropic material and the homogeneous liquid dynamics. The approach essence is in the detected property of the core-shell spontaneous structurization of internal energy of the solid and liquid bodies in its natural state and under action of external forces. The method elements of construction of physically adequate model of the stressed state of the solid and liquid bodies, reproduced exactly its behavior on the stages of elastic and plastic deformation, flow and fracture, are stated. It is adduced a number of the examples of the stressed state construction of the simple form bodies under action of its tension, compression, torsion and at its contact interaction. For the first time it is adduced structure of the principal - normal - stresses in cylindrical bar under action of the torsion moment. The detected property and the developed method is one of necessary bases for construction of physically adequate mathematical model of the stressed state of the body and fluid in contrast to traditional approach.

  4. Determination of fracture and reservoir properties using an automatic history matching technique for wells with finite-conductivity vertical fractures 

    E-Print Network [OSTI]

    Santhanam, Kalakad Sundhareswaraiyer

    1985-01-01

    ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December 1985 Major Subject: Petroleum Engineering DETERMINATION OF FRACTURE AND RESERVOIR PROPERTIES USING AN AUTOMATIC HISTORY MATCHING TECHNIQUE... FOR WELLS WITH FINITE-CONDUCTIVITY VERTICAL FRACTURES A Thesis by KALAKAD SUNDHARESWARAIYER SANTHANAM Approved as to style and content by William John Lee (Chairman of Commitee) Stephen A. Holditch (Member) Robert R. Berg (Member) Willi D. Von...

  5. Simulation studies to evaluate the effect of fracture closure on the performance of fractured reservoirs; Final report

    SciTech Connect (OSTI)

    Howrie, I.; Dauben, D.

    1994-03-01

    A 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 were to: (1) evaluate the reservoir conditions for which fracture closure is significant, and (2) evaluate innovative fluid injection techniques capable of maintaining pressure within the reservoir. The evaluations of reservoir performance were made by a modern dual porosity simulator, TETRAD. This simulator treats both porosity and permeability as functions of pore pressure. The Austin Chalk in the Pearsall Field in of South Texas was selected as the prototype fractured reservoir for this work. During the first year, simulations of vertical and horizontal well performance were made assuming that fracture permeability was insensitive to pressure change. Sensitivity runs indicated that the simulator was predicting the effects of critical reservoir parameters in a logical and consistent manner. The results confirmed that horizontal wells could increase both rate of oil recovery and total oil recovery from naturally fractured reservoirs. In the second year, the performance of the same vertical and horizontal wells was reevaluated with fracture permeability treated as a function of reservoir pressure. To investigate sensitivity to in situ stress, differing loading conditions were assumed. Simulated natural depletions confirm that pressure sensitive fractures degrade well performance. The severity of degradation worsens when the initial reservoir pressure approaches the average stress condition of the reservoir, such as occurs in over pressured reservoirs. Simulations with water injection indicate that degradation of permeability can be counteracted when reservoir pressure is maintained and oil recovery can be increased when reservoir properties are favorable.

  6. The development of in situ fracture toughness evaluation techniques in hydrogen environment

    SciTech Connect (OSTI)

    Wang, Jy-An John; Ren, Fei; Tan, Ting; Liu, Ken C

    2014-01-01

    Fracture behavior and fracture toughness are of great interest regarding reliability of hydrogen pipelines and storage tanks, however, many conventional fracture testing techniques are difficult to be realized under the presence of hydrogen, in addition to the inherited specimen size effect. Thus it is desired to develop novel in situ fracture toughness evaluation techniques to study the fracture behavior of structural materials in hydrogen environments. In this study, a torsional fixture was developed to utilize an emerging fracture testing technique, Spiral Notch Torsion Test (SNTT). The in situ testing results indicated that the exposure to H2 significantly reduces the fracture toughness of 4340 high strength steels by up to 50 percent. Furthermore, SNTT tests conducted in air demonstrated a significant fracture toughness reduction in samples subject to simulated welding heat treatment using Gleeble, which illustrated the effect of welding on the fracture toughness of this material.

  7. Advanced aircraft engine microlaminated intermetallic composite turbine technology

    SciTech Connect (OSTI)

    Rowe, R.G.; Skelly, D.W.; Jackson, M.R.; Larsen, M. [GE Corporate Research and Development, Schenectady, NY (United States); Lachapelle, D. [GE Aircraft Engines, Cincinnati, OH (United States)

    1996-12-31

    Higher gas path temperatures for greater aircraft engine thrust and efficiency will require both higher temperature gas turbine airfoil materials and optimization of internal cooling technology. Microlaminated composites consisting of very high temperature intermetallic compounds and ductile refractory metals offer a means of achieving higher temperature turbine airfoil capability without sacrificing low temperature fracture resistance. Physical vapor deposition, used to synthesize microlaminated composites, also offers a means of fabricating advanced turbine blade internal cooling designs. The low temperature fracture resistance of microlaminated Nb(Cr)-Cr{sub 2}Nb microlaminated composites approached 20 MPa{radical}m in fracture resistance curves, but the fine grain size of vapor deposited intermetallics indicates a need to develop creep resistant microstructures.

  8. IDENTIFYING FRACTURE ORIGIN IN CERAMICS BY COMBINATION OF NONDESTRUCTIVE TESTING AND DISCRETE ELEMENT ANALYSIS

    SciTech Connect (OSTI)

    Senapati, Rajeev; Zhang Jianmei

    2010-02-22

    Advanced ceramic materials have been extensively applied in aerospace, automobile and other industries. However, the reliability of the advanced ceramics is a major concern because of the brittle nature of the materials. In this paper, combination of nondestructive testing and numerical modeling Discrete Element Method is proposed to identify the fracture origin in ceramics. The nondestructive testing--laser scattering technology is first performed on the ceramic components to reveal the machining-induced damage such as cracks and the material-inherent flaws such as voids, then followed by the four point bending test. Discrete Element software package PFC{sup 2D} is used to simulate the four point bending test and try to identify where the fractures start. The numerical representation of the ceramic materials is done by generating a densely packed particle system using the specimen genesis procedure and then applying the suitable microparameters to the particle system. Simulation of four point bending test is performed on materials having no defects, materials having manufacturing-induced defects like cracks, and materials having material-inherent flaws like voids. The initiation and propagation of defects is modeled and the mean contact force on the loading ball is also plotted. The simulation prediction results are well in accordance with the nondestructive testing results.

  9. Integrated seismic study of naturally fractured tight gas reservoirs

    SciTech Connect (OSTI)

    Mavko, G.M.; Nur, A.

    1993-12-31

    Reflection seismic methods are, and will continue to be, the key geophysical tool for imaging these heterogeneities in the subsurface of the earth. However, in spite of great advances in field acquisition techniques and computer processing power, the primary product of conventional seismic work is still only the spatial pattern of reflectivity, which is a measure of velocity variations. Most of the amplitude information goes unused. Although fracture zones may have a reflectivity signature, more often they will not, because of steeply dipping angles, limited offset range in the acquisition, a subtle impedance mismatch, or too thin a fractured zone relative to the wavelength. In fact, there is probably no single seismic attribute that will always tell us what we need to know about fracture zones. Our objective, in the project, is to integrate the principles of rock physics into a quantitative interpretation scheme that exploits the broader spectrum of fracture zone signatures: anomalous compressional and shear wave velocities; Q and velocity dispersion; increased velocity anisotropy amplitude variation with offset (AVO) response. Our goal is to incorporate four key elements: Acquisition and processing of seismic reflection field data. Theoretical studies of the anisotropic signatures of fractured rocks. Laboratory measurements of seismic velocity, velocity anisotropy, and attenuation in reservoir and cap rocks. Integration and interpretation of seismic, well log, and laboratory data, incorporating forward modeling.

  10. Investigation of Possible Wellbore Cement Failures During Hydraulic Fracturing Operations

    SciTech Connect (OSTI)

    Kim, Jihoon; Moridis, George

    2014-11-01

    We model and assess the possibility of shear failure, using the Mohr-Coulomb model ? along the vertical well by employing a rigorous coupled flow-geomechanic analysis. To this end, we vary the values of cohesion between the well casing and the surrounding cement to representing different quality levels of the cementing operation (low cohesion corresponds to low-quality cement and/or incomplete cementing). The simulation results show that there is very little fracturing when the cement is of high quality.. Conversely, incomplete cementing and/or weak cement can causes significant shear failure and the evolution of long fractures/cracks along the vertical well. Specifically, low cohesion between the well and cemented areas can cause significant shear failure along the well, but the same cohesion as the cemented zone does not cause shear failure. When the hydraulic fracturing pressure is high, low cohesion of the cement can causes fast propagation of shear failure and of the resulting fracture/crack, but a high-quality cement with no weak zones exhibits limited shear failure that is concentrated near the bottom of the vertical part of the well. Thus, high-quality cement and complete cementing along the vertical well appears to be the strongest protection against shear failure of the wellbore cement and, consequently, against contamination hazards to drinking water aquifers during hydraulic fracturing operations.

  11. Modeling the Fracture of Ice Sheets on Parallel Computers

    SciTech Connect (OSTI)

    Waisman, Haim; Tuminaro, Ray

    2013-10-10

    The objective of this project was to investigate the complex fracture of ice and understand its role within larger ice sheet simulations and global climate change. This objective was achieved by developing novel physics based models for ice, novel numerical tools to enable the modeling of the physics and by collaboration with the ice community experts. At the present time, ice fracture is not explicitly considered within ice sheet models due in part to large computational costs associated with the accurate modeling of this complex phenomena. However, fracture not only plays an extremely important role in regional behavior but also influences ice dynamics over much larger zones in ways that are currently not well understood. To this end, our research findings through this project offers significant advancement to the field and closes a large gap of knowledge in understanding and modeling the fracture of ice sheets in the polar regions. Thus, we believe that our objective has been achieved and our research accomplishments are significant. This is corroborated through a set of published papers, posters and presentations at technical conferences in the field. In particular significant progress has been made in the mechanics of ice, fracture of ice sheets and ice shelves in polar regions and sophisticated numerical methods that enable the solution of the physics in an efficient way.

  12. Computerized tomographic analysis of fluid flow in fractured tuff

    SciTech Connect (OSTI)

    Felice, C.W.; Sharer, J.C.; Springer, E.P.

    1992-05-01

    The purpose of this summary is to demonstrate the usefulness of X-ray computerized tomography to observe fluid flow down a fracture and rock matrix imbibition in a sample of Bandelier tuff. This was accomplished by using a tuff sample 152.4 mm long and 50.8 mm in diameter. A longitudinal fracture was created by cutting the core with a wire saw. The fractured piece was then coupled to its adjacent section to that the fracture was not expected. Water was injected into a dry sample at five flow rates and CT scanning performed at set intervals during the flow. Cross sectional images and longitudinal reconstructions were built and saturation profiles calculated for the sample at each time interval at each flow rate. The results showed that for the test conditions, the fracture was not a primary pathway of fluid flow down the sample. At a slow fluid injection rate into the dry sample, the fluid was imbibed into the rock uniformly down the length of the core. With increasing injection rates, the flow remained uniform over the core cross section through complete saturation.

  13. Computerized tomographic analysis of fluid flow in fractured tuff

    SciTech Connect (OSTI)

    Felice, C.W.; Sharer, J.C. ); Springer, E.P. )

    1992-01-01

    The purpose of this summary is to demonstrate the usefulness of X-ray computerized tomography to observe fluid flow down a fracture and rock matrix imbibition in a sample of Bandelier tuff. This was accomplished by using a tuff sample 152.4 mm long and 50.8 mm in diameter. A longitudinal fracture was created by cutting the core with a wire saw. The fractured piece was then coupled to its adjacent section to that the fracture was not expected. Water was injected into a dry sample at five flow rates and CT scanning performed at set intervals during the flow. Cross sectional images and longitudinal reconstructions were built and saturation profiles calculated for the sample at each time interval at each flow rate. The results showed that for the test conditions, the fracture was not a primary pathway of fluid flow down the sample. At a slow fluid injection rate into the dry sample, the fluid was imbibed into the rock uniformly down the length of the core. With increasing injection rates, the flow remained uniform over the core cross section through complete saturation.

  14. Investigating the changes in matrix and fracture properties and fluid flow under different stress-state conditions 

    E-Print Network [OSTI]

    Muralidharan, Vivek

    2004-11-15

    The fracture aperture and fracture permeability are usually considered to remain the same during the production life of a naturally fractured reservoir, regardless of the degree of depletion; but reservoirs experience different stress state...

  15. Naturally fractured reservoirs contain a significant amount of the world oil reserves. A number of these reservoirs contain several

    E-Print Network [OSTI]

    Arbogast, Todd

    Summary Naturally fractured reservoirs contain a significant amount of the world oil reserves simulation of naturally fractured reservoirs is one of the most important, challenging, and computationally intensive problems in reservoir engineering. Parallel reservoir simulators developed for naturally fractured

  16. An analytical model for solute transport through a water-saturated single fracture and permeable rock matrix

    E-Print Network [OSTI]

    Houseworth, J.E.

    2014-01-01

    in fractured porous media, Water Resour. Res. , 48, W01542,of parallel fractures, Water Resour. Res. , 18(6), 1634–for a single fracture, Water Resour. Res. , 17(3), 555–564.

  17. A new friction factor correlation for laminar, single-phase flows through rock fractures

    SciTech Connect (OSTI)

    Nazridoust, K. (Clarkson Univ., Potsdam, NY); Ahmadi, G. (Clarkson Univ., Potsdam, NY); Smith, D.H.

    2006-09-30

    Single-phase flow through fractured media occurs in various situations, such as transport of dissolved contaminants through geological strata, sequestration of carbon dioxide in depleted gas reservoirs, and in primary oil recovery. In the present study, fluid flows through a rock fracture were simulated. The fracture geometry was obtained from the CT scans of a rock fracture produced by the Brazilian method in a sandstone sample. A post-processing code using a CAD package was developed and used to generate the three-dimensional fracture from the CT scan data. Several sections along the fracture were considered and the GambitTM code was used to generate unstructured grids for flow simulations. FLUENTTM was used to analyze the flow conditions through the fracture section for different flow rates. Because of the small aperture of the fractures, the gravitational effects could be neglected. It was confirmed that the pressure drop was dominated by the smallest aperture passages of the fracture. The accuracy of parallel plate models for estimating the pressure drops through fractures was studied. It was shown that the parallel plate flow model with the use of an appropriate effective fracture aperture and inclusion of the tortuosity factor could provide reasonable estimates for pressure drops in the fracture. On the basis of the CFD simulation data, a new expression for the friction factor for flows through fractures was developed. The new model predictions were compared with the simulation results and favorable agreement was found. It was shown that when the length of the fracture and the mean and standard deviation of the fracture are known, the pressure loss as a function of the flow rate could be estimated. These findings may prove useful for design of lab experiments, computational studied of flows through real rock fractures, or inclusions in simulators for large-scale flows in highly fractured rocks.

  18. Analysis of Fracture in Cores from the Tuff Confining Unit beneath Yucca Flat, Nevada Test Site

    SciTech Connect (OSTI)

    Lance Prothro

    2008-03-01

    The role fractures play in the movement of groundwater through zeolitic tuffs that form the tuff confining unit (TCU) beneath Yucca Flat, Nevada Test Site, is poorly known. This is an important uncertainty, because beneath most of Yucca Flat the TCU lies between the sources of radionuclide contaminants produced by historic underground nuclear testing and the regional carbonate aquifer. To gain a better understanding of the role fractures play in the movement of groundwater and radionuclides through the TCU beneath Yucca Flat, a fracture analysis focusing on hydraulic properties was performed on conventional cores from four vertical exploratory holes in Area 7 of Yucca Flat that fully penetrate the TCU. The results of this study indicate that the TCU is poorly fractured. Fracture density for all fractures is 0.27 fractures per vertical meter of core. For open fractures, or those observed to have some aperture, the density is only 0.06 fractures per vertical meter of core. Open fractures are characterized by apertures ranging from 0.1 to 10 millimeter, and averaging 1.1 millimeter. Aperture typically occurs as small isolated openings along the fracture, accounting for only 10 percent of the fracture volume, the rest being completely healed by secondary minerals. Zeolite is the most common secondary mineral occurring in 48 percent of the fractures observed.

  19. Borehole deviation surveys are necessary for hydraulic fracture monitoring Leo Eisner, Schlumberger Cambridge Research, Petr Bulant, Charles University in Prague, Jol H. Le Calvez*,

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Borehole deviation surveys are necessary for hydraulic fracture monitoring Leo Eisner, Schlumberger Not performing accurate borehole deviation surveys for hydraulic fracture monitoring (HFM) and neglecting fracture parameters. Introduction Recently a large number of hydraulic fracture treatments have been

  20. High Impact Technology Catalyst: Technology Deployment Strategies...

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

    High Impact Technology Catalyst: Technology Deployment Strategies High Impact Technology Catalyst: Technology Deployment Strategies The Energy Department released the High Impact...

  1. Vehicle Technologies Office: 2014 Electric Drive Technologies...

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

    Vehicle Technologies Office: 2014 Electric Drive Technologies Annual Progress Report Vehicle Technologies Office: 2014 Electric Drive Technologies Annual Progress Report The...

  2. Fracture properties evaluation of stainless steel piping for LBB applications

    SciTech Connect (OSTI)

    Kim, Y.J.; Seok, C.S.; Chang, Y.S. [Sung Kyun Kwan Univ., Suwon (Korea, Republic of)

    1997-04-01

    The objective of this paper is to evaluate the material properties of SA312 TP316 and SA312 TP304 stainless steels and their associated welds manufactured for shutdown cooling line and safety injection line of nuclear generating stations. A total of 82 tensile tests and 58 fracture toughness tests on specimens taken from actual pipes were performed and the effect of various parameters such as the pipe size, the specimen orientation, the test temperature and the welding procedure on the material properties are discussed. Test results show that the effect of the test temperature on the fracture toughness was significant while the effects of the pipe size and the specimen orientation on the fracture toughness were negligible. The material properties of the GTAW weld metal was in general higher than those of the base metal.

  3. Fracture mechanics evaluation for at typical PWR primary coolant pipe

    SciTech Connect (OSTI)

    Tanaka, T. [Kansai Electric Power Company, Osaka (Japan); Shimizu, S.; Ogata, Y. [Mitsubishi Heavy Industries, Ltd., Kobe (Japan)

    1997-04-01

    For the primary coolant piping of PWRs in Japan, cast duplex stainless steel which is excellent in terms of strength, corrosion resistance, and weldability has conventionally been used. The cast duplex stainless steel contains the ferrite phase in the austenite matrix and thermal aging after long term service is known to change its material characteristics. It is considered appropriate to apply the methodology of elastic plastic fracture mechanics for an evaluation of the integrity of the primary coolant piping after thermal aging. Therefore we evaluated the integrity of the primary coolant piping for an initial PWR plant in Japan by means of elastic plastic fracture mechanics. The evaluation results show that the crack will not grow into an unstable fracture and the integrity of the piping will be secured, even when such through wall crack length is assumed to equal the fatigue crack growth length for a service period of up to 60 years.

  4. Technology '90

    SciTech Connect (OSTI)

    Not Available

    1991-01-01

    The US Department of Energy (DOE) laboratories have a long history of excellence in performing research and development in a number of areas, including the basic sciences, applied-energy technology, and weapons-related technology. Although technology transfer has always been an element of DOE and laboratory activities, it has received increasing emphasis in recent years as US industrial competitiveness has eroded and efforts have increased to better utilize the research and development resources the laboratories provide. This document, Technology '90, is the latest in a series that is intended to communicate some of the many opportunities available for US industry and universities to work with the DOE and its laboratories in the vital activity of improving technology transfer to meet national needs. Technology '90 is divided into three sections: Overview, Technologies, and Laboratories. The Overview section describes the activities and accomplishments of the DOE research and development program offices. The Technologies section provides descriptions of new technologies developed at the DOE laboratories. The Laboratories section presents information on the missions, programs, and facilities of each laboratory, along with a name and telephone number of a technology transfer contact for additional information. Separate papers were prepared for appropriate sections of this report.

  5. Spatial statistics for predicting flow through a rock fracture

    SciTech Connect (OSTI)

    Coakley, K.J.

    1989-03-01

    Fluid flow through a single rock fracture depends on the shape of the space between the upper and lower pieces of rock which define the fracture. In this thesis, the normalized flow through a fracture, i.e. the equivalent permeability of a fracture, is predicted in terms of spatial statistics computed from the arrangement of voids, i.e. open spaces, and contact areas within the fracture. Patterns of voids and contact areas, with complexity typical of experimental data, are simulated by clipping a correlated Gaussian process defined on a N by N pixel square region. The voids have constant aperture; the distance between the upper and lower surfaces which define the fracture is either zero or a constant. Local flow is assumed to be proportional to local aperture cubed times local pressure gradient. The flow through a pattern of voids and contact areas is solved using a finite-difference method. After solving for the flow through simulated 10 by 10 by 30 pixel patterns of voids and contact areas, a model to predict equivalent permeability is developed. The first model is for patterns with 80% voids where all voids have the same aperture. The equivalent permeability of a pattern is predicted in terms of spatial statistics computed from the arrangement of voids and contact areas within the pattern. Four spatial statistics are examined. The change point statistic measures how often adjacent pixel alternate from void to contact area (or vice versa ) in the rows of the patterns which are parallel to the overall flow direction. 37 refs., 66 figs., 41 tabs.

  6. Improving Geologic and Engineering Models of Midcontinent Fracture and Karst-Modified Reservoirs Using New 3-D Seismic Attributes

    SciTech Connect (OSTI)

    Susan Nissen; Saibal Bhattacharya; W. Lynn Watney; John Doveton

    2009-03-31

    Our project goal was to develop innovative seismic-based workflows for the incremental recovery of oil from karst-modified reservoirs within the onshore continental United States. Specific project objectives were: (1) to calibrate new multi-trace seismic attributes (volumetric curvature, in particular) for improved imaging of karst-modified reservoirs, (2) to develop attribute-based, cost-effective workflows to better characterize karst-modified carbonate reservoirs and fracture systems, and (3) to improve accuracy and predictiveness of resulting geomodels and reservoir simulations. In order to develop our workflows and validate our techniques, we conducted integrated studies of five karst-modified reservoirs in west Texas, Colorado, and Kansas. Our studies show that 3-D seismic volumetric curvature attributes have the ability to re-veal previously unknown features or provide enhanced visibility of karst and fracture features compared with other seismic analysis methods. Using these attributes, we recognize collapse features, solution-enlarged fractures, and geomorphologies that appear to be related to mature, cockpit landscapes. In four of our reservoir studies, volumetric curvature attributes appear to delineate reservoir compartment boundaries that impact production. The presence of these compartment boundaries was corroborated by reservoir simulations in two of the study areas. Based on our study results, we conclude that volumetric curvature attributes are valuable tools for mapping compartment boundaries in fracture- and karst-modified reservoirs, and we propose a best practices workflow for incorporating these attributes into reservoir characterization. When properly calibrated with geological and production data, these attributes can be used to predict the locations and sizes of undrained reservoir compartments. Technology transfer of our project work has been accomplished through presentations at professional society meetings, peer-reviewed publications, Kansas Geological Survey Open-file reports, Master's theses, and postings on the project website: http://www.kgs.ku.edu/SEISKARST.

  7. Numerical Modeling of Hydraulic Fracture Propagation Using Thermo-hydro-mechanical Analysis with Brittle Damage Model by Finite Element Method 

    E-Print Network [OSTI]

    Min, Kyoung

    2013-07-16

    Better understanding and control of crack growth direction during hydraulic fracturing are essential for enhancing productivity of geothermal and petroleum reservoirs. Structural analysis of fracture propagation and impact ...

  8. F-K Characteristics of the Seismic Response to a Set of Discrete Parallel Fractures

    E-Print Network [OSTI]

    Vetri, Laura

    2006-01-01

    We model seismic wave propagation in a reservoir with discrete fracture zones using a finite difference scheme, which implements the Coates-Schoenberg formulation for fractured media. We study the variation of scattered ...

  9. Geophysical characterization of the effects of fractures and stress on subsurface reservoirs

    E-Print Network [OSTI]

    Fang, Xinding, Ph. D. Massachusetts Institute of Technology

    2013-01-01

    We study the effect of fractures on reservoir characterization and subsurface rock property measurements using seismic data. Based on the scale of a fracture relative to seismic wavelength, we divide the dissertation into ...

  10. Gas Permeability of Fractured Sandstone/Coal Samples under Variable Confining Pressure

    E-Print Network [OSTI]

    Liu, Weiqun; Li, Yushou; Wang, Bo

    2010-01-01

    of Fractured Sandstone/Coal Samples Smeulders, D.M.J. ,stress on permeability of coal. Int. J. Rock Mech. Min. Sci.of Fractured Sandstone/Coal Samples under Variable Con?ning

  11. FRAC-STIM: A Physics-Based Fracture Simulation, /reservoir Flow...

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

    FRAC-STIM: A Physics-Based Fracture Simulation, reservoir Flow and Heat Transport Simulator(aka FALCON) FRAC-STIM: A Physics-Based Fracture Simulation, reservoir Flow and Heat...

  12. Hydraulic fracturing in faulted sedimentary basins: Numerical simulation of potential contamination of shallow aquifers over long

    E-Print Network [OSTI]

    McKenzie, Jeffrey M.

    fracturing (hydrofracturing or ``fracking'') is generally used [BAPE, 2011; EPA, 2012]. Hydraulic fracturing, which returns to the surface [Gregory et al., 2001]. The fracking fluid is commonly composed of $99

  13. Streamline-based simulation of water injection in naturally fractured reservoirs 

    E-Print Network [OSTI]

    Al-Huthali, Ahmed

    2004-09-30

    The current streamline formulation is limited to single-porosity systems and is then not suitable for application to naturally fractured reservoirs. Describing the fluid transport in naturally fractured reservoirs has been ...

  14. Thermo-Poroelastic Fracture Propagation Modeling with Displacement Discontinuity Boundary Element Method 

    E-Print Network [OSTI]

    Chun, Kwang Hee

    2013-08-01

    . The influence of pore pressure and temperature changes on the fracture propagation length and path, as well as on stress and pore pressure distribution near wellbores and fractures, was considered in isotropic and homogeneous rock formations. The BEM used...

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

    E-Print Network [OSTI]

    Zarrin, Tahira

    2014-04-17

    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...

  16. Modeling Acid Transport and Non-Uniform Etching in a Stochastic Domain in Acid Fracturing 

    E-Print Network [OSTI]

    Mou, Jianye

    2010-10-12

    Success of acid fracturing depends on uneven etching along the fracture surfaces caused by heterogeneities such as variations in local mineralogy and variations in leakoff behavior. The heterogeneities tend to create channeling characteristics...

  17. Modeling fluid flow through single fracture using experimental, stochastic, and simulation approaches 

    E-Print Network [OSTI]

    Alfred, Dicman

    2004-09-30

    This research presents an approach to accurately simulate flow experiments through a fractured core using experimental, stochastic, and simulation techniques. Very often, a fracture is assumed as a set of smooth parallel plates separated by a...

  18. Property measurement and correlation for homogeneous and naturally fractured low permeability cores 

    E-Print Network [OSTI]

    Fan, Jin

    1993-01-01

    This thesis presents the results of measurements from ten naturally fractured Devonian Shale cores using a new laboratory technique to determine the distinctive properties of the matrix and the fractures. The new technique is based on a pressure...

  19. The Effect of Proppant Size and Concentration on Hydraulic Fracture Conductivity in Shale Reservoirs 

    E-Print Network [OSTI]

    Kamenov, Anton

    2013-04-11

    Hydraulic fracture conductivity in ultra-low permeability shale reservoirs is directly related to well productivity. The main goal of hydraulic fracturing in shale formations is to create a network of conductive pathways in the rock which increase...

  20. Sensitivity of time lapse seismic data to the compliance of hydraulic fractures

    E-Print Network [OSTI]

    Fang, Xinding

    2013-01-01

    We study the sensitivity of seismic waves to changes in the fracture normal and tangential compliances by analyzing the fracture sensitivity wave equation, which is derived by differentiating the elastic wave equation with ...