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1

Naturally fractured tight gas reservoir detection optimization  

SciTech Connect (OSTI)

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

NONE

1998-09-30T23:59:59.000Z

2

Naturally fractured tight gas reservoir detection optimization  

SciTech Connect (OSTI)

In March, work continued on characterizing probabilities for determining natural fracturing associated with the GGRB for the Upper Cretaceous tight gas plays. Structural complexity, based on potential field data and remote sensing data was completed. A resource estimate for the Frontier and Mesa Verde play was also completed. Further, work was also conducted to determine threshold economics for the play based on limited current production in the plays in the Wamsutter Ridge area. These analyses culminated in a presentation at FETC on 24 March 1999 where quantified natural fracture domains, mapped on a partition basis, which establish ''sweet spot'' probability for natural fracturing, were reviewed. That presentation is reproduced here as Appendix 1. The work plan for the quarter of January 1, 1999--March 31, 1999 comprised five tasks: (1) Evaluation of the GGRB partitions for structural complexity that can be associated with natural fractures, (2) Continued resource analysis of the balance of the partitions to determine areas with higher relative gas richness, (3) Gas field studies, (4) Threshold resource economics to determine which partitions would be the most prospective, and (5) Examination of the area around the Table Rock 4H well.

NONE

1999-04-30T23:59:59.000Z

3

Naturally fractured tight gas reservoir detection optimization  

SciTech Connect (OSTI)

Building upon the partitioning of the Greater Green River Basin (GGRB) that was conducted last quarter, the goal of the work this quarter has been to conclude evaluation of the Stratos well and the prototypical Green River Deep partition, and perform the fill resource evaluation of the Upper Cretaceous tight gas play, with the goal of defining target areas of enhanced natural fracturing. The work plan for the quarter of November 1-December 31, 1998 comprised four tasks: (1) Evaluation of the Green River Deep partition and the Stratos well and examination of potential opportunity for expanding the use of E and P technology to low permeability, naturally fractured gas reservoirs, (2) Gas field studies, and (3) Resource analysis of the balance of the partitions.

NONE

1999-06-01T23:59:59.000Z

4

Naturally fractured tight gas reservoir detection optimization  

SciTech Connect (OSTI)

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

NONE

1998-11-30T23:59:59.000Z

5

Naturally fractured tight gas reservoir detection optimization  

SciTech Connect (OSTI)

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

NONE

1998-11-30T23:59:59.000Z

6

Naturally fractured tight gas reservoir detection optimization. Final report  

SciTech Connect (OSTI)

This DOE-funded research into seismic detection of natural fractures is one of six projects within the DOE`s Detection and Analysis of Naturally Fractured Gas Reservoirs Program, a multidisciplinary research initiative to develop technology for prediction, detection, and mapping of naturally fractured gas reservoirs. The demonstration of successful seismic techniques to locate subsurface zones of high fracture density and to guide drilling orientation for enhanced fracture permeability will enable better returns on investments in the development of the vast gas reserves held in tight formations beneath the Rocky Mountains. The seismic techniques used in this project were designed to capture the azimuthal anisotropy within the seismic response. This seismic anisotropy is the result of the symmetry in the rock fabric created by aligned fractures and/or unequal horizontal stresses. These results may be compared and related to other lines of evidence to provide cross-validation. The authors undertook investigations along the following lines: Characterization of the seismic anisotropy in three-dimensional, P-wave seismic data; Characterization of the seismic anisotropy in a nine-component (P- and S-sources, three-component receivers) vertical seismic profile; Characterization of the seismic anisotropy in three-dimensional, P-to-S converted wave seismic data (P-wave source, three-component receivers); and Description of geological and reservoir-engineering data that corroborate the anisotropy: natural fractures observed at the target level and at the surface, estimation of the maximum horizontal stress in situ, and examination of the flow characteristics of the reservoir.

NONE

1997-11-19T23:59:59.000Z

7

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

SciTech Connect (OSTI)

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

NONE

1997-05-01T23:59:59.000Z

8

Detection and Characterization of Natural and Induced Fractures...  

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

Institute of Technology) Objectives: To combine geophysical methods for reservoir and fracture characterization with rock physics measurements made under in-situ conditions (up to...

9

Detection and Characterization of Natural and Induced Fractures...  

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

Geothermal Systems Project objectives: Combine geophysical methods for reservoir and fracture characterization with rock physics measurements made under in-situ conditions (up to...

10

Detection and Characterization of Natural and Induced Fractures...  

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

RelevanceImpact of Research - Combine geophysical methods for reservoir and fracture characterization with rock physics measurements made under in-situ conditions (up to...

11

Detection and Characterization of Natural and Induced Fractures...  

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

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

12

Naturally fractured tight gas reservoir detection optimization. Quarterly report, January 1, 1997--March 31, 1997  

SciTech Connect (OSTI)

This document contains the quarterly report dated January 1-March 31, 1997 for the Naturally Fractured Tight Gas Reservoir Detection Optimization project. Topics covered in this report include AVOA modeling using paraxial ray tracing, AVOA modeling for gas- and water-filled fractures, 3-D and 3-C processing, and technology transfer material. Several presentations from a Geophysical Applications Workshop workbook, workshop schedule, and list of workshop attendees are also included.

NONE

1998-04-01T23:59:59.000Z

13

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

SciTech Connect (OSTI)

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

NONE

1994-10-01T23:59:59.000Z

14

Hydraulic fracturing in a naturally fractured reservoir  

SciTech Connect (OSTI)

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

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

1994-12-31T23:59:59.000Z

15

Naturally fractured tight gas - gas reservoir detection optimization. Quarterly report, June 1, 1996--September 30, 1996  

SciTech Connect (OSTI)

This document contains the status report for the Naturally Fractured Tight Gas-Gas Reservoir Detection Optimization project for the contract period 9/30/93 to 3/31/97. Data from seismic surveys are analyzed for structural imaging of reflector units. The data were stacked using the new, improved statics and normal moveout velocities. The 3-D basin modeling effort is continuing with code development. The main activities of this quarter were analysis of fluid pressure data, improved sedimentary history, lithologic unit geometry reconstruction algorithm and computer module, and further improvement, verification, and debugging of the basin stress and multi-phase reaction transport module.

Maxwell, J.M.; Ortoleva, P.; Payne, D.; Sibo, W.

1996-11-15T23:59:59.000Z

16

Numerical Investigation of Interaction Between Hydraulic Fractures and Natural Fractures  

E-Print Network [OSTI]

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

Xue, Wenxu

2011-02-22T23:59:59.000Z

17

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

Broader source: Energy.gov [DOE]

Project objectives: Combine geophysical methods for reservoir and fracture characterization with rock physics measurements made under in-situ conditions (up to 350?C) for development of geothermal systems.

18

Simulation of Hydraulic Fractures and their Interactions with Natural Fractures  

E-Print Network [OSTI]

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

Sesetty, Varahanaresh

2012-10-19T23:59:59.000Z

19

Three Models for Water ooding in a Naturally Fractured Petroleum ...  

E-Print Network [OSTI]

THREE MODELS FOR WATERFLOODING IN A NATURALLY. FRACTURED ... 1. Introduction. For the purposes of this paper a naturally fractured reservoir.

20

Characterization of natural fractures in Mesaverde core from the multiwell experiment  

SciTech Connect (OSTI)

Natural fractures dominate the permeability of tight sandstone reservoirs in the Mesaverde Formation of the Piceance Creek Basin, north-western Colorado. Roughly 1900 natural fractures, detected in 4200 ft of Mesaverde core from the US Department of Energy's Multiwell Experiment (MWX), have been differentiated into 10 different fracture types on the basis of fracture morphology, inclination, the presence of slickensides, the presence of dickite mineralization and/or host lithology. Approximately 75% of the MWX core fractures are dewatering planes in mudstone and are probably unimportant to reservoir permeability. The remaining 25% of the MWX core fractures include 275 mostly calcite-mineralized, vertical extension fractures, 61 irregular, dickite-mineralized extension fractures, 27 mostly calcite-mineralized, horizontal extension fractures, and 90 slickensided, occasionally mineralized shear fractures. These extension and shear fractures are all potentially important to reservoir permeability and consequently productivity. 13 refs., 61 figs., 2 tabs.

Finley, S.J.; Lorenz, J.C.

1988-09-01T23:59:59.000Z

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


21

Detecting Fractures Using Technology at High Temperatures and...  

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

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

22

Estimating Major and Minor Natural Fracture Patterns in Gas  

E-Print Network [OSTI]

Estimating Major and Minor Natural Fracture Patterns in Gas Shales Using Production Data Razi Identification of infill drilling locations has been challenging with mixed results in gas shales. Natural fractures are the main source of permeability in gas shales. Natural fracture patterns in shale has a random

Mohaghegh, Shahab

23

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

24

Integration of well test analysis into naturally fractured reservoir simulation  

E-Print Network [OSTI]

of the requirements for the degree of MASTER OF SCIENCE December 2005 Major Subject: Petroleum Engineering INTEGRATION OF WELL TEST ANALYSIS INTO A NATURALLY FRACTURED RESERVOIR SIMULATION A Thesis by LAURA..., W. John Lee Wayne M. Ahr Head of Department, Stephen A. Holditch December 2005 Major Subject: Petroleum Engineering iii ABSTRACT Integration of Well Test Analysis into a Naturally Fractured Reservoir...

Perez Garcia, Laura Elena

2006-04-12T23:59:59.000Z

25

Simulation of naturally fractured reservoirs using empirical transfer function  

E-Print Network [OSTI]

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...

Tellapaneni, Prasanna Kumar

2004-09-30T23:59:59.000Z

26

Streamline-based production data integration in naturally fractured reservoirs  

E-Print Network [OSTI]

Streamline-based models have shown great potential in reconciling high resolution geologic models to production data. In this work we extend the streamline-based production data integration technique to naturally fractured reservoirs. We use a...

Al Harbi, Mishal H.

2005-08-29T23:59:59.000Z

27

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

SciTech Connect (OSTI)

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

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

1997-08-01T23:59:59.000Z

28

AVO in azmuthally anisotropic media fracture detection using P ...  

E-Print Network [OSTI]

An enormous amount of natural gas exists in naturally fractured, low-permeability reservoirs. ..... 4.5.4 Center frequencies of pre-stack data . . . . . . . . . . . . . . . 110 .... U.S. energy policy, natural gas may emerge as an alternative fossil fuel to oil.

Wei Chen

29

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

SciTech Connect (OSTI)

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.

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

1997-08-01T23:59:59.000Z

30

Naturally fractured tight gas reservoir detection optimization  

SciTech Connect (OSTI)

During this quarter, work began on the regional structural and geologic analysis of the greater Green River basin (GGRB) in southwestern Wyoming, northwestern Colorado and northeastern Utah. The ultimate objective of the regional analysis is to apply the techniques developed and demonstrated during earlier phases of the project to sweet-spot delineation in a relatively new and underexplored play: tight gas from continuous-type Upper Cretaceous reservoirs of the GGRB. The primary goal of this work is to partition and high-grade the greater Green River basin for exploration efforts in the Cretaceous tight gas play. The work plan for the quarter of January 1, 1998--March 31, 1998 consisted of three tasks: (1) Acquire necessary data and develop base map of study area; (2) Process data for analysis; and (3) Initiate structural study. The first task and second tasks were completed during this reporting period. The third task was initiated and work continues.

NONE

1998-09-30T23:59:59.000Z

31

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

E-Print Network [OSTI]

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...

Fan, Jin

2012-06-07T23:59:59.000Z

32

Signal processing of Shiley heart valve data for fracture detection  

SciTech Connect (OSTI)

Given digital acoustic data emanating from the heart sounds of the beating heart measured from laboratory sheep with implanted Bjoerk-Shiley Convexo-Concave heart valves, it is possible to detect and extract the opening and closing heart beats from the data. Once extracted, spectral or other information can then obtained from the heartbeats and passed on to feature extraction algorithms, neutral networks, or pattern recognizers so that the valve condition, either fractured or intact, may be determined.

Mullenhoff, C.

1993-04-01T23:59:59.000Z

33

Signal processing of Shiley heart valve data for fracture detection  

SciTech Connect (OSTI)

Given digital acoustic data emanating from the heart sounds of the beating heart measured from laboratory sheep with implanted Bjoerk-Shiley Convexo-Concave heart valves, it is possible to detect and extract the opening and closing heart beats from the data. Once extracted, spectral or other information can then obtained from the heartbeats and passed on to feature extraction algorithms, neural networks, or pattern recognizers so that the valve condition, either fractured or intact, may be determined.

Mullenhoff, C.

1993-09-01T23:59:59.000Z

34

3.3 NUMERICAL MODELING OF SOLID DEFORMATION AND STRESS-DEPENDENT PERMEABILITY IN NATURALLY FRACTURED  

E-Print Network [OSTI]

permeability. When the pore pressure depletes due to oil/gas production rates in highly stress FRACTURED RESERVOIRS During the first year of this project, we analyzed the productivity behavior was demonstrated. 3.3.1 Introduction Fractures are the main fluid flow paths in naturally fractured reservoirs

Schechter, David S.

35

Mathematical and Statistical Investigation of Steamflooding in Naturally Fractured Carbonate Heavy Oil Reservoirs.  

E-Print Network [OSTI]

??A significant amount of Viscous Oil (e.g., heavy oil, extra heavy oil, and bitumen) is trapped in Naturally Fractured Carbonate Reservoirs also known as NFCRs.… (more)

Shafiei, Ali

2013-01-01T23:59:59.000Z

36

EVALUATION OF PERFORMANCE OF CYCLIC STEAM INJECTION IN NATURALLY FRACTURED RESERVOIRS – AN ARTIFICIAL NEURAL NETWORK APPLICATION.  

E-Print Network [OSTI]

??With increasing demand on oil, it is important to improve the recovery factor of oil reservoirs. Naturally fractured reservoirs constitute a major portion of world’s… (more)

Chintalapati, Santosh Phani Bhushan

2011-01-01T23:59:59.000Z

37

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

E-Print Network [OSTI]

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

Kim, Tae Hyung

2009-05-15T23:59:59.000Z

38

Detecting Fractures Using Technology at High Temperatures and...  

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

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

39

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

SciTech Connect (OSTI)

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.

Not Available

1991-10-01T23:59:59.000Z

40

Hairline Fracture Detection using MRF and Gibbs Sampling A. S. Chowdhury1  

E-Print Network [OSTI]

Hairline Fracture Detection using MRF and Gibbs Sampling A. S. Chowdhury1 , A. Bhattacharya2 , S. M of hairline fractures, representing points or ar- eas of discontinuity in the bone, is a clinically handle unknown local degradation in the image. A novel two-phase scheme for hairline mandibular fracture

Bhandarkar, Suchendra "Suchi" M.

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


41

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

E-Print Network [OSTI]

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

Stanford University

42

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

SciTech Connect (OSTI)

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

R. L. Billingsley; V. Kuuskraa

2006-03-31T23:59:59.000Z

43

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

SciTech Connect (OSTI)

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.

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

2002-12-31T23:59:59.000Z

44

3 RESERVOIR PERFORMANCE ANALYSIS 3.1 ANALYSIS OF IMBIBITION MECHANISM IN THE NATURALLY FRACTURED  

E-Print Network [OSTI]

recovery mechanism in the West Texas Spraberry reservoir is evaluated. Waterflood recovery in the Spraberry waterflooding is performed in this type of reservoir, the intent is to fill the fractures with water to initiate89 3 RESERVOIR PERFORMANCE ANALYSIS 3.1 ANALYSIS OF IMBIBITION MECHANISM IN THE NATURALLY FRACTURED

Schechter, David S.

45

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

SciTech Connect (OSTI)

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

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

2010-04-01T23:59:59.000Z

46

Type curve analysis for naturally fractured reservoirs (infinite-acting reservoir case): a new approach  

E-Print Network [OSTI]

analysis methods are sometimes inconclusive for pressure transient analysis of wells completed in naturally fractured reservoirs. This is due to wellbore storage effects which mask the early time "straight-line" that is expected on the semilog plot...

Angel Restrepo, Juan Alejandro

2012-06-07T23:59:59.000Z

47

Application of computed tomography to enhanced oil recovery studies in naturally fractured reservoirs  

E-Print Network [OSTI]

digital imaging technology with Nuclear Magnetic Resonance Imaging. Research Objectives The objectives of this research are: ~ Investigation of the process of imbibition in naturally fractured reservoirs as an EOR technique. ~ Apply the use of COz...

Fineout, James Mark

1992-01-01T23:59:59.000Z

48

STUDY OF WATERFLOODING PROCESS IN NATURALLY FRACTURED RESERVOIRS FROM STATIC AND DYNAMIC IMBIBITION EXPERIMENTS  

E-Print Network [OSTI]

STUDY OF WATERFLOODING PROCESS IN NATURALLY FRACTURED RESERVOIRS FROM STATIC AND DYNAMIC IMBIBITION experiments, followed by waterflooding, were performed at reservoir conditions to investigate rock wettability Berea and Spraberry cores at reservoir conditions to illustrate the actual process of waterflooding

Schechter, David S.

49

Modeling effects of diffusion and gravity drainage on oil recovery in naturally fractured reservoirs under gas injection  

E-Print Network [OSTI]

Gas injection in naturally fractured reservoirs maintains the reservoir pressure, and increases oil recovery primarily by gravity drainage and to a lesser extent by mass transfer between the flowing gas in the fracture and the porous matrix...

Jamili, Ahmad

2010-04-22T23:59:59.000Z

50

INVESTIGATION OF EFFICIENCY IMPROVEMENTS DURING CO2 INJECTION IN HYDRAULICALLY AND NATURALLY FRACTURED RESERVOIRS  

SciTech Connect (OSTI)

This report describes the work performed during the second year of the project, ''Investigating of Efficiency Improvements during CO{sub 2} Injection in Hydraulically and Naturally Fractured Reservoirs.'' The objective of this project is to perform unique laboratory experiments with artificial fractured cores (AFCs) and X-ray CT to examine the physical mechanisms of bypassing in HFR and NFR that eventually result in less efficient CO{sub 2} flooding in heterogeneous or fracture-dominated reservoirs. To achieve this objective, in this period we concentrated our effort on investigating the effect of CO{sub 2} injection rates in homogeneous and fractured cores on oil recovery and a strategy to mitigate CO{sub 2} bypassing in a fractured core.

David S. Schechter

2004-04-26T23:59:59.000Z

51

INVESTIGATION OF EFFICIENCY IMPROVEMENTS DURING CO2 INJECTION IN HYDRAULICALLY AND NATURALLY FRACTURED RESERVOIRS  

SciTech Connect (OSTI)

This report describes the work performed during the second year of the project, ''Investigating of Efficiency Improvements during CO{sub 2} Injection in Hydraulically and Naturally Fractured Reservoirs.'' The objective of this project is to perform unique laboratory experiments with artificial fractured cores (AFCs) and X-ray CT to examine the physical mechanisms of bypassing in HFR and NFR that eventually result in less efficient CO{sub 2} flooding in heterogeneous or fracture-dominated reservoirs. To achieve this objective, in this period we concentrated our effort on modeling the fluid flow in fracture surface, examining the fluid transfer mechanisms and describing the fracture aperture distribution under different overburden pressure using X-ray CT scanner.

David S. Schechter

2003-10-01T23:59:59.000Z

52

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

E-Print Network [OSTI]

finite difference method to solve the fluid flow in fractures, a fully coupled displacement discontinuity method to build the global relation of fracture deformation, and the Barton-Bandis model of fracture deformation to build the local relation...

Tao, Qingfeng

2010-07-14T23:59:59.000Z

53

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

SciTech Connect (OSTI)

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

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

2004-05-01T23:59:59.000Z

54

INVESTIGATION OF EFFICIENCY IMPROVEMENTS DURING CO2 INJECTION IN HYDRAULICALLY AND NATURALLY FRACTURED RESERVOIRS  

SciTech Connect (OSTI)

This report describes the work performed during the third year of the project, ''Investigating of Efficiency Improvements during CO{sub 2} Injection in Hydraulically and Naturally Fractured Reservoirs.'' The objective of this project is to perform unique laboratory experiments with artificial fractured cores (AFCs) and X-ray CT to examine the physical mechanisms of bypassing in HFR and NFR that eventually result in more efficient CO{sub 2} flooding in heterogeneous or fracture-dominated reservoirs. To achieve this objective, in this period we concentrated our effort on modeling fluid flow through rough fractures and investigating the grid orientation effect in rectangular grid blocks particularly at high mobility ratio as our precursor to use a compositional simulator. We are developing a robust simulator using Voronoi grids to accurately represent natural and induced fractures. We are also verifying the accuracy of the simulation using scaled laboratory experiments to provide a benchmark for our simulation technique. No such simulator currently exists so this capability will represent a major breakthrough in simulation of gas injection in fractured systems. The following sections outline the results that appear in this report.

David S. Schechter

2004-10-10T23:59:59.000Z

55

Natural and Induced Fracture Diagnostics from 4-D VSP Low Permeability Gas Reservoirs  

SciTech Connect (OSTI)

Tight gas sand reservoirs generally contain thick gas-charged intervals that often have low porosity and very low permeability. Natural and induced fractures provide the only means of production. The objective of this work is to locate and characterize natural and induced fractures from analysis of scattered waves recorded on 4-D (time lapse) VSP data in order to optimize well placement and well spacing in these gas reservoirs. Using model data simulating the scattering of seismic energy from hydraulic fractures, we first show that it is possible to characterize the quality of fracturing based upon the amount of scattering. In addition, the picked arrival times of recorded microseismic events provide the velocity moveout for isolating the scattered energy on the 4-D VSP data. This concept is applied to a field dataset from the Jonah Field in Wyoming to characterize the quality of the induced hydraulic fractures. The time lapse (4D) VSP data from this field are imaged using a migration algorithm that utilizes shot travel time tables derived from the first breaks of the 3D VSPs and receiver travel time tables based on the microseismic arrival times and a regional velocity model. Four azimuthally varying shot tables are derived from picks of the first breaks of over 200 VSP records. We create images of the fracture planes through two of the hydraulically fractured wells in the field. The scattered energy shows correlation with the locations of the microseismic events. In addition, the azimuthal scattering is different from the azimuthal reflectivity of the reservoir, giving us more confidence that we have separated the scattered signal from simple formation reflectivity. Variation of the scattered energy along the image planes suggests variability in the quality of the fractures in three distinct zones.

Mark E. Willis; Daniel R. Burns; M. Nafi Toksoz

2008-09-30T23:59:59.000Z

56

A Parallelizable Method for Two-Phase Flows in Naturally-Fractured ...  

E-Print Network [OSTI]

Mar 27, 2002 ... ooding a naturally-fractured petroleum reservoir or to unsaturated ..... Finally, it is necessary to de ne the initial status of the entire system; it is su cient to ...... In Figure 12 we report the results of an investigation of the e ect of ...

2002-03-27T23:59:59.000Z

57

Advanced reservoir characterization and evaluation of CO2 gravity drainage in the naturally fractured Spraberry Trend Area. Annual report, September 1, 1996--August 31, 1997  

SciTech Connect (OSTI)

The objective of the Spraberry CO{sub 2} pilot project is to determine the technical and economic feasibility of continuous CO{sub 2} injection in the naturally fractured reservoirs of the Spraberry Trend. In order to describe, understand, and model CO{sub 2} flooding in the naturally fractured Spraberry reservoirs, characterization of the fracture system is a must. Additional reservoir characterization was based on horizontal coring in the second year of the project. In addition to characterization of natural fractures, horizontal coring has confirmed a previously developed rock model for describing the Spraberry Trend shaly sands. A better method for identifying Spraberry pay zones has been verified. The authors have completed the reservoir characterization, which includes matrix description and detection (from core-log integration) and fracture characterization. This information is found in Section 1. The authors have completed extensive imbibition experiments that strongly indicate that the weakly water-wet behavior of the reservoir rock may be responsible for poor waterflood response observed in many Spraberry fields. The authors have also made significant progress in analytical and numerical simulation of performance in Spraberry reservoirs as seen in Section 3. They have completed several suites of CO{sub 2} gravity drainage in Spraberry and Berea whole cores at reservoir conditions and reported in Section 4. The results of these experiments have been useful in developing a model for free-fall gravity drainage and have validated the premise that CO{sub 2} will recover oil from tight, unconfined Spraberry matrix.

McDonald, P.

1998-06-01T23:59:59.000Z

58

INVESTIGATION OF EFFICIENCY IMPROVEMENTS DURING CO2 INJECTION IN HYDRAULICALLY AND NATURALLY FRACTURED RESERVOIRS  

SciTech Connect (OSTI)

The objective of this project is to perform unique laboratory experiments with artificial fractured cores (AFCs) and X-ray CT to examine the physical mechanisms of bypassing in HFR and NFR that eventually result in more efficient CO{sub 2} flooding in heterogeneous or fracture-dominated reservoirs. To achieve this objective, we divided the report into two chapters. The first chapter was to image and perform experimental investigation of transfer mechanisms during CO{sub 2} flooding in NFR and HFR using X-ray CT scanner. In this chapter, we emphasized our work on understanding the connection between fracture properties and fundamentals of transfer mechanism from matrix to fractures and fluid flow through fracture systems. We started our work by investigating the effect of different overburden pressures and stress-state conditions on rock properties and fluid flow. Since the fracture aperture is one of important parameter that governs the fluid flow through the fracture systems, the average fracture aperture from the fluid flow experiments and fracture aperture distribution derived from X-ray CT scan were estimated for our modeling purposes. The fracture properties and fluid flow have significant changes in response to different overburden pressures and stress-state conditions. The fracture aperture distribution follows lognormal distribution even at elevated stress conditions. Later, we also investigated the fluid transfers between matrix and fracture that control imbibition process. We evaluated dimensionless time for validating the scheme of upscaling laboratory experiments to field dimensions. In CO{sub 2} injection experiments, the use of X-ray CT has allowed us to understand the mechanisms of CO{sub 2} flooding process in fractured system and to take important steps in reducing oil bypassed. When CO{sub 2} flooding experiments were performed on a short core with a fracture at the center of the core, the gravity plays an important role in the recovery of oil even in a short matrix block. This results are contrary with the previous believes that gravity drainage has always been associated with tall matrix blocks. In order to reduce oil bypassed, we injected water that has been viscosified with a polymer into the fracture to divert CO{sub 2} flow into matrix and delay CO{sub 2} breakthrough. Although the breakthrough time reduced considerably, water ''leak off'' into the matrix was very high. A cross-linked gel was used in the fracture to avoid this problem. The gel was found to overcome ''leak off'' problems and effectively divert CO{sub 2} flow into the matrix. As part of our technology transfer activity, we investigated the natural fracture aperture distribution of Tensleep formation cores. We found that the measured apertures distributions follow log normal distribution as expected. The second chapter deals with analysis and modeling the laboratory experiments and fluid flow through fractured networks. We derived a new equation to determine the average fracture aperture and the amount of each flow through fracture and matrix system. The results of this study were used as the observed data and for validating the simulation model. The idea behind this study is to validate the use of a set of smooth parallel plates that is common in modeling fracture system. The results suggest that fracture apertures need to be distributed to accurately model the experimental results. In order to study the imbibition process in details, we developed imbibition simulator. We validated our model with X-ray CT experimental data from different imbibition experiments. We found that the proper simulation model requires matching both weight gain and CT water saturation simultaneously as oppose to common practices in matching imbibition process with weight gain only because of lack information from CT scan. The work was continued by developing dual porosity simulation using empirical transfer function (ETF) derived from imbibition experiments. This allows reduction of uncertainty parameter in modeling transfer of fluids from matrix to the fra

David S. Schechter

2005-09-28T23:59:59.000Z

59

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

E-Print Network [OSTI]

IN-SITU REMEDIATION OF NATURALLY OCCURRING RADIOACTIVE MATERIALS WITH HIGH-PERMEABILITY HYDRAULIC FRACTURING A Thesis by ANDRONIKOS STAVROS DEMARCHOS Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... 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 Approved as to style and content by: Michael J. Economides (Chair of Committee) ulat D. Mamora (Member...

Demarchos, Andronikos Stavros

1998-01-01T23:59:59.000Z

60

Integrated Approach to Use Natural Chemical and Isotopic Tracers to Estimate Fracture Spacing and Surface Area in EGS Systems  

Broader source: Energy.gov [DOE]

DOE Geothermal Peer Review 2010 - Presentation. This objective of this project is to develop an innovative approach to estimate fracture surface area and spacing through interpretation of signals of natural chemical and isotopic tracers.

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


61

Modeling Wettability Alteration using Chemical EOR Processes in Naturally Fractured Reservoirs  

SciTech Connect (OSTI)

The objective of our search is to develop a mechanistic simulation tool by adapting UTCHEM to model the wettability alteration in both conventional and naturally fractured reservoirs. This will be a unique simulator that can model surfactant floods in naturally fractured reservoir with coupling of wettability effects on relative permeabilities, capillary pressure, and capillary desaturation curves. The capability of wettability alteration will help us and others to better understand and predict the oil recovery mechanisms as a function of wettability in naturally fractured reservoirs. The lack of a reliable simulator for wettability alteration means that either the concept that has already been proven to be effective in the laboratory scale may never be applied commercially to increase oil production or the process must be tested in the field by trial and error and at large expense in time and money. The objective of Task 1 is to perform a literature survey to compile published data on relative permeability, capillary pressure, dispersion, interfacial tension, and capillary desaturation curve as a function of wettability to aid in the development of petrophysical property models as a function of wettability. The new models and correlations will be tested against published data. The models will then be implemented in the compositional chemical flooding reservoir simulator, UTCHEM. The objective of Task 2 is to understand the mechanisms and develop a correlation for the degree of wettability alteration based on published data. The objective of Task 3 is to validate the models and implementation against published data and to perform 3-D field-scale simulations to evaluate the impact of uncertainties in the fracture and matrix properties on surfactant alkaline and hot water floods.

Mojdeh Delshad; Gary A. Pope; Kamy Sepehrnoori

2007-09-30T23:59:59.000Z

62

Fracture detection in crystalline rock using ultrasonic reflection techniques: Volume 1  

SciTech Connect (OSTI)

This research was initiated to investigate using ultrasonic seismic reflection techniques to detect fracture discontinuities in a granitic rock. Initial compressional (P) and shear (SH) wave experiments were performed on a 0.9 {times} 0.9 {times} 0.3 meter granite slab in an attempt to detect seismic energy reflected from the opposite face of the slab. It was found that processing techniques such as deconvolution and array synthesis could improve the standout of the reflection event. During the summers of 1979 and 1980 SH reflection experiments were performed at a granite quarry near Knowles, California. The purpose of this study was to use SH reflection methods to detect an in situ fracture located one to three meters behind the quarry face. These SH data were later analyzed using methods similar to those applied in the laboratory. Interpretation of the later-arriving events observed in the SH field data as reflections from a steeply-dipping fracture was inconclusive. 41 refs., 43 figs., 7 tabs.

Palmer, S.P. (Lawrence Berkeley Lab., CA (USA))

1982-11-01T23:59:59.000Z

63

Combining a New 3-D Seismic S-Wave Propagation Analysis for Remote Fracture Detection with a Robust Subsurface  

E-Print Network [OSTI]

Combining a New 3-D Seismic S-Wave Propagation Analysis for Remote Fracture Detection with a Robust. This report culminates Phase 2 of the study, Combining a New 3-D Seismic S-Wave Propagation Analysis

Texas at Austin, University of

64

This paper was prepared for presentation at the 2002 Naturally Fractured Reservoir Conference held in Oklahoma City, 34 June 2003.  

E-Print Network [OSTI]

This paper was prepared for presentation at the 2002 Naturally Fractured Reservoir Conference held-acre CO2 pilot in the Spraberry Trend Area in west Texas. Spraberry reservoirs originally contained 10 Bbbls OOIP of which less than 10% has been recovered. Waterflooding has been documented as a poor

Schechter, David S.

65

This paper was prepared for presentation at the 2002 Naturally Fractured Reservoir Conference held in Oklahoma City, 34 June 2003.  

E-Print Network [OSTI]

This paper was prepared for presentation at the 2002 Naturally Fractured Reservoir Conference held reservoir developed at the late 1940's with a history of low productivity and low recovery. It has been shown over the years that conventional waterflooding is highly ineffective in this field due

Schechter, David S.

66

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

E-Print Network [OSTI]

Summary Naturally fractured reservoirs contain a significant amount of the world oil reserves. A number of these reservoirs contain several billion barrels of oil. Accurate and efficient reservoir this implementation has led to a unique and powerful reservoir simulator that can be used by small and large oil

Arbogast, Todd

67

Fracture, aging and disease in bone  

E-Print Network [OSTI]

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

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

2006-01-01T23:59:59.000Z

68

Dynamic Reservoir Characterization Of Naturally Fractured Reservoirs From An Inter-Well Tracer Test  

E-Print Network [OSTI]

After field redevelopment in the Sherrod Unit of the Spraberry Trend Area, an inter-well tracer test was conducted at the field scale in order to understand the fracture system, which forms preferential flow paths for better management...

Kilicaslan, Ufuk

2013-12-03T23:59:59.000Z

69

INVESTIGATION OF EFFICIENCY IMPROVEMENTS DURING CO2 INJECTION IN HYDRAULICALLY AND NATURALLY FRACTURED RESERVOIRS  

SciTech Connect (OSTI)

The objective of this project is to perform unique laboratory experiments with artificial fractured cores (AFCs) and X-ray CT to examine the physical mechanisms of bypassing in HFR and NFR that eventually result in less efficient CO{sub 2} flooding in heterogeneous or fracture-dominated reservoirs. This report provides results of the second semi-annual technical progress report that consists of three different topics. In the first topic, laboratory experiments were performed on a Berea core to investigate the changes in rock properties and fluid flow under different stress-state conditions. A comparative study of different stress conditions was also conducted to analyze the effect of the various loading systems. The experimental results show that fracture permeability reduces significantly as the stress increases compared to matrix permeability. The hydrostatic and triaxial stresses have greater impacts on permeability reduction compared to applying stress in the uniaxial stress condition. Fracture flow dominates when the applied stress is less, however, the matrix flow rate increases as applied stress increases and dominates at high stress even if the fracture does not heal completely. In the second topic, the preliminary results of static imbibition experiments are presented as a precursor to image the saturation profiles using X-Ray CT scanner. The static and dynamic imbibition experiments have been done previously (Schechter et al, 2002). The imaging of imbibition experiment is underway to track the saturation profiles using X-ray CT scanner. Hence, no more conclusions are drawn from this study at this time. In the last topic, the modeling of fluid flow through a single fracture incorporating the effect of surface roughness is conducted. Fracture permeability is usually estimated by a cubic law that is based on the theory of hydrodynamics for the laminar flow between flat plates. However, the cubic law is too simple to estimate the fracture permeability correctly, because the surface of real fracture is much more complicated and rougher than the surface of flat plate. Several researchers have shown that the flow characteristics of an actual fracture surface would be quite different due to the effect of tortuosity, impact of surface roughness and contact areas. Nonetheless, to date, these efforts have not converged to form a unified definition on the fracture aperture needed in the cubic law. In this study, therefore, we show that the cubic law could still be used to model small-scale and field-scale data as long as it is modeled effectively, accounting for the effect of surface roughness associated with the fracture surface. The goal of this research is to examine the effect of surface roughness for flow through fractures and to effectively incorporate them into simulations with the aid of geostatistics. Since the research has been supported with experimental results, the consistency of the results enabled us to define a methodology for single fracture simulation. This methodology successfully modeled the slow rate and pressure drop from fractured core experiments, which were earlier not possible through parallel plate approach. Observations suggest that the fracture aperture needs to be distributed to accurately model the experimental results. The effect of friction and tortuosity due to surface roughness needs to be taken into account while modeling.

David S. Schechter

2002-10-30T23:59:59.000Z

70

Investigation of Efficiency Improvements During CO2 Injection in Hydraulically and Naturally Fractured Reservoirs  

SciTech Connect (OSTI)

The objective of this project was to perform unique laboratory experiments with artificial fractured cores (AFCs) and X-ray CT to examine the physical mechanisms of bypassing in HFR and NFR that eventually result in less efficient CO2 flooding in heterogeneous or fracture-dominated reservoirs. This report provided results of the second semi-annual technical progress report that consists of three different topics.

Schechter, David S.; Vance, Harold

2003-03-10T23:59:59.000Z

71

Remote laser detection of natural gas leakages from pipelines  

SciTech Connect (OSTI)

A differential absorption lidar based on a tunable TEA CO{sub 2} laser emitting at 42 lines of the 'hot' 01{sup 1}1 - 11{sup 1}0 band in the range from 10.9 to 11.4 {mu}m is developed for detecting natural gas leakages from oil pipelines by measuring the ethane content in the atmosphere. The ethane detection sensitivity is 0.9 ppm km. The presence of methane does not distort the measurement results. The developed lidar can detect the natural gas leakage from kilometre heights at the flying velocities up to 200 km h{sup -1} and a probe pulse repetition rate of 5 Hz. (laser applications and other topics in quantum electronics)

Petukhov, V O; Gorobets, V A [B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk (Belarus); Andreev, Yu M [Institute of Monitoring of Climatic and Ecological Systems, Siberian Division of the Russian Academy of Sciences, Tomsk (Russian Federation); Lanskii, G V

2010-02-28T23:59:59.000Z

72

Innovative Methodology for Detection of Fracture-Controlled Sweet Spots in the Northern Appalachian Basin  

SciTech Connect (OSTI)

For two consecutive years, 2004 and 2005, the largest natural gas well (in terms of gas flow/day) drilled onshore USA targeted the Ordovician Trenton/Black River (T/BR) play in the Appalachian Basin of New York State (NYS). Yet, little data were available concerning the characteristics of the play, or how to recognize and track T/BR prospects across the region. Traditional exploration techniques for entry into a hot play were of limited use here, since existing deep well logs and public domain seismic were almost non-existent. To help mitigate this problem, this research project was conceived with two objectives: (1) to demonstrate that integrative traditional and innovative techniques could be used as a cost-effective reconnaissance exploration methodology in this, and other, areas where existing data in targeted fracture-play horizons are almost non-existent, and (2) determine critical characteristics of the T/BR fields. The research region between Seneca and Cayuga lakes (in the Finger Lakes of NYS) is on strike and east of the discovery fields, and the southern boundary of the field area is about 8 km north of more recently discovered T/BR fields. Phase I, completed in 2004, consisted of integrating detailed outcrop fracture analyses with detailed soil gas analyses, lineaments, stratigraphy, seismic reflection data, well log data, and aeromagnetics. In the Seneca Lake region, Landsat lineaments (EarthSat, 1997) were coincident with fracture intensification domains (FIDs) and minor faults observed in outcrop and inferred from stratigraphy. Soil gas anomalies corresponded to ENE-trending lineaments and FIDs. N- and ENE-trending lineaments were parallel to aeromagnetic anomalies, whereas E-trending lineaments crossed aeromagnetic trends. 2-D seismic reflection data confirmed that the E-trending lineaments and FIDs occur where shallow level Alleghanian salt-cored thrust-faulted anticlines occur. In contrast, the ENE-trending FIDs and lineaments occur where Iapetan rift faults have been episodically reactivated, and a few of these faults extend through the entire stratigraphic section. The ENE-trending faults and N-striking transfer zones controlled the development of the T/BR grabens. In both the Seneca Lake and Cayuga Lake regions, we found more FIDs than Landsat lineaments, both in terms of individual FIDs and trends of FIDs. Our fused Landsat/ASTER image provided more lineaments, but the structural framework inferred from these lineaments is incomplete even for the fused image. Individual lineaments may not predict surface FIDs (within 500m). However, an individual lineament that has been groundtruthed by outcrop FIDs can be used as a proxy for the trend of intense fracturing. Aeromagnetics and seismic reflection data across the discovery fields west of Keuka Lake demonstrate that the fields terminate on the east against northerly-striking faults that extend from Precambrian basement to, in some cases, the surface; the fields terminate in the west at N- and NW-striking faults. Seismic and well log data show that the fields must be compartmentalized, since different parts of the same field show different histories of development. T/BR fields south of the research area also terminate (on the east) against northerly-trending lineaments which we suggest mark faults. Phase II, completed in 2006, consisted of collection and analysis of an oriented, horizontal core retrieved from one of the T/BR fields in a graben south of the field area. The field is located along ENE-trending EarthSat (1997) lineaments, similar to that hypothesized for the study area. The horizontal core shows much evidence for reactivation along the ENE-trending faults, with multiple events of vein development and both horizontal and vertical stylolite growth. Horizontal veins that post- and pre-date other vein sets indicate that at least two orogenic phases (separated by unloading) affected vein development. Many of the veins and releasing bend features (rhombochasms) are consistent with strike-slip motion (oblique) along ENE-striking faults as a result

Robert Jacobi; John Fountain; Stuart Loewenstein; Edward DeRidder; Bruce Hart

2007-03-31T23:59:59.000Z

73

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

SciTech Connect (OSTI)

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

Robert Jacobi; John Fountain

2002-06-30T23:59:59.000Z

74

Advanced Reservoir Characterization and Evaluation of CO2 Gravity Drainage in the Naturally Fractured Spraberry Trend Area, Class III  

SciTech Connect (OSTI)

The goal of this project was to assess the economic feasibility of CO2 flooding the naturally fractured Spraberry Trend Area in west Texas. This objective was accomplished through research in four areas: (1) extensive characterization of the reservoirs, (2) experimental studies of crude oil/brine/rock (COBR) interactions in the reservoirs, (3) reservoir performance analysis, and (4) experimental investigations on CO2 gravity drainage in Spraberry whole cores. This provides results of the final year of the six-year project for each of the four areas.

Knight, Bill; Schechter, David S.

2002-07-26T23:59:59.000Z

75

Advanced Reservoir Characterization and Evaluation of CO{sub 2} Gravity Drainage in the Naturally Fractured Spraberry Trend Area  

SciTech Connect (OSTI)

The overall goal of this project is to assess the economic feasibility of CO{sub 2} flooding the naturally fractured Spraberry Trend Area in West Texas. This objective is being accomplished by conducting research in four areas: (1) extensive characterization of the reservoirs, (2) experimental studies of crude oil/brine/rock (COBR) interactions in the reservoirs, (3) reservoir performance analysis, and, (4) experimental investigations on CO2 gravity drainage in Spraberry whole cores. This report provides results of the third year of the five-year project for each of the four areas including a status report of field activities leading up to injection of CO2.

Schechter, D.S.

1999-02-03T23:59:59.000Z

76

Flashback Detection Sensor for Hydrogen Augmented Natural Gas Combustion  

SciTech Connect (OSTI)

The use of hydrogen augmented fuel is being investigated by various researchers as a method to extend the lean operating limit, and potentially reduce thermal NOx formation in natural gas fired lean premixed (LPM) combustion systems. The resulting increase in flame speed during hydrogen augmentation, however, increases the propensity for flashback in LPM systems. Real-time in-situ monitoring of flashback is important for the development of control strategies for use of hydrogen augmented fuel in state-of-the-art combustion systems, and for the development of advanced hydrogen combustion systems. The National Energy Technology Laboratory (NETL) and Woodward Industrial Controls are developing a combustion control and diagnostics sensor (CCADS), which has already been demonstrated as a useful sensor for in-situ monitoring of natural gas combustion, including detection of important combustion events such as flashback and lean blowoff. Since CCADS is a flame ionization sensor technique, the low ion concentration produced in pure hydrogen combustion raises concerns of whether CCADS can be used to monitor flashback in hydrogen augmented combustion. This paper discusses CCADS tests conducted at 0.2-0.6 MPa (2-6 atm), demonstrating flashback detection with fuel compositions up to 80% hydrogen (by volume) mixed with natural gas. NETL’s Simulation Validation (SimVal) combustor offers full optical access to pressurized combustion during these tests. The CCADS data and high-speed video show the reaction zone moves upstream into the nozzle as the hydrogen fuel concentration increases, as is expected with the increased flame speed of the mixture. The CCADS data and video also demonstrate the opportunity for using CCADS to provide the necessary in-situ monitor to control flashback and lean blowoff in hydrogen augmented combustion applications.

Thornton, J.D.; Chorpening, B.T.; Sidwell, T.; Strakey, P.A.; Huckaby, E.D.; Benson, K.J. (Woodward)

2007-05-01T23:59:59.000Z

77

Advanced reservoir characterization and evaluation of CO{sub 2} gravity drainage in the naturally fractured Spraberry Trend Area. Annual report, September 1, 1996--August 31, 1997  

SciTech Connect (OSTI)

The overall goal of this project is to assess the economic feasibility of CO{sub 2} flooding the naturally fractured Spraberry Trend Area in West Texas. This objective is being accomplished by conducting research in four areas: (1) extensive characterization of the reservoirs, (2) experimental studies of crude oil/brine/rock (COBR) interaction in the reservoirs, (3) reservoir performance analysis, and (4) experimental investigations on CO{sub 2} gravity drainage in Spraberry whole cores. This report provides results of the second year of the five-year project for each of the four areas. In the first area, the author has completed the reservoir characterization, which includes matrix description and detection (from core-log integration) and fracture characterization. This information is found in Section 1. In the second area, the author has completed extensive inhibition experiments that strongly indicate that the weakly water-wet behavior of the reservoir rock may be responsible for poor waterflood response observed in many Spraberry fields. In the third area, the author has made significant progress in analytical and numerical simulation of performance in Spraberry reservoirs as seen in Section 3. In the fourth area, the author has completed several suites of CO{sub 2} gravity drainage in Spraberry and Berea whole cores at reservoir conditions and reported in Section 4. The results of these experiments have been useful in developing a model for free-fall gravity drainage and have validated the premise that CO{sub 2} will recover oil from tight, unconfined Spraberry matrix. The final three years of this project involves implementation of the CO{sub 2} pilot. Up to twelve new wells are planned in the pilot area; water injection wells to contain the CO{sub 2}, three production wells to monitor performance of CO{sub 2}, CO{sub 2} injection wells including one horizontal injection well and logging observation wells to monitor CO{sub 2} flood fronts. Results of drilling these wells will be forthcoming.

Schechter, D.S.

1998-07-01T23:59:59.000Z

78

Naturally fractured tight gas reservoir detection optimization. Quarterly report, April 1--June 30, 1995  

SciTech Connect (OSTI)

This progress report discusses in details the geologic assessment of the Piceance Creek Basin. Analysis of the high resolution aeromagnetic survey concentrated on the high-resolution aeromagnetic data acquired by World Geoscience, but the interpretation was supplemented by examination of regional published gravity and magnetic data, as well as surface geology and subsurface geology.

NONE

1995-07-31T23:59:59.000Z

79

Advanced reservoir characterization and evaluation of CO{sub 2} gravity drainage in the naturally fractured Spraberry Reservoir. Quarterly technical report, January 1--March 31, 1996  

SciTech Connect (OSTI)

The objective of this research and the pilot project planned is to test the feasibility of CO{sub 2} for recovering oil from the naturally fractured Spraberry Trend Area in the Midland Basin. This notoriously marginal reservoir has confounded operators for 40 years with rapid depletion, low recovery during primary, disappointing waterflood results and low ultimate recovery. Yet, the tremendous areal coverage and large amount of remaining oil (up to 10 Bbbl) warrants further investigation to expend all possible process options before large numbers of Spraberry wellbores need to be plugged and abandoned. CO{sub 2} injection on a continuous, pattern-wide basis has not been attempted in the Spraberry Trend. This is due to the obvious existence of a network of naturally-occurring fractures. However, it has become clear in recent years that neglecting CO{sub 2} injection as an option in fractured reservoirs may overlook potential projects which may be viable. The 15-well pilot field demonstration and supporting research will provide the necessary information to quantify the conditions whereby CO{sub 2} flooding would be economic in the Spraberry Trend.

Schechter, D.

1996-07-01T23:59:59.000Z

80

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]

Poland self-sufficient in natural gas?", which will be published in final form in a special issue-4296 Can hydraulic fracturing make Poland self-sufficient in natural gas? Kjell Alekletta,b,* , Tadeusz to be able to replace gas from Russia with domestic natural gas production and eventually to become self

Patzek, Tadeusz W.

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


81

Fracture Blisters  

E-Print Network [OSTI]

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

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

2011-01-01T23:59:59.000Z

82

MULTI-PHASE FRACTURE-MATRIX INTERACTIONS UNDER STRESS CHANGES  

SciTech Connect (OSTI)

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

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

2002-10-28T23:59:59.000Z

83

Simulation of fluid flow mechanisms in high permeability zones (Super-K) in a giant naturally fractured carbonate reservoir  

E-Print Network [OSTI]

and fractures were treated as two systems. Reservoir management practices and decisions should be very carefully reviewed and executed in this dual continuum reservoir based on the results of this work. Studying this dual media flow behavior is vital for better...

Abu-Hassoun, Amer H.

2009-05-15T23:59:59.000Z

84

Advanced reservoir characterization and evaluation of CO{sub 2} gravity drainage in the naturally fractured Spraberry Trend Area. Annual report, September 1, 1995--August 31, 1996  

SciTech Connect (OSTI)

The overall goal of this project is to assess the economic feasibility of CO{sub 2} flooding in the naturally fractured Spraberry Trend Area in West Texas. This objective is being accomplished by conducting research in four areas: (1) extensive characterization of the reservoirs, (2) experimental studies of crude oil/brine/rock (COBR) interaction in the reservoirs, (3) analytical and numerical simulation of Spraberry reservoirs, and, (4) experimental investigations on CO{sub 2} gravity drainage in Spraberry whole cores. This report provides results of the first year of the five-year project for each of the four areas.

Schechter, D.S.

1997-12-01T23:59:59.000Z

85

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

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

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

86

Fracture Evolution Following a Hydraulic Stimulation within an...  

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

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

87

Tectonic Setting and Characteristics of Natural Fractures in MesaVerde and Dakota Reservoirs of the San Juan Basin  

SciTech Connect (OSTI)

The Cretaceous strata that fill the San Juan Basin of northwestern New Mexico and southwestern Colorado were shortened in a generally N-S to NN13-SSW direction during the Laramide orogeny. This shortening was the result of compression of the strata between southward indentation of the San Juan Uplift at the north edge of the basin and northward to northeastward indentation of the Zuni Uplift from the south. Right-lateral strike-slip motion was concentrated at the eastern and western basin margins of the basin to form the Hogback Monocline and the Nacimiento Uplift at the same time, and small amounts of shear may have been pervasive within the basin as well. Vertical extension fractures, striking N-S to NNE-SSW with local variations (parallel to the Laramide maximum horizontal compressive stress), formed in both Mesaverde and Dakota sandstones under this system, and are found in outcrops and in the subsurface of the San Juan Basin. The immature Mesaverde sandstones typically contain relatively long, irregular, vertical extension fractures, whereas the quartzitic Dakota sandstones contain more numerous, shorter, sub-parallel, closely spaced, extension fractures. Conjugate shear planes in several orientations are also present locally in the Dakota strata.

LORENZ,JOHN C.; COOPER,SCOTT P.

2000-12-20T23:59:59.000Z

88

Fracture induced anisotropy in viscoelastic UNLP, 11 Octubre de 2012  

E-Print Network [OSTI]

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

Santos, Juan

89

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

E-Print Network [OSTI]

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

Lu, Zhiming

90

Fluid Flow Simulation in Fractured Reservoirs  

E-Print Network [OSTI]

The purpose of this study is to analyze fluid flow in fractured reservoirs. In most petroleum reservoirs, particularly carbonate reservoirs and some tight sands, natural fractures play a critical role in controlling fluid ...

Sarkar, Sudipta

2002-01-01T23:59:59.000Z

91

Field tests of probes for detecting internal corrosion of natural gas transmission pipelines  

SciTech Connect (OSTI)

A field study was conducted to evaluate the use of electrochemical corrosion rate (ECR) probes for detecting corrosion in environments similar to those found in natural gas transmission pipelines. Results and interpretation will be reported from four different field tests. Flange and flush-mount probes were used in four different environments at a gas-gathering site and one environment but two different orientations at a natural gas plant. These sites were selected to represent normal and upset conditions in a gas transmission pipeline. The environments consisted of 2 different levels of humidified natural gas/organic/water mixtures removed from natural gas, and the environments at the 6 and 12 o'clock positions of a natural gas pipeline carrying 2-phase gas/liquid flow. Data are also presented comparing the ECR probe data to that for coupons used to determine corrosion rate and to detect the presence of microbiologically influenced corrosion (MIC).

Covino, Bernard S., Jr.; Bullard, Sophie J.; Cramer, Stephen D.; Holcomb, Gordon R.; Ziomek-Moroz, M.; Cayard, Michael S. (Intercorr International Inc.); Kane, Russell D. (Intercorr International Inc.); Meidinger, Brian (RMOTC-DOE)

2005-01-01T23:59:59.000Z

92

Advanced Reservoir Characterization and Evaluation of CO{sub 2} Gravity Drainage in the Naturally Fractured Spraberry Trend Area, Class III  

SciTech Connect (OSTI)

The goal of this project was to assess the economic feasibility of CO{sub 2} flooding the naturally fractured Spraberry Trend Area in west Texas. This objective was accomplished through research in four areas: (1) extensive characterization of the reservoirs, (2) experimental studies of crude oil/brine/rock (COBR) interactions in the reservoirs, (3) reservoir performance analysis, and (4) experimental investigations on CO{sub 2} gravity drainage in Spraberry whole cores. The four areas have been completed and reported in the previous annual reports. This report provides the results of the final year of the project including two SPE papers (SPE 71605 and SPE 71635) presented in the 2001 SPE Annual Meeting in New Orleans, two simulation works, analysis of logging observation wells (LOW) and progress of CO{sub 2} injection.

Knight, Bill; Schechter, David S.

2001-11-19T23:59:59.000Z

93

Flight Testing of an Advanced Airborne Natural Gas Leak Detection System  

SciTech Connect (OSTI)

ITT Industries Space Systems Division (Space Systems) has developed an airborne natural gas leak detection system designed to detect, image, quantify, and precisely locate leaks from natural gas transmission pipelines. This system is called the Airborne Natural Gas Emission Lidar (ANGEL) system. The ANGEL system uses a highly sensitive differential absorption Lidar technology to remotely detect pipeline leaks. The ANGEL System is operated from a fixed wing aircraft and includes automatic scanning, pointing system, and pilot guidance systems. During a pipeline inspection, the ANGEL system aircraft flies at an elevation of 1000 feet above the ground at speeds of between 100 and 150 mph. Under this contract with DOE/NETL, Space Systems was funded to integrate the ANGEL sensor into a test aircraft and conduct a series of flight tests over a variety of test targets including simulated natural gas pipeline leaks. Following early tests in upstate New York in the summer of 2004, the ANGEL system was deployed to Casper, Wyoming to participate in a set of DOE-sponsored field tests at the Rocky Mountain Oilfield Testing Center (RMOTC). At RMOTC the Space Systems team completed integration of the system and flew an operational system for the first time. The ANGEL system flew 2 missions/day for the duration for the 5-day test. Over the course of the week the ANGEL System detected leaks ranging from 100 to 5,000 scfh.

Dawn Lenz; Raymond T. Lines; Darryl Murdock; Jeffrey Owen; Steven Stearns; Michael Stoogenke

2005-10-01T23:59:59.000Z

94

Apple detection in natural tree canopies from multimodal images J. P. Wachs1,2  

E-Print Network [OSTI]

1 Apple detection in natural tree canopies from multimodal images J. P. Wachs1,2 , H. I. Stern2 , T apples within a tree canopy using infra-red and color images in order to achieve automated harvesting. Infra-red provides clues regarding the physical structure and location of the apples based

Wachs, Juan

95

AIRBORNE, OPTICAL REMOTE SENSNG OF METHANE AND ETHANE FOR NATURAL GAS PIPELINE LEAK DETECTION  

SciTech Connect (OSTI)

Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. The scope of the work involved designing and developing an airborne, optical remote sensor capable of sensing methane and, if possible, ethane for the detection of natural gas pipeline leaks. Flight testing using a custom dual wavelength, high power fiber amplifier was initiated in February 2005. Ophir successfully demonstrated the airborne system, showing that it was capable of discerning small amounts of methane from a simulated pipeline leak. Leak rates as low as 150 standard cubic feet per hour (scf/h) were detected by the airborne sensor.

Jerry Myers

2005-04-15T23:59:59.000Z

96

Monitoring hydraulic fracture growth: Laboratory experiments  

SciTech Connect (OSTI)

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

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

2000-04-01T23:59:59.000Z

97

Hydraulic Fracturing (Vermont)  

Broader source: Energy.gov [DOE]

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

98

EXTENDED PERFORMANCE HANDHELD AND MOBILE SENSORS FOR REMOTE DETECTION OF NATURAL GAS LEAKS  

SciTech Connect (OSTI)

This report summarizes work performed by Physical Sciences Inc. (PSI) to advance the state-of-the-art of surveying for leaks of natural gas from transmission and distribution pipelines. The principal project goal was to develop means of deploying on an automotive platform an improved version of the handheld laser-based standoff natural gas leak detector previously developed by PSI and known as the Remote Methane Leak Detector or RMLD. A laser beam which interrogates the air for methane is projected from a spinning turret mounted upon a van. As the van travels forward, the laser beam scans an arc to the front and sides of the van so as to survey across streets and to building walls from a moving vehicle. When excess methane is detected within the arc, an alarm is activated. In this project, we built and tested a prototype Mobile RMLD (MRMLD) intended to provide lateral coverage of 10 m and one lateral scan for every meter of forward motion at forward speeds up to 10 m/s. Using advanced detection algorithms developed as part of this project, the early prototype MRMLD, installed on the back of a truck, readily detected simulated gas leaks of 50 liters per hour. As a supplement to the originally planned project, PSI also participated in a DoE demonstration of several gas leak detection systems at the Rocky Mountain Oilfield Testing Center (RMOTC) during September 2004. Using a handheld RMLD upgraded with the advanced detection algorithms developed in this project, from within a moving vehicle we readily detected leaks created along the 7.4 mile route of a virtual gas transmission pipeline.

Michael B. Frish; B. David Green; Richard T. Wainner; Francesca Scire-Scappuzzo; Paul Cataldi; Matthew C. Laderer

2005-05-01T23:59:59.000Z

99

Fractured shale reservoirs: Towards a realistic model  

SciTech Connect (OSTI)

Fractured shale reservoirs are fundamentally unconventional, which is to say that their behavior is qualitatively different from reservoirs characterized by intergranular pore space. Attempts to analyze fractured shale reservoirs are essentially misleading. Reliance on such models can have only negative results for fractured shale oil and gas exploration and development. A realistic model of fractured shale reservoirs begins with the history of the shale as a hydrocarbon source rock. Minimum levels of both kerogen concentration and thermal maturity are required for effective hydrocarbon generation. Hydrocarbon generation results in overpressuring of the shale. At some critical level of repressuring, the shale fractures in the ambient stress field. This primary natural fracture system is fundamental to the future behavior of the fractured shale gas reservoir. The fractures facilitate primary migration of oil and gas out of the shale and into the basin. In this process, all connate water is expelled, leaving the fractured shale oil-wet and saturated with oil and gas. What fluids are eventually produced from the fractured shale depends on the consequent structural and geochemical history. As long as the shale remains hot, oil production may be obtained. (e.g. Bakken Shale, Green River Shale). If the shale is significantly cooled, mainly gas will be produced (e.g. Antrim Shale, Ohio Shale, New Albany Shale). Where secondary natural fracture systems are developed and connect the shale to aquifers or to surface recharge, the fractured shale will also produce water (e.g. Antrim Shale, Indiana New Albany Shale).

Hamilton-Smith, T. [Applied Earth Science, Lexington, KY (United States)

1996-09-01T23:59:59.000Z

100

A Cost Effective Multi-Spectral Scanner for Natural Gas Detection  

SciTech Connect (OSTI)

The objective of this project is to design, fabricate and demonstrate a cost effective, multi-spectral scanner for natural gas leak detection in transmission and distribution pipelines. During the first year of the project, a laboratory version of the multi-spectral scanner was designed, fabricated, and tested at EnUrga Inc. The multi-spectral scanner was also evaluated using a blind Department of Energy study at the Rocky Mountain Oilfield Testing Center. The performance of the scanner was inconsistent during the blind study. However, most of the leaks were outside the view of the multi-spectral scanner that was developed during the first year of the project. Therefore, a definite evaluation of the capability of the scanner was not obtained. Despite the results, sufficient number of plumes was detected fully confirming the feasibility of the multi-spectral scanner. During the second year, the optical design of the scanner was changed to improve the sensitivity of the system. Laboratory tests show that the system can reliably detect small leaks (20 SCFH) at 30 to 50 feet. A prototype scanner was built and evaluated during the second year of the project. Only laboratory evaluations were completed during the second year. The laboratory evaluations show the feasibility of using the scanner to determine natural gas pipeline leaks. Further field evaluations and optimization of the scanner are required before commercialization of the scanner can be initiated.

Yudaya Sivathanu; Jongmook Lim; Vinoo Narayanan; Seonghyeon Park

2005-12-07T23:59:59.000Z

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


101

Efficient Geomechanical Simulations of Large-Scale Naturally Fractured Reservoirs Using the Fast Multipole-Displacement Discontinuity Method (FM-DDM)  

E-Print Network [OSTI]

Geothermal and unconventional reservoirs play an important role in supplying fuel for a growing energy demand in the United States. The development of such reservoirs relies on creating a fracture network to provide flow and transport conduits...

Verde Salas, Alexander José

2014-04-28T23:59:59.000Z

102

Hydraulic fracturing-1  

SciTech Connect (OSTI)

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

Not Available

1990-01-01T23:59:59.000Z

103

theoretical and applied fracture  

E-Print Network [OSTI]

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

Cizelj, Leon

104

Effective fracture geometry obtained with large water sand ratio  

E-Print Network [OSTI]

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

Kumar, Amrendra

2009-05-15T23:59:59.000Z

105

Seismic characterization of fractured reservoirs by focusing Gaussian beams  

E-Print Network [OSTI]

Naturally fractured reservoirs occur worldwide, and they account for the bulk of global oil production. The most important impact of fractures is their influence on fluid flow. To maximize oil production, the characterization ...

Zheng, Yingcai

106

A Bayesian framework for fracture characterization from surface seismic data  

E-Print Network [OSTI]

We describe a methodology for quantitatively characterizing the fractured nature of a hydrocarbon or geothermal reservoir from surface seismic data under a Bayesian inference framework. Fractures provide pathways for fluid ...

Zamanian, S. Ahmad

2012-01-01T23:59:59.000Z

107

Fracture Characterization from Scattered Energy: A Case Study  

E-Print Network [OSTI]

We use 3D surface seismic data to determine the presence and the preferred orientation of fracture corridors in a field. The Scattering Index method is proving to be a robust tool for detecting and mapping fracture corridors. ...

Grandi, Samantha K.

2006-01-01T23:59:59.000Z

108

Relative Permeability of Fractured Rock  

SciTech Connect (OSTI)

Contemporary understanding of multiphase flow through fractures is limited. Different studies using synthetic fractures and various fluids have yielded different relative permeability-saturation relations. This study aimed to extend the understanding of multiphase flow by conducting nitrogen-water relative permeability experiments on a naturally-fractured rock from The Geysers geothermal field. The steady-state approach was used. However, steady state was achieved only at the endpoint saturations. Several difficulties were encountered that are attributed to phase interference and changes in fracture aperture and surface roughness, along with fracture propagation/initiation. Absolute permeabilities were determined using nitrogen and water. The permeability values obtained change with the number of load cycles. Determining the absolute permeability of a core is especially important in a fractured rock. The rock may change as asperities are destroyed and fractures propagate or st rain harden as the net stresses vary. Pressure spikes occurred in water a solute permeability experiments. Conceptual models of an elastic fracture network can explain the pressure spike behavior. At the endpoint saturations the water relative permeabilities obtained are much less than the nitrogen gas relative permeabilities. Saturations were determined by weighing and by resistivity calculations. The resistivity-saturation relationship developed for the core gave saturation values that differ by 5% from the value determined by weighing. Further work is required to complete the relative permeability curve. The steady-state experimental approach encountered difficulties due to phase interference and fracture change. Steady state may not be reached until an impractical length of time. Thus, unsteady-state methods should be pursued. In unsteady-state experiments the challenge will be in quantifying rock fracture change in addition to fluid flow changes.

Mark D. Habana

2002-06-30T23:59:59.000Z

109

Multi-Attribute Seismic/Rock Physics Approach to Characterizing Fractured Reservoirs  

SciTech Connect (OSTI)

Most current seismic methods to seismically characterize fractures in tight reservoirs depend on a few anisotropic wave propagation signatures that can arise from aligned fractures. While seismic anisotropy can be a powerful fracture diagnostic, a number of situations can lessen its usefulness or introduce interpretation ambiguities. Fortunately, laboratory and theoretical work in rock physics indicates that a much broader spectrum of fracture seismic signatures can occur, including a decrease in P- and S-wave velocities, a change in Poisson's ratio, an increase in velocity dispersion and wave attenuation, as well as well as indirect images of structural features that can control fracture occurrence. The goal of this project was to demonstrate a practical interpretation and integration strategy for detecting and characterizing natural fractures in rocks. The approach was to exploit as many sources of information as possible, and to use the principles of rock physics as the link among seismic, geologic, and log data. Since no single seismic attribute is a reliable fracture indicator in all situations, the focus was to develop a quantitative scheme for integrating the diverse sources of information. The integrated study incorporated three key elements: The first element was establishing prior constraints on fracture occurrence, based on laboratory data, previous field observations, and geologic patterns of fracturing. The geologic aspects include analysis of the stratigraphic, structural, and tectonic environments of the field sites. Field observations and geomechanical analysis indicates that fractures tend to occur in the more brittle facies, for example, in tight sands and carbonates. In contrast, strain in shale is more likely to be accommodated by ductile flow. Hence, prior knowledge of bed thickness and facies architecture, calibrated to outcrops, are powerful constraints on the interpreted fracture distribution. Another important constraint is that fracturing is likely to be more intense near faults--sometimes referred to as the damaged zone. Yet another constraint, based on world-wide observations, is that the maximum likely fracture density increases with depth in a well-defined way. Defining these prior constrains has several benefits: they lead to a priori probability distributions of fractures, that are important for objective statistical integration; they limit the number of geologic hypotheses that need to be theoretically modeled; they provide plausible models for fracture distributions below the seismic resolution. The second element was theoretical rock physics modeling of optimal seismic attributes, including offset and azimuth dependence of traveltime, amplitude, and impedance signatures of anisotropic fractured rocks. The suggested workflow is to begin with an elastic earth model, based on well logs, theoretically add fractures to the likely facies as defined by the geologic prior information, and then compute synthetic seismic traces and attributes, including variations in P and S-wave velocities, Poisson's ratio, reflectivity, travel time, attenuation, and anisotropies of these parameters. This workflow is done in a Monte-Carlo fashion, yielding ranges of expected fracture signatures, and allowing realistic assessments of uncertainty to be honored. The third element was statistical integration of the geophysical data and prior constraints to map fracture intensity and orientations, along with uncertainties. A Bayesian framework was developed that allowed systematic integration of the prior constraints, the theoretical relations between fractures and their seismic signatures, and the various observed seismic observations. The integration scheme was successfully applied on an East Texas field site. The primary benefit from the study was the optimization and refinement of practical workflows for improved geophysical characterization of natural fractures and for quantifying the uncertainty of these interpretations. By presenting a methodology for integrating various types of information, the workflow will

Gary Mavko

2004-11-30T23:59:59.000Z

110

Hydraulic fracturing in tight, fissured media  

SciTech Connect (OSTI)

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

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

1991-02-01T23:59:59.000Z

111

AIRBORNE, OPTICAL REMOTE SENSING OF METHANE AND ETHANE FOR NATURAL GAS PIPELINE LEAK DETECTION  

SciTech Connect (OSTI)

Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. This six-month technical report summarizes the progress for each of the proposed tasks, discusses project concerns, and outlines near-term goals. Ophir has completed a data survey of two major natural gas pipeline companies on the design requirements for an airborne, optical remote sensor. The results of this survey are disclosed in this report. A substantial amount of time was spent on modeling the expected optical signal at the receiver at different absorption wavelengths, and determining the impact of noise sources such as solar background, signal shot noise, and electronic noise on methane and ethane gas detection. Based upon the signal to noise modeling and industry input, Ophir finalized the design requirements for the airborne sensor, and released the critical sensor light source design requirements to qualified vendors. Responses from the vendors indicated that the light source was not commercially available, and will require a research and development effort to produce. Three vendors have responded positively with proposed design solutions. Ophir has decided to conduct short path optical laboratory experiments to verify the existence of methane and absorption at the specified wavelength, prior to proceeding with the light source selection. Techniques to eliminate common mode noise were also evaluated during the laboratory tests. Finally, Ophir has included a summary of the potential concerns for project success and has established future goals.

Jerry Myers

2003-05-13T23:59:59.000Z

112

Natural Gas | Department of Energy  

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

Fossil Natural Gas Natural Gas September 15, 2014 NETL Releases Hydraulic Fracturing Study The National Energy Technology Laboratory has released a technical report on the...

113

Development of Integrated Online Monitoring Systems for Detection of Diversion at Natural Uranium Conversion Facilities  

SciTech Connect (OSTI)

Recent work at Oak Ridge National Laboratory (ORNL) has focused on some source term modeling of uranyl nitrate (UN) as part of a comprehensive validation effort employing gamma-ray detector instrumentation for the detection of diversion from declared conversion activities. Conversion, the process by which natural uranium ore (yellowcake) is purified and converted through a series of chemical processes into uranium hexafluoride gas (UF6), has historically been excluded from the nuclear safeguards requirements of the 235U-based nuclear fuel cycle. The undeclared diversion of this product material could potentially provide feedstock for a clandestine weapons program for state or non-state entities. Given the changing global political environment and the increased availability of dual-use nuclear technology, the International Atomic Energy Agency has evolved its policies to emphasize safeguarding this potential feedstock material in response to dynamic and evolving potential diversion pathways. To meet the demand for instrumentation testing at conversion facilities, ORNL developed the Uranyl Nitrate Calibration Loop Equipment (UNCLE) facility to simulate the full-scale operating conditions of a purified uranium-bearing aqueous stream exiting the solvent extraction process in a natural uranium conversion plant. This work investigates gamma-ray signatures of UN circulating in the UNCLE facility and evaluates detector instrumentation sensitivity to UN for safeguards applications. These detector validation activities include assessing detector responses to the UN gamma-ray signatures for spectrometers based on sodium iodide, lanthanum bromide, and germanium detectors. The results of measurements under static and dynamic operating conditions at concentrations ranging from 10-90g U/L of naturally enriched UN will be presented. A range of gamma-ray lines was examined and self-attenuation factors were calculated, in addition to attenuation for transmission measurement of density, concentration and enrichment. A detailed uncertainty analysis will be presented providing insights into instrumentation limitations to spoofing.

Dewji, Shaheen A [ORNL] [ORNL; Lee, Denise L [ORNL] [ORNL; Croft, Stephen [ORNL] [ORNL; McElroy, Robert Dennis [ORNL] [ORNL; Hertel, Nolan [Georgia Institute of Technology] [Georgia Institute of Technology; Chapman, Jeffrey Allen [ORNL] [ORNL; Cleveland, Steven L [ORNL] [ORNL

2013-01-01T23:59:59.000Z

114

Advanced reservoir characterization and evaluation of CO{sub 2} gravity drainage in the naturally fractured Spraberry Trend Area. First annual technical progress report, September 1, 1995--August 31, 1996  

SciTech Connect (OSTI)

The overall goal of this project is to assess the economic feasibility of CO{sub 2} flooding the naturally fractured Spraberry Trend Area in West Texas. This objective is being accomplished by conducting research in four areas: (1) extensive characterization of the reservoirs, (2) experimental studies of crude oil/brine/rock (COBR) interaction in the reservoirs, (3) analytical and numerical simulation of Spraberry reservoirs, and, (4) experimental investigations on CO{sub 2} gravity drainage in Spraberry whole cores. This report provides results of the first year of the five-year project for each of the four areas.

Schechter, D.S.

1996-12-17T23:59:59.000Z

115

Naturally fractured reservoirs: Optimized E and P strategies using a reaction-transport-mechanical simulator in an integrated approach. Annual report, 1996--1997  

SciTech Connect (OSTI)

The methodology and results of this project are being tested using the Andector-Goldsmith Field in the Permian Basin, West Texas. The study area includes the Central Basin Platform and the Midland Basin. The Andector-Goldsmith Field lies at the juncture of these two zones in the greater West Texas Permian Basin. Although the modeling is being conducted in this area, the results have widespread applicability to other fractured carbonate and other reservoirs throughout the world.

Hoak, T.; Jenkins, R. [Science Applications International Corp., McLean, VA (United States); Ortoleva, P.; Ozkan, G.; Shebl, M.; Sibo, W.; Tuncay, K. [Laboratory for Computational Geodynamics (United States); Sundberg, K. [Phillips Petroleum Company (United States)

1998-07-01T23:59:59.000Z

116

Fracture Properties From Seismic Scattering  

E-Print Network [OSTI]

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

Burns, Daniel R.

2007-01-01T23:59:59.000Z

117

Seismic characterization of fractures  

E-Print Network [OSTI]

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

JM Carcione

2014-06-07T23:59:59.000Z

118

AIRBORNE, OPTICAL REMOTE SENSING OF METHANE AND ETHANE FOR NATURAL GAS PIPLINE LEAK DETECTION  

SciTech Connect (OSTI)

Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. The third six-month technical report contains a summary of the progress made towards finalizing the design and assembling the airborne, remote methane and ethane sensor. The vendor has been chosen and is on contract to develop the light source with the appropriate linewidth and spectral shape to best utilize the Ophir gas correlation software. Ophir has expanded upon the target reflectance testing begun in the previous performance period by replacing the experimental receiving optics with the proposed airborne large aperture telescope, which is theoretically capable of capturing many times more signal return. The data gathered from these tests has shown the importance of optimizing the fiber optic receiving fiber to the receiving optic and has helped Ophir to optimize the design of the gas cells and narrowband optical filters. Finally, Ophir will discuss remaining project issues that may impact the success of the project.

Jerry Myers

2004-05-12T23:59:59.000Z

119

AIRBORNE, OPTICAL REMOTE SENSING OF METHANE AND ETHANE FOR NATURAL GAS PIPELINE LEAK DETECTION  

SciTech Connect (OSTI)

Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. This second six-month technical report summarizes the progress made towards defining, designing, and developing the hardware and software segments of the airborne, optical remote methane and ethane sensor. The most challenging task to date has been to identify a vendor capable of designing and developing a light source with the appropriate output wavelength and power. This report will document the work that has been done to identify design requirements, and potential vendors for the light source. Significant progress has also been made in characterizing the amount of light return available from a remote target at various distances from the light source. A great deal of time has been spent conducting laboratory and long-optical path target reflectance measurements. This is important since it helps to establish the overall optical output requirements for the sensor. It also reduces the relative uncertainty and risk associated with developing a custom light source. The data gathered from the optical path testing has been translated to the airborne transceiver design in such areas as: fiber coupling, optical detector selection, gas filters, and software analysis. Ophir will next, summarize the design progress of the transceiver hardware and software development. Finally, Ophir will discuss remaining project issues that may impact the success of the project.

Jerry Myers

2003-11-12T23:59:59.000Z

120

MULTI-PHASE FRACTURE-MATRIX INTERACTIONS UNDER STRESS CHANGES  

SciTech Connect (OSTI)

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

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

2005-06-15T23:59:59.000Z

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


121

Fracture-Flow-Enhanced Solute Diffusion into Fractured Rock  

E-Print Network [OSTI]

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

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

2008-01-01T23:59:59.000Z

122

Detecting internal corrosion of natural gas transmission pipelines: field tests of probes and systems for real-time corrosion measurement  

SciTech Connect (OSTI)

A field study was conducted to evaluate the use of automated, multi-technique electrochemical corrosion-rate monitoring devices and probes for detecting corrosion in environments similar to those found in natural gas transmission pipelines. It involved measurement of real-time corrosion signals from operating pipelines. Results and interpretation were reported from four different field test locations. Standard flush-mount and custom flange probes were used in four different environments at a gas-gathering site and one environment but two different probe orientations at a natural gas site. These sites were selected to represent normal and upset conditions common in gas transmission pipelines. The environments consisted of two different levels of humidified natural gas, liquid hydrocarbon, and water from natural gas. Probe locations included the 6 and 12 o?clock positions of a natural gas pipeline carrying 2-phase gas/liquid flow. The probe data was monitored using completely remote solar powered systems that provided real-time data transmission via wireless back to a pipeline control station. Data are also presented comparing the ECR probe data to that for coupons used to determine corrosion rate and to detect the presence of microbiologically influenced corrosion (MIC).

Covino, Bernard S., Jr.; Bullard, Sophie J.; Cramer, Stephen D.; Holcomb, Gordon R.; Ziomek-Moroz, M.; Kane, R.D. (InterCorr International); Meidinger, B. (Rocky Mountain Oilfield Testing Center)

2005-01-01T23:59:59.000Z

123

FRACTURED PETROLEUM RESERVOIRS  

SciTech Connect (OSTI)

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

Abbas Firoozabadi

1999-06-11T23:59:59.000Z

124

A Thermoelastic Hydraulic Fracture Design Tool for Geothermal Reservoir Development  

SciTech Connect (OSTI)

Geothermal energy is recovered by circulating water through heat exchange areas within a hot rock mass. Geothermal reservoir rock masses generally consist of igneous and metamorphic rocks that have low matrix permeability. Therefore, cracks and fractures play a significant role in extraction of geothermal energy by providing the major pathways for fluid flow and heat exchange. Thus, knowledge of conditions leading to formation of fractures and fracture networks is of paramount importance. Furthermore, in the absence of natural fractures or adequate connectivity, artificial fracture are created in the reservoir using hydraulic fracturing. At times, the practice aims to create a number of parallel fractures connecting a pair of wells. Multiple fractures are preferred because of the large size necessary when using only a single fracture. Although the basic idea is rather simple, hydraulic fracturing is a complex process involving interactions of high pressure fluid injections with a stressed hot rock mass, mechanical interaction of induced fractures with existing natural fractures, and the spatial and temporal variations of in-situ stress. As a result it is necessary to develop tools that can be used to study these interactions as an integral part of a comprehensive approach to geothermal reservoir development, particularly enhanced geothermal systems. In response to this need we have set out to develop advanced thermo-mechanical models for design of artificial fractures and rock fracture research in geothermal reservoirs. These models consider the significant hydraulic and thermo-mechanical processes and their interaction with the in-situ stress state. Wellbore failure and fracture initiation is studied using a model that fully couples poro-mechanical and thermo-mechanical effects. The fracture propagation model is based on a complex variable and regular displacement discontinuity formulations. In the complex variable approach the displacement discontinuities are defined from the numerical solution of a complex hypersingular integral equation written for a given fracture configuration and loading. The fracture propagation studies include modeling interaction of induced fractures with existing discontinuities such as faults and joints. In addition to the fracture propagation studies, two- and three-dimensional heat extraction solution algorithms have been developed and used to estimate heat extraction and the variations of the reservoir stress with cooling. The numerical models have been developed in a user-friendly environment to create a tool for improving fracture design and investigating single or multiple fracture propagation in rock.

Ahmad Ghassemi

2003-06-30T23:59:59.000Z

125

A synergistic approach to optimizing hydraulic fracturing  

SciTech Connect (OSTI)

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

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

1994-12-31T23:59:59.000Z

126

Safeguards assessment of gamma-ray detection for process monitoring at natural uranium conversion facilities.  

E-Print Network [OSTI]

??Conversion, the process by which natural uranium ore (yellowcake) is puri?ed and converted through a series of chemical processes into uranium hexa?uoride gas (UF6), has… (more)

Dewji, Shaheen Azim

2014-01-01T23:59:59.000Z

127

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

E-Print Network [OSTI]

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

Forbis, Robert E.

2014-01-01T23:59:59.000Z

128

SPATIAL PYRAMID MINING FOR LOGO DETECTION IN NATURAL SCENES University of California Santa Barbara  

E-Print Network [OSTI]

efficiently detect a variety of different lettering or design marks associated with a brand. Features in an image are marked by matching rules to representative examples selected via a weighted cosine similarity measure. Logos are localized in an image via density-based clustering of matched features. Precision vs

California at Santa Barbara, University of

129

Measurement and analysis of fractures in vertical, slant, and horizontal core, with examples from the Mesaverde formation  

SciTech Connect (OSTI)

Optimum analysis of natural fracture characteristics and distributions in reservoirs requires conscientious supervision of coring operations, on-site core processing, careful layout and marketing of the core, and detailed measurement of fracture characteristics. Natural fractures provide information on the in situ permeability system, and coring-induced fractures provide data on the in situ stresses. Fracture data derived from vertical core should include fracture height, type and location of fracture terminations with respect to lithologic heterogeneity, fracture planatary and roughness, and distribution with depth. Fractures in core from either a vertical or a deviated well will yield information on dip, dip azimuth, strike, mineralization, and the orientation of fractures relative to the in situ stresses. Only measurements of fractures in core from a deviated/horizontal well will provide estimates of fracture spacing and porosity. These data can be graphed and cross-plotted to yield semi-quantitative fracture characteristics for reservoir models. Data on the orientations of fractures relative to each other in unoriented core can be nearly as useful as the absolute orientations of fractures. A deviated pilot hole is recommended for fracture assessment prior to a drilling horizontal production well because it significantly enhances the chances of fracture intersection, and therefore of fracture characterization. 35 refs., 20 figs., 2 tabs.

Lorenz, J.C. (Sandia National Labs., Albuquerque, NM (United States)); Hill, R.E. (CER Corp., Las Vegas, NV (United States))

1991-01-01T23:59:59.000Z

130

To mechanics of deformation, flow, and fracture  

E-Print Network [OSTI]

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.

S. L. Arsenjev

2008-09-23T23:59:59.000Z

131

Self-potential observations during hydraulic fracturing  

E-Print Network [OSTI]

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

Moore, J R; Glaser, Steven D

2007-01-01T23:59:59.000Z

132

Self-potential observations during hydraulic fracturing  

E-Print Network [OSTI]

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

Moore, Jeffrey R.; Glaser, Steven D.

2008-01-01T23:59:59.000Z

133

Hydraulic fracture mechanism in unconsolidated formations.  

E-Print Network [OSTI]

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

Hosseini, Seyed Mehran

2012-01-01T23:59:59.000Z

134

SEISMIC INVESTIGATION OF WRENCH FAULTING AND FRACTURING AT RULISON  

E-Print Network [OSTI]

to gas production at Rulison. Fracture zones are associated with fault trends and areas of deformation networks that help determine gas migration and accumulation. This thesis presents the characterization of the complex wrench fault network at Rulison Field, and its linkage to enhanced natural fracture zones. Rulison

135

Confocal {mu}-XRF, {mu}-XAFS, and {mu}-XRD Studies of Sediment from a Nuclear Waste Disposal Natural Analogue Site and Fractured Granite Following a Radiotracer Migration Experiment  

SciTech Connect (OSTI)

Combined {mu}-XRF, {mu}-XAFS, and {mu}-XRD investigations of a uranium-rich tertiary sediment, from a nuclear repository natural analogue site, and a fractured granite bore core section after a column tracer experiment using a Np(V) containing cocktail have been performed. Most {mu}-XRF/{mu}-XAFS measurements are recorded in a confocal geometry to provide added depth information. The U-rich sediment results show uranium to be present as a tetravalent phosphate and that U(IV) is associated with As(V). Arsenic present is either As(V) or As(0). The As(0) forms thin coatings on the surface of pyrite nodules. A hypothesis for the mechanism of uranium immobilization is proposed, where arsenopyrite acted as reductant of ground water dissolved U(VI) leading to precipitation of less soluble U(IV) and thereby forming As(V). Results for the granite sample show the immobilized Np to be tetravalent and associated with facture material.

Denecke, Melissa A.; Brendebach, Boris; Rothe, Joerg; Simon, Rolf [Forschungszentrum Karlsruhe, P.O. Box 3640, D-76021 Karlsruhe (Germany); Janssens, Koen; Nolf, Wout de; Vekemans, Bart [Department of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp (Belgium); Falkenberg, Gerald [Hamburger Synchrotronstrahlungslabor (HASYLAB) at DESY, Notkestr. 85, D-22603 Hamburg (Germany); Somogyi, Andrea [Synchrotron Soleil, F-91192 Gif-sur-Yvette Cedex (France); Noseck, Ulrich [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Theodor-Heuss-Strasse 4, D-38122 Braunschweig (Germany)

2007-02-02T23:59:59.000Z

136

Fracture characterization from attenuation of Stoneley waves across a fracture  

E-Print Network [OSTI]

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

Bakku, Sudhish Kumar

2012-01-01T23:59:59.000Z

137

Laboratory testing of cement grouting of fractures in welded tuff  

SciTech Connect (OSTI)

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.

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

1991-03-01T23:59:59.000Z

138

TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES...  

Open Energy Info (EERE)

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

139

Production-systems analysis for fractured wells  

SciTech Connect (OSTI)

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

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

1988-11-01T23:59:59.000Z

140

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

E-Print Network [OSTI]

Background: The development of horizontal drilling and hydraulic fracturing methods has dramatically increased the potential for the extraction of previously unrecoverable natural gas. Nonetheless, the potential risks and ...

Linkov, Igor

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


141

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

E-Print Network [OSTI]

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

Hervas Ordonez, Rafael Alejandro

2012-01-01T23:59:59.000Z

142

A Rare Isolated Trapezoid Fracture  

E-Print Network [OSTI]

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

Afifi, Negean; Lu, Jenny J

2011-01-01T23:59:59.000Z

143

Radon in Soil Gas Above Bedrock Fracture Sets at the Shepley’s Hill Superfund Site  

SciTech Connect (OSTI)

The Idaho National Laboratory (INL) recently provided technical support for ongoing environmental remediation activities at the Shepley’s Hill remediation site near Devens, MA (Figure 1). The technical support was requested as follow-on work to an initial screening level radiation survey conducted in 2008. The purpose of the original study was to assess the efficacy of the INL-developed Backpack Sodium Iodide System (BaSIS) for detecting elevated areas of natural radioactivity due to the decay of radon-222 gases emanating from the underlying fracture sets. Although the results from the initial study were mixed, the BaSIS radiation surveys did confirm that exposed bedrock outcrops have higher natural radioactivity than the surficial soils, thus a high potential for detecting elevated levels of radon and/or radon daughter products. (INL 2009) The short count times associated with the BaSIS measurements limited the ability of the system to respond to elevated levels of radioactivity from a subsurface source, in this instance radon gas emanating from fracture sets. Thus, it was postulated that a different methodology be employed to directly detect the radon in the soil gases. The CR-39 particle track detectors were investigated through an extensive literature and technology search. The relatively long deployment or “detection” time of several days, as well as the sensitivity of the measurement and robustness of the detectors made the CR-39 technology promising for deployment at the Shepley’s Hill site.

J.R. Giles; T.L. McLing; M.V. Carpenter; C.J. Smith; W. Brandon

2012-12-01T23:59:59.000Z

144

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

E-Print Network [OSTI]

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

Lolon, Elyezer P.

2006-04-12T23:59:59.000Z

145

Integrated Approach to Use Natural Chemical and Isotopic Tracers...  

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

Integrated Approach to Use Natural Chemical and Isotopic Tracers to Estimate Fracture Spacing and Surface Area in EGS Systems Integrated Approach to Use Natural Chemical and...

146

Detect  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct: CrudeOffice ofINLNuclear262AboutDesignerFile SystemDetect

147

Multi-Phase Fracture-Matrix Interactions Under Stress Changes  

SciTech Connect (OSTI)

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

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

2005-12-07T23:59:59.000Z

148

Suspensions in hydraulic fracturing  

SciTech Connect (OSTI)

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

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

1996-12-31T23:59:59.000Z

149

Fracture Detection and Water Sweep Characterization Using Single-well Imaging, Vertical Seismic Profiling and Cross-dipole Methods in Tight and Super-k Zones, Haradh II, Saudi Arabia  

E-Print Network [OSTI]

sustain the targeted oil production rates and they die much sooner than expected when water enters the wells. The study attempted to identify fracture systems and their role in the irregular water sweep. Single-well acoustic migration imaging (SWI...

Aljeshi, Hussain Abdulhadi A.

2012-07-16T23:59:59.000Z

150

FRACTURING FLUID CHARACTERIZATION FACILITY  

SciTech Connect (OSTI)

Hydraulic fracturing technology has been successfully applied for well stimulation of low and high permeability reservoirs for numerous years. Treatment optimization and improved economics have always been the key to the success and it is more so when the reservoirs under consideration are marginal. Fluids are widely used for the stimulation of wells. The Fracturing Fluid Characterization Facility (FFCF) has been established to provide the accurate prediction of the behavior of complex fracturing fluids under downhole conditions. The primary focus of the facility is to provide valuable insight into the various mechanisms that govern the flow of fracturing fluids and slurries through hydraulically created fractures. During the time between September 30, 1992, and March 31, 2000, the research efforts were devoted to the areas of fluid rheology, proppant transport, proppant flowback, dynamic fluid loss, perforation pressure losses, and frictional pressure losses. In this regard, a unique above-the-ground fracture simulator was designed and constructed at the FFCF, labeled ''The High Pressure Simulator'' (HPS). The FFCF is now available to industry for characterizing and understanding the behavior of complex fluid systems. To better reflect and encompass the broad spectrum of the petroleum industry, the FFCF now operates under a new name of ''The Well Construction Technology Center'' (WCTC). This report documents the summary of the activities performed during 1992-2000 at the FFCF.

Subhash Shah

2000-08-01T23:59:59.000Z

151

Characterizing Hydraulic Properties and Ground-Water Chemistry in Fractured-Rock Aquifers: A User's Manual  

E-Print Network [OSTI]

Characterizing Hydraulic Properties and Ground-Water Chemistry in Fractured-Rock Aquifers: A User source for science about the Earth, its natural and living resources, natural hazards., 2007, Characterizing hydraulic properties and ground-water chemistry in fractured-rock aquifers: A user

152

Ultrasound-Confirmed Frontal Bone Fracture  

E-Print Network [OSTI]

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

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

2009-01-01T23:59:59.000Z

153

Self-potential observations during hydraulic fracturing  

E-Print Network [OSTI]

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

Moore, J R; Glaser, Steven D

2007-01-01T23:59:59.000Z

154

Investigation of Created Fracture Geometry through Hydraulic Fracture Treatment Analysis  

E-Print Network [OSTI]

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

Ahmed, Ibraheem 1987-

2012-11-30T23:59:59.000Z

155

The evolution of hydraulic fracturing in the Almond formation  

SciTech Connect (OSTI)

This study draws from a database of over 600 wells to evaluate reservoir, production and treatment characteristics in the low-permeability, naturally-fractured Almond formation. Treatment-induced damage can be significant; damage mechanisms are discussed and ways are shown to mitigate these problems. An effective fracture stimulation design combines proppant scheduling of the late 1970`s with fluid and gel-breaker systems of today.

Cramer, D.D.

1995-12-31T23:59:59.000Z

156

Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture  

E-Print Network [OSTI]

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

157

Reservoir fracture characterizations from seismic scattered waves  

E-Print Network [OSTI]

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

Fang, Xinding

2012-01-01T23:59:59.000Z

158

Fracture Propagation and Permeability Change under Poro-thermoelastic Loads & Silica Reactivity in Enhanced Geothermal Systems  

SciTech Connect (OSTI)

Geothermal energy is recovered by circulating water through heat exchange areas within a hot rock mass. Geothermal reservoir rock masses generally consist of igneous and metamorphic rocks that have low matrix permeability. Therefore, cracks and fractures play a significant role in extraction of geothermal energy by providing the major pathways for fluid flow and heat exchange. Therefore, knowledge of the conditions leading to formation of fractures and fracture networks is of paramount importance. Furthermore, in the absence of natural fractures or adequate connectivity, artificial fractures are created in the reservoir using hydraulic fracturing. Multiple fractures are preferred because of the large size necessary when using only a single fracture. Although the basic idea is rather simple, hydraulic fracturing is a complex process involving interactions of high pressure fluid injections with a stressed hot rock mass, mechanical interaction of induced fractures with existing natural fractures, and the spatial and temporal variations of in-situ stress. As a result, it is necessary to develop tools that can be used to study these interactions as an integral part of a comprehensive approach to geothermal reservoir development, particularly enhanced geothermal systems. In response to this need we have developed advanced poro-thermo-chemo-mechanical fracture models for rock fracture research in support of EGS design. The fracture propagation models are based on a regular displacement discontinuity formulation. The fracture propagation studies include modeling interaction of induced fractures. In addition to the fracture propagation studies, two-dimensional solution algorithms have been developed and used to estimate the impact of pro-thermo-chemical processes on fracture permeability and reservoir pressure. Fracture permeability variation is studied using a coupled thermo-chemical model with quartz reaction kinetics. The model is applied to study quartz precipitation/dissolution, as well as the variation in fracture aperture and pressure. Also, a three-dimensional model of injection/extraction has been developed to consider the impact poro- and thermoelastic stresses on fracture slip and injection pressure. These investigations shed light on the processes involved in the observed phenomenon of injection pressure variation (e.g., in Coso), and allow the assessment of the potential of thermal and chemical stimulation strategies.

Ahmad Ghassemi

2009-10-01T23:59:59.000Z

159

Seismic Fracture Characterization Methods for Enhanced Geothermal...  

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

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

160

Seismic Fracture Characterization Methods for Enhanced Geothermal...  

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

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

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


161

Integrating 3D seismic curvature and curvature gradient attributes for fracture characterization: Methodologies and interpretational implications  

SciTech Connect (OSTI)

In 3D seismic interpretation, curvature is a popular attribute that depicts the geometry of seismic reflectors and has been widely used to detect faults in the subsurface; however, it provides only part of the solutions to subsurface structure analysis. This study extends the curvature algorithm to a new curvature gradient algorithm, and integrates both algorithms for fracture detection using a 3D seismic test data set over Teapot Dome (Wyoming). In fractured reservoirs at Teapot Dome known to be formed by tectonic folding and faulting, curvature helps define the crestal portion of the reservoirs that is associated with strong seismic amplitude and high oil productivity. In contrast, curvature gradient helps better define the regional northwest-trending and the cross-regional northeast-trending lineaments that are associated with weak seismic amplitude and low oil productivity. In concert with previous reports from image logs, cores, and outcrops, the current study based on an integrated seismic curvature and curvature gradient analysis suggests that curvature might help define areas of enhanced potential to form tensile fractures, whereas curvature gradient might help define zones of enhanced potential to develop shear fractures. In certain fractured reservoirs such as at Teapot Dome where faulting and fault-related folding contribute dominantly to the formation and evolution of fractures, curvature and curvature gradient attributes can be potentially applied to differentiate fracture mode, to predict fracture intensity and orientation, to detect fracture volume and connectivity, and to model fracture networks.

Gao, Dengliang

2013-03-01T23:59:59.000Z

162

Fluid Flow Modeling in Fractures  

E-Print Network [OSTI]

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

Sarkar, Sudipta

2004-01-01T23:59:59.000Z

163

FRACTURE STIMULATION IN ENHANCED GEOTHERMAL  

E-Print Network [OSTI]

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

Stanford University

164

Development of a Monitoring Framework for the Detection of Diversion of Intermediate Products in a Generic Natural Uranium Conversion Plant.  

E-Print Network [OSTI]

??The objective of this work is the development of an on-line monitoring and data analysis framework that could detect the diversion of intermediate products such… (more)

Ladd-Lively, Jennifer L.

2013-01-01T23:59:59.000Z

165

Real-time and post-frac' 3-D analysis of hydraulic fracture treatments in geothermal reservoirs  

SciTech Connect (OSTI)

Economic power production from Hot Dry Rock (HDR) requires the establishment of an efficient circulation system between wellbores in reservoir rock with extremely low matrix permeability. Hydraulic fracturing is employed to establish the necessary circulation system. Hydraulic fracturing has also been performed to increase production from hydrothermal reservoirs by enhancing the communication with the reservoir's natural fracture system. Optimal implementation of these hydraulic fracturing applications, as with any engineering application, requires the use of credible physical models and the reconciliation of the physical models with treatment data gathered in the field. Analysis of the collected data has shown that 2-D models and 'conventional' 3-D models of the hydraulic fracturing process apply very poorly to hydraulic fracturing in geothermal reservoirs. Engineering decisions based on these more 'conventional' fracture modeling techniques lead to serious errors in predicting the performance of hydraulic fracture treatments. These errors can lead to inappropriate fracture treatment design as well as grave errors in well placement for hydrothermal reservoirs or HDR reservoirs. This paper outlines the reasons why conventional modeling approaches fall short, and what types of physical models are needed to credibly estimate created hydraulic fracture geometry. The methodology of analyzing actual measured fracture treatment data and matching the observed net fracturing pressure (in realtime as well as after the treatment) is demonstrated at two separate field sites. Results from an extensive Acoustic Emission (AE) fracture diagnostic survey are also presented for the first case study aS an independent measure of the actual created hydraulic fracture geometry.

Wright, C.A.; Tanigawa, J.J.; Hyodo, Masami; Takasugi, Shinji

1994-01-20T23:59:59.000Z

166

Multiple-point statistical prediction on fracture networks at Yucca Mountain  

SciTech Connect (OSTI)

In many underground nuclear waste repository systems, such as at Yucca Mountain, water flow rate and amount of water seepage into the waste emplacement drifts are mainly determined by hydrological properties of fracture network in the surrounding rock mass. Natural fracture network system is not easy to describe, especially with respect to its connectivity which is critically important for simulating the water flow field. In this paper, we introduced a new method for fracture network description and prediction, termed multi-point-statistics (MPS). The process of the MPS method is to record multiple-point statistics concerning the connectivity patterns of a fracture network from a known fracture map, and to reproduce multiple-scale training fracture patterns in a stochastic manner, implicitly and directly. It is applied to fracture data to study flow field behavior at the Yucca Mountain waste repository system. First, the MPS method is used to create a fracture network with an original fracture training image from Yucca Mountain dataset. After we adopt a harmonic and arithmetic average method to upscale the permeability to a coarse grid, THM simulation is carried out to study near-field water flow in the surrounding waste emplacement drifts. Our study shows that connectivity or patterns of fracture networks can be grasped and reconstructed by MPS methods. In theory, it will lead to better prediction of fracture system characteristics and flow behavior. Meanwhile, we can obtain variance from flow field, which gives us a way to quantify model uncertainty even in complicated coupled THM simulations. It indicates that MPS can potentially characterize and reconstruct natural fracture networks in a fractured rock mass with advantages of quantifying connectivity of fracture system and its simulation uncertainty simultaneously.

Liu, X.Y; Zhang, C.Y.; Liu, Q.S.; Birkholzer, J.T.

2009-05-01T23:59:59.000Z

167

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

E-Print Network [OSTI]

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

Nakagawa, S.

2010-01-01T23:59:59.000Z

168

Tilmeter hydraulic fracture imaging enhancement project: Progress repeort  

SciTech Connect (OSTI)

Over half of all oil & gas production wells drilled in the United States depend upon hydraulic fracturing to sustain or enhance production. However, there is no existing technology that allows detailed near-surface imaging of these hydraulically-driven fractures at depths greater than about 5000 feet. To image hydraulic fractures in the 8000`-10,000` depth range, we are currently redesigning tiltmeter tools in order to deploy the instruments deeper to escape the cultural/natural surface noise that often masks the hydrofrac signal. With nearly noise-free data, we should be in a better position to separate the earth-tide signal from the tiltmeter signal and investigate fine-scale hydraulic fracturing processes.

Castillo, D.A. [Lawrence Livermore National Lab., CA (United States); Wright, C.A.; Conant, R.A. [and others

1995-12-31T23:59:59.000Z

169

Fracture Characterization in Enhanced Geothermal Systems by Wellbore...  

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

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

170

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

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

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

171

Radionuclide Transport in Fracture-Granite Interface Zones  

SciTech Connect (OSTI)

In situ radionuclide migration experiments, followed by excavation and sample characterization, were conducted in a water-conducting shear zone at the Grimsel Test Site (GTS) in Switzerland to study diffusion paths of radionuclides in fractured granite. In this work, we employed a micro-scale mapping technique that interfaces laser ablation sampling with inductively coupled plasma-mass spectrometry (LA/ICP-MS) to measure the fine-scale (micron-range) distribution of actinides ({sup 234}U, {sup 235}U, and {sup 237}Np) in the fracture-granite interface zones. Long-lived {sup 234}U, {sup 235}U, and {sup 237}Np were detected in flow channels, as well as in the adjacent rock matrix, using the sensitive, feature-based mapping of the LA/ICP-MS technique. The injected sorbing actinides are mainly located within the advective flowing fractures and the immediately adjacent regions. The water-conducting fracture studied in this work is bounded on one side by mylonite and the other by granitic matrix regions. These actinides did not penetrate into the mylonite side as much as the relatively higher-porosity granite matrix, most likely due to the low porosity, hydraulic conductivity, and diffusivity of the fracture wall (a thickness of about 0.4 mm separates the mylonite region from the fracture) and the mylonite region itself. Overall, the maximum penetration depth detected with this technique for the more diffusive {sup 237}Np over the field experimental time scale of about 60 days was about 10 mm in the granitic matrix, illustrating the importance of matrix diffusion in retarding radionuclide transport from the advective fractures. Laboratory tests and numerical modeling of radionuclide diffusion into granitic matrix was conducted to complement and help interpret the field results. Measured apparent diffusivity of multiple tracers in granite provided consistent predictions for radionuclide transport in the fractured granitic rock.

Hu, Q; Mori, A

2007-09-12T23:59:59.000Z

172

Procedure for estimating fracture energy from fracture surface roughness  

DOE Patents [OSTI]

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

Williford, Ralph E. (Kennewick, WA)

1989-01-01T23:59:59.000Z

173

NREL: News - JISEA News: Study on Methane Emissions from Natural...  

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

rates are unlikely to be representative of typical natural gas system leakage rates. * Hydraulic fracturing is not likely to be a substantial emissions source, relative to...

174

Integrated Approach to Use Natural Chemical and Isotopic Tracers...  

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

Approach to Use Natural Chemical and Isotopic Tracers to Estimate Fracture Spacing and Surface Area in EGS Systems B. Mack Kennedy (Presenter) and H. H. Liu Lawrence Berkeley...

175

Seismic modelling of a fractured carbonate reservoir in Abu Dhabi, United Arab Emirates  

E-Print Network [OSTI]

Seismic modelling of a fractured carbonate reservoir in Abu Dhabi, United Arab Emirates Mohammed Y is required to optimize hydrocarbon production. A rock containing parallel fractures can be seismically to the seismic wavelength. Seismic anisotropy may be detectable from attributes of pre-stack 3-D seismic data

Ali, Mohammed

176

Brittle Fracture Ductile to Brittle transition  

E-Print Network [OSTI]

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

Subramaniam, Anandh

177

Complications in Ankle Fracture Surgery.  

E-Print Network [OSTI]

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

Ovaska, Mikko

2014-01-01T23:59:59.000Z

178

Fracture model for cemented aggregates  

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

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

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

2013-01-01T23:59:59.000Z

179

Seismic anisotropy of fractured rock  

E-Print Network [OSTI]

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

M. Schoenberg, C. M. Sayers

2000-02-18T23:59:59.000Z

180

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

E-Print Network [OSTI]

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

Edinburgh, University of

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


181

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

SciTech Connect (OSTI)

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

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

1997-08-01T23:59:59.000Z

182

Flow dynamics and solute transport in unsaturated rock fractures  

SciTech Connect (OSTI)

Rock fractures play an important role in flow and contaminant transport in fractured aquifers, production of oil from petroleum reservoirs, and steam generation from geothermal reservoirs. In this dissertation, phenomenological aspects of flow in unsaturated fractures were studied in visualization experiments conducted on a transparent replica of a natural, rough-walled rock fracture for inlet conditions of constant pressure and flow rate over a range of angles of inclination. The experiments demonstrated that infiltrating liquid proceeds through unsaturated rock fractures along non-uniform, localized preferential flow paths. Even in the presence of constant boundary conditions, intermittent flow was a persistent flow feature observed, where portions of the flow channel underwent cycles of snapping and reforming. Two modes of intermittent flow were observed, the pulsating blob mode and the rivulet snapping mode. A conceptual model for the rivulet snapping mode was proposed and examined using idealized, variable-aperture fractures. The frequency of intermittent flow events was measured in several experiments and related to the capillary and Bond numbers to characterize this flow behavior.

Su, G. W.

1999-10-01T23:59:59.000Z

183

Interferometric hydrofracture microseism localization using neighboring fracture  

E-Print Network [OSTI]

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. ...

Poliannikov, Oleg V.

2011-05-19T23:59:59.000Z

184

Interferometric hydrofracture microseism localization using neighboring fracture  

E-Print Network [OSTI]

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. ...

Poliannikov, Oleg V.

185

Fracture compliance estimation using borehole tube waves  

E-Print Network [OSTI]

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

Bakku, Sudhish Kumar

186

GEOLOGY AND FRACTURE SYSTEM AT STRIPA  

E-Print Network [OSTI]

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

Olkiewicz, O.

2010-01-01T23:59:59.000Z

187

FRACTURE FAILURE CRITERIA OF SOFC PEN STRUCTURE  

SciTech Connect (OSTI)

Thermal stresses and warpage of the PEN are unavoidable due to the temperature changes from the stress-free sintering temperature to room temperature and mismatch of the coefficients of thermal expansion (CTE) of various layers in the PEN structures of solid oxide fuel cells (SOFC) during the PEN manufacturing process. In the meantime, additional mechanical stresses will also be created by mechanical flattening during the stack assembly process. The porous nature of anode and cathode in the PEN structures determines presence of the initial flaws and crack on the interfaces of anode/electrolyte/cathode and in the interior of the materials. The sintering/assembling induced stresses may cause the fracture failure of PEN structure. Therefore, fracture failure criteria for SOFC PEN structures is developed in order to ensure the structural integrity of the cell and stack of SOFC. In this paper, the fracture criteria based on the relationship between the critical energy release rate and critical curvature and maximum displacement of the warped cells caused by the temperature changes as well as mechanical flattening process is established so that possible failure of SOFC PEN structures may be predicted deterministically by the measurement of the curvature and displacement of the warped cells.

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

2007-04-30T23:59:59.000Z

188

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

E-Print Network [OSTI]

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

Hervas Ordonez, Rafael Alejandro

1994-01-01T23:59:59.000Z

189

A Semi-Analytic Solution for Flow in Finite-Conductivity Vertical Fractures Using Fractal Theory  

E-Print Network [OSTI]

in ultra-tight reservoirs, answers are presently being sought. Fractal theory has been successfully applied to pressure transient testing, albeit with an emphasis on the effects of natural fractures in pressure-rate behavior. In this work, we begin...

Cossio Santizo, Manuel

2012-10-19T23:59:59.000Z

190

Risk assessment of groundwater contamination from hydraulic fracturing fluid spills in Pennsylvania  

E-Print Network [OSTI]

Fast-paced growth in natural gas production in the Marcellus Shale has fueled intense debate over the risk of groundwater contamination from hydraulic fracturing and the shale gas extraction process at large. While several ...

Fletcher, Sarah Marie

2012-01-01T23:59:59.000Z

191

Exploring the physicochemical processes that govern hydraulic fracture through laboratory  

E-Print Network [OSTI]

) containing model boreholes as an analog to hydraulic fracturing with various fracture-driving fluids. The

Belmonte A; Connelly P

192

Seismic Fracture Characterization Methods for Enhanced Geothermal...  

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

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

193

Fracture and Healing of Rock Salt Related to Salt Caverns  

SciTech Connect (OSTI)

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.

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

1999-03-01T23:59:59.000Z

194

Fracture of a biopolymer gel as a viscoplastic disentanglement process  

E-Print Network [OSTI]

We present an extensive experimental study of mode-I, steady, slow crack dynamics in gelatin gels. Taking advantage of the sensitivity of the elastic stiffness to gel composition and history we confirm and extend the model for fracture of physical hydrogels which we proposed in a previous paper (Nature Materials, doi:10.1038/nmat1666 (2006)), which attributes decohesion to the viscoplastic pull-out of the network-constituting chains. So, we propose that, in contrast with chemically cross-linked ones, reversible gels fracture without chain scission.

Tristan Baumberger; Christiane Caroli; David Martina

2006-07-05T23:59:59.000Z

195

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

SciTech Connect (OSTI)

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

Shouchun Deng; Robert Podgorney; Hai Huang

2011-02-01T23:59:59.000Z

196

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

SciTech Connect (OSTI)

The flow parameters of a natural fracture were estimated by modeling in situ pressure pulses. The pulses were generated in two horizontal boreholes spaced 1 m apart vertically and intersecting a near-vertical highly permeable fracture located within a shallow fractured carbonate reservoir. Fracture hydromechanical response was monitored using specialized fiber-optic borehole equipment that could simultaneously measure fluid pressure and fracture displacements. Measurements indicated a significant time lag between the pressure peak at the injection point and the one at the second measuring point, located 1 m away. The pressure pulse dilated and contracted the fracture. Field data were analyzed through hydraulic and coupled hydromechanical simulations using different governing flow laws. In matching the time lag between the pressure peaks at the two measuring points, our hydraulic models indicated that (1) flow was channeled in the fracture, (2) the hydraulic conductivity tensor was highly anisotropic, and (3) the radius of pulse influence was asymmetric, in that the pulse travelled faster vertically than horizontally. Moreover, our parametric study demonstrated that the fluid pressure diffusion through the fracture was quite sensitive to the spacing and orientation of channels, hydraulic aperture, storativity and hydraulic conductivity. Comparison between hydraulic and hydromechanical models showed that the deformation significantly affected fracture permeability and storativity, and consequently, the fluid pressure propagation, suggesting that the simultaneous measurements of pressure and mechanical displacement signals could substantially improve the interpretation of pulse tests during reservoir characterization.

Cappa, F.; Guglielmi, Y.; Rutqvist, J.; Tsang, C.-F.; Thoraval, A.

2008-03-16T23:59:59.000Z

197

Fracture of synthetic diamond M. D. Droty  

E-Print Network [OSTI]

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

Ritchie, Robert

198

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

E-Print Network [OSTI]

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

Rollett, Anthony D.

199

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

E-Print Network [OSTI]

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

Ritchie, Robert

200

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

E-Print Network [OSTI]

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

Ritchie, Robert O.

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


201

Sensitivity analysis of fracture scattering  

E-Print Network [OSTI]

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

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

2010-01-01T23:59:59.000Z

202

Optimization of fracture treatment designs  

E-Print Network [OSTI]

length and fracture conductivity, and well spacing to optimize methane recovery and project economics of coalbed methane reservoirs. Anderson and Philflps g examined several methods of optimizing proppant selection. Proppant selection is very important...

Rueda, Jose Ignacio

2012-06-07T23:59:59.000Z

203

Fracture of aluminum naval structures  

E-Print Network [OSTI]

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

Galanis, Konstantinos, 1970-

2007-01-01T23:59:59.000Z

204

Fracture-Induced Anisotropic Attenuation  

E-Print Network [OSTI]

simplicity. The expanded fracture compliance matrix of each set is. Sf ¼ s11 s12. 0 ..... ?59?. (in MPa), where q = 2,300 kg/m3, e.g., c11 = 23 GPa . We assume a ...

2012-03-23T23:59:59.000Z

205

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

E-Print Network [OSTI]

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

Ogbechie, Joachim Nwabunwanne

2012-02-14T23:59:59.000Z

206

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

E-Print Network [OSTI]

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

Bakku, Sudhish Kumar

2011-01-01T23:59:59.000Z

207

INTERPRETATION OF A HYDRAULIC FRACTURING EXPERIMENT, MONTICELLO, SOUTH CAROLINA  

E-Print Network [OSTI]

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

Narasimhan, T.N.

2014-01-01T23:59:59.000Z

208

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

Open Energy Info (EERE)

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

209

Fracture Evolution Following a Hydraulic Stimulation within an...  

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

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

210

Aging and Fracture of Human Cortical Bone and Tooth Dentin  

E-Print Network [OSTI]

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

Ager III, Joel W.

2008-01-01T23:59:59.000Z

211

Poroelastic modeling of seismic boundary conditions across a fracture  

E-Print Network [OSTI]

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

Schoenberg, M.A.; Nakagawa, S.

2006-01-01T23:59:59.000Z

212

DNAPL invasion into a partially saturated dead-end fracture  

E-Print Network [OSTI]

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

Su, Grace W.; Javandel, Iraj

2008-01-01T23:59:59.000Z

213

Updated fracture incidence rates for the US version of FRAX®  

E-Print Network [OSTI]

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

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

2010-01-01T23:59:59.000Z

214

Transphyseal Fracture of the Distal Humerus in a Neonate  

E-Print Network [OSTI]

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

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

2011-01-01T23:59:59.000Z

215

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

SciTech Connect (OSTI)

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

Takashi Kojima; Yasuhiko Nakagawa; Koji Matsuki; Toshiyuki Hashida

1992-01-01T23:59:59.000Z

216

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

E-Print Network [OSTI]

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

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

2000-01-01T23:59:59.000Z

217

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

SciTech Connect (OSTI)

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

Chen, Z.; Economides, M.J.

1995-12-31T23:59:59.000Z

218

Low natural gas prices may drive up FY 2014-2015 power rates  

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

natural gas prices? Production Much has been written over the past few years about "fracking," the technology of hydraulic fracturing in horizontally drilled wells that has made...

219

Numerical simulation of two-phase flow in discrete fractures using Rayleigh-Ritz finite element method  

E-Print Network [OSTI]

Spontaneous imbibition plays a very important role in the displacement mechanism of non-wetting fluid in naturally fractured reservoirs. We developed a new 2D two-phase finite element numerical model, as available commercial simulators cannot...

Kaul, Sandeep P.

2004-09-30T23:59:59.000Z

220

Optimal fracture treatment design for dry gas wells maximizes well performance in the presence of non-Darcy flow effects  

E-Print Network [OSTI]

This thesis presents a methodology based on Proppant Number approach for optimal fracture treatment design of natural gas wells considering non-Darcy flow effects in the design process. Closure stress is taken into account, by default, because...

Lopez Hernandez, Henry De Jesus

2004-11-15T23:59:59.000Z

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


221

VALIDATION OF MASSIVELY PARALLEL SIMULATIONS OF DYNAMIC FRACTURE AND  

E-Print Network [OSTI]

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

Barr, Al

222

Low temperature fracture evaluation of plasticized sulfur paving mixtures  

E-Print Network [OSTI]

May 1985 Major Subject: Civil Engineering LOW TEMPERATURE FRACTURE EVALUATION OF PLASTICIZED SULFUR PAVING MIXTURES A Thesis by KAMYAR MAHBOUB Approved as to style and content by: Dallas N. Li tie (Chai rman of Committee) Ro e . Lytto Member... modifications to the standard ASTM procedure. These modifications were required due to the nature of plasticized sulfur mixtures and asphalt cement mixtures. The J-integral version of Paris ' law was successfully used to characterize the fatigue...

Mahboub, Kamyar

2012-06-07T23:59:59.000Z

223

Method for directional hydraulic fracturing  

DOE Patents [OSTI]

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

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

1994-01-01T23:59:59.000Z

224

Laboratory investigation of crushed salt consolidation and fracture healing  

SciTech Connect (OSTI)

A laboratory test program was conducted to investigate the consolidation behavior of crushed salt and fracture healing in natural and artificial salt. Crushed salt is proposed for use as backfill in a nuclear waste repository in salt. Artificial block salt is proposed for use in sealing a repository. Four consolidation tests were conducted in a hydrostatic pressure vessel at a maximum pressure of 2500 psi (17.2 MPa) and at room temperature. Three 1-month tests were conducted on salt obtained from the Waste Isolation Pilot Plant and one 2-month test was conducted on salt from Avery Island. Permeability was obtained using argon and either a steady-state or transient method. Initial porosities ranged from 0.26 to 0.36 and initial permeabilities from 2000 to 50,000 md. Final porosities and permeabilities ranged from 0.05 to 0.19 and from <10/sup -5/ md to 110 md, respectively. The lowest final porosity (0.05) and permeability (<10/sup -5/ md) were obtained in a 1-month test in which 2.3% moisture was added to the salt at the beginning of the test. The consolidation rate was much more rapid than in any of the dry salt tests. The fracture healing program included 20 permeability tests conducted on fractured and unfractured samples. The tests were conducted in a Hoek cell at hydrostatic pressures up to 3000 psi (20.6 MPa) with durations up to 8 days. For the natural rock salt tested, permeability was strongly dependent on confining pressure and time. The effect of confining pressure was much weaker in the artificial salt. In most cases the combined effects of time and pressure were to reduce the permeability of fractured samples to the same order of magnitude (or less) as the permeability measured prior to fracturing.

Not Available

1987-01-01T23:59:59.000Z

225

Nonplanar fracture propagation from a horizontal wellbore: Experimental study  

SciTech Connect (OSTI)

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

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

1996-08-01T23:59:59.000Z

226

Harmonic experiments to model fracture induced anisotropy KAUST ...  

E-Print Network [OSTI]

May 9, 2012 ... hydrocarbon and geothermal reservoirs are mainly composed of fractured rocks. Harmonic experiments to model fracture induced anisotropy ...

santos,,,

227

Tracer Methods for Characterizing Fracture Stimulation in Engineered...  

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

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

228

Modeling of Acid Fracturing in Carbonate Reservoirs  

E-Print Network [OSTI]

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

Al Jawad, Murtada s

2014-06-05T23:59:59.000Z

229

Self-potential observations during hydraulic fracturing  

E-Print Network [OSTI]

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

Moore, Jeffrey R.; Glaser, Steven D.

2008-01-01T23:59:59.000Z

230

Acoustic Character Of Hydraulic Fractures In Granite  

E-Print Network [OSTI]

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

Paillet, Frederick I.

1983-01-01T23:59:59.000Z

231

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

E-Print Network [OSTI]

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

Boyer, Edmond

232

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

E-Print Network [OSTI]

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

Grujicic, Mica

233

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

E-Print Network [OSTI]

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

Ritchie, Robert

234

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

E-Print Network [OSTI]

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

Espinosa, Horacio D.

235

Discrete fracture modeling for fractured reservoirs using Voronoi grid blocks  

E-Print Network [OSTI]

or pseudofracture groups modeled in their own grid blocks. Discrete Fracture Modeling (DFN) is still a relatively new field, and most research on it up to this point has been done with Delaunay tessellations. This research investigates an alternative approach using...

Gross, Matthew Edward

2007-09-17T23:59:59.000Z

236

Wave Propagation in Fractured Poroelastic Media  

E-Print Network [OSTI]

Seismic wave propagation through fractures and cracks is an important subject in exploration and production geophysics, earthquake seismology and mining.

237

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

SciTech Connect (OSTI)

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

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

2006-05-15T23:59:59.000Z

238

Acoustic-emission monitoring during hydraulic fracturing  

SciTech Connect (OSTI)

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

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

1992-06-01T23:59:59.000Z

239

Hydraulic Fracturing in Michigan Integrated Assessment  

E-Print Network [OSTI]

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

Kamat, Vineet R.

240

Regulation of Hydraulic Fracturing in California  

E-Print Network [OSTI]

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

Kammen, Daniel M.

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


241

Challenges in Continuum Modelling of Intergranular Fracture  

E-Print Network [OSTI]

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

Sethna, James P.

242

FRACTURE IN DISORDERED BRITTLE MEDIA A Dissertation  

E-Print Network [OSTI]

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

Sethna, James P.

243

FRACTURE TOUGHNESS OF WOOD AND WOOD COMPOSITES  

E-Print Network [OSTI]

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

Nairn, John A.

244

Models for MetaVCeramic Interface Fracture  

E-Print Network [OSTI]

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

Suo, Zhigang

245

Interferometric hydrofracture microseism localization using neighboring fracture  

E-Print Network [OSTI]

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

Malcolm, Alison

246

Hydraulic Fracture: multiscale processes and moving  

E-Print Network [OSTI]

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

Peirce, Anthony

247

Hydraulic Fracture: multiscale processes and moving  

E-Print Network [OSTI]

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

Peirce, Anthony

248

Introduction That fracture is governed by processes  

E-Print Network [OSTI]

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

Beltz, Glenn E.

249

LA-13194-MS Fracture Characterization of the  

E-Print Network [OSTI]

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

250

Capillary fracture of soft gels  

E-Print Network [OSTI]

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

Bostwick, Joshua B

2013-01-01T23:59:59.000Z

251

Relative Permeability of Fractured Rock  

E-Print Network [OSTI]

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

Stanford University

252

Mechanical and transport properties of rocks at high temperatures and pressures. Task II: fracture permeability of crystalline rocks as a function of temperature, pressure, and hydrothermal alteration  

SciTech Connect (OSTI)

The primary objective is to measure and understand the variation of the fracture permeability of quartzite subjected to hydrothermal conditions. Pore fluids will consist of distilled water and aqueous Na/sub 2/CO/sub 3/ solutions at temperatures to 250/sup 0/C, fluid pressures to 20 MPa and effective normal stresses to 70 MPa. Fluid flow rates will be controllable to rates at least as small as 0.2 ml/day (approx. 4 fracture volumes). Experiments are designed to assess what role, if any, pressure solution may play at time scales of those of the experiments (less than or equal to 2 weeks). Secondary objectives are: (1) continue simulated fracture studies, incorporating inelastic deformation into model and characterize the nature of inelastic deformation occurring on loaded tensile fractures in quartzite; (2) continue dissolution experiment, with emphasis on dissolution modification of tensile fracture surfaces on quartzite; and (3) study natural fractures in a quartzite exhibiting hydrothermal dissolution features.

Not Available

1981-01-01T23:59:59.000Z

253

Geomechanical Simulation of Fluid-Driven Fractures  

SciTech Connect (OSTI)

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

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

2012-11-30T23:59:59.000Z

254

CONSTRAINT EFFECT IN FRACTURE WHAT IS IT  

SciTech Connect (OSTI)

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

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

2008-10-29T23:59:59.000Z

255

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

SciTech Connect (OSTI)

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

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

1992-04-01T23:59:59.000Z

256

RESEARCH PROGRAM ON FRACTURED PETROLEUM RESERVOIRS  

SciTech Connect (OSTI)

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.

Abbas Firoozabadi

2002-04-12T23:59:59.000Z

257

Interaction between Injection Points during Hydraulic Fracturing  

E-Print Network [OSTI]

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

Hals, Kjetil M D

2012-01-01T23:59:59.000Z

258

Experience proves forced fracture closure works  

SciTech Connect (OSTI)

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

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

1996-01-01T23:59:59.000Z

259

Stent Fracture and Reocclusion After Placement of a Single Self-Expanding Stent in the Common Iliac Artery and Endovascular Treatment  

SciTech Connect (OSTI)

We present a case of fracture of a single self-expanding stent placed in the common iliac artery (CIA). An 80-year-old woman underwent placement of a self-expanding stent for CIA occlusion. Stent fracture and reocclusion were detected after 18 months. Successful revascularization was achieved using a stent-in-stent maneuver. The possibility of stent fracture with reocclusion should be considered following treatment with a single self-expanding stent for CIA occlusion.

Higashiura, Wataru, E-mail: wataruhigashiura@hotmail.com; Sakaguchi, Shoji; Morimoto, Kengo; Kichikawa, Kimihiko [Nara Medical University, Department of Radiology (Japan)

2008-09-15T23:59:59.000Z

260

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

SciTech Connect (OSTI)

Schoenberg's Linear-slip Interface (LSI) model for single, compliant, viscoelastic fractures has been extended to poroelastic fractures for predicting seismic wave scattering. However, this extended model results in no impact of the in-plane fracture permeability on the scattering. Recently, we proposed a variant of the LSI model considering the heterogeneity in the in-plane fracture properties. This modified model considers wave-induced, fracture-parallel fluid flow induced by passing seismic waves. The research discussed in this paper applies this new LSI model to heterogeneous fractures to examine when and how the permeability of a fracture is reflected in the scattering of seismic waves. From numerical simulations, we conclude that the heterogeneity in the fracture properties is essential for the scattering of seismic waves to be sensitive to the permeability of a fracture.

Nakagawa, S.; Myer, L.R.

2009-06-15T23:59:59.000Z

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


261

Acid Fracture and Fracture Conductivity Study of Field Rock Samples  

E-Print Network [OSTI]

(Black and Hower 1965). Clays consist of negatively charged aluminosilicate layers kept together by cations. The most characteristic property is their ability to adsorb water between the layers, resulting in strong repulsive forces and clay expansion... chemicals used in water fracturing such as friction reducers, fluid-loss additives, and surfactants (Black and Hower 1965). The samples used in this study had significant clay-like content. To prevent swelling, a 2% KCl solution was used throughout...

Underwood, Jarrod

2013-11-15T23:59:59.000Z

262

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

E-Print Network [OSTI]

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

Wang, J.S.Y.

2013-01-01T23:59:59.000Z

263

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]

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...

Pieve La Rosa, Andres Eduardo

2011-08-08T23:59:59.000Z

264

Predicting fracture in micron-scale polycrystalline silicon MEMS structures.  

SciTech Connect (OSTI)

Designing reliable MEMS structures presents numerous challenges. Polycrystalline silicon fractures in a brittle manner with considerable variability in measured strength. Furthermore, it is not clear how to use a measured tensile strength distribution to predict the strength of a complex MEMS structure. To address such issues, two recently developed high throughput MEMS tensile test techniques have been used to measure strength distribution tails. The measured tensile strength distributions enable the definition of a threshold strength as well as an inferred maximum flaw size. The nature of strength-controlling flaws has been identified and sources of the observed variation in strength investigated. A double edge-notched specimen geometry was also tested to study the effect of a severe, micron-scale stress concentration on the measured strength distribution. Strength-based, Weibull-based, and fracture mechanics-based failure analyses were performed and compared with the experimental results.

Hazra, Siddharth S. (Carnegie Mellon University, Pittsburgh, PA); de Boer, Maarten Pieter (Carnegie Mellon University, Pittsburgh, PA); Boyce, Brad Lee; Ohlhausen, James Anthony; Foulk, James W., III; Reedy, Earl David, Jr.

2010-09-01T23:59:59.000Z

265

Drill-back studies examine fractured, heated rock  

SciTech Connect (OSTI)

To investigate the effects of heating on the mineralogical, geochemical, and mechanical properties of rock by high-level radioactive waste, cores are being examined from holes penetrating locations where electric heaters simulated the presence of a waste canister, and from holes penetration natural hydrothermal systems. Results to date indicate the localized mobility and deposition of uranium in an open fracture in heated granitic rock, the mobility of U in a breccia zone in an active hydrothermal system in tuff, and the presence of U in relatively high concentration in fracture-lining material in tuff. Mechanical -- property studies indicate that differences in compressional- and shear-wave parameters between heated and less heated rock can be attributed to differences in the density of microcracks. Emphasis has shifted from initial studies of granitic rock at Stripa, Sweden to current investigations of welded tuff at the Nevada Test Site. 7 refs., 8 figs.

Wollenberg, H.A.; Flexser, S.; Myer, L.R.

1990-01-01T23:59:59.000Z

266

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

E-Print Network [OSTI]

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

Nelson, J.T.

2009-01-01T23:59:59.000Z

267

Using seismic tomography to characterize fracture systems induced by hydraulic fracturing  

SciTech Connect (OSTI)

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

Fehler, M.; Rutledge, J.

1995-01-01T23:59:59.000Z

268

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

SciTech Connect (OSTI)

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.

Riha, B; Warren Hyde, W; Richard Hall (NOEMAIL), R

2008-03-12T23:59:59.000Z

269

Apparatus and method for monitoring underground fracturing  

DOE Patents [OSTI]

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

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

1999-08-10T23:59:59.000Z

270

Apparatus and method for monitoring underground fracturing  

DOE Patents [OSTI]

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

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

1999-08-10T23:59:59.000Z

271

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

SciTech Connect (OSTI)

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

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

2008-07-01T23:59:59.000Z

272

Characterization of EGS Fracture Network Lifecycles  

SciTech Connect (OSTI)

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

Gillian R. Foulger

2008-03-31T23:59:59.000Z

273

A Political Ecology of Hydraulic Fracturing for Natural Gas in  

E-Print Network [OSTI]

environments, both in terms of perception and in terms of physical space. (Robbins 2004) #12;Outline ! Background of Marcellus Shale Gas Play ! Current Events: The Case of PA ! Geography of Fracking in Study Corbett #12;PA's Marcellus Shale Country is constructed as a Neoliberal Environment · Residents

Scott, Christopher

274

Continuous Model Updating and Forecasting for a Naturally Fractured Reservoir  

E-Print Network [OSTI]

result in suboptimal decisions and huge disappointments (see Sec. 1.2.2) Reservoir simulation literature indicates that an acceptable level of matching historical reservoir performance is required to establish reliable forecasts. However, this does... and field production. Such capabilities enable continuous and automatic fine-tuning of production controls to optimize project economics and/or some well or reservoir performance stated objective. Remotely activated sub-surface valves on ?smart wells...

Almohammadi, Hisham

2013-07-26T23:59:59.000Z

275

The imbibition process of waterflooding in naturally fractured reservoirs  

E-Print Network [OSTI]

David S. Schechter (Chair of Committee) (Member) Brian J. Willis Hans C. Juvkam-Wold (Member... me to complete this work. Thank you to Drs. David Schechter and Brian Willis for serving as members of my graduate advisory committee. I would also like to thank Mirko Hernandez, Fernando Changanaqui, Kimberly Wolf, Carlos Hinostroza, Miguel De...

Huapaya Lopez, Christian A.

2005-02-17T23:59:59.000Z

276

Modeling wettability alteration in naturally fractured carbonate reservoirs.  

E-Print Network [OSTI]

??The demand for energy and new oil reservoirs around the world has increased rapidly while oil recovery from depleted reservoirs has become more difficult. Oil… (more)

Goudarzi, Ali

2012-01-01T23:59:59.000Z

277

Wave Propagation in Fractured Poroelastic Media  

E-Print Network [OSTI]

Wave Propagation in Fractured. Poroelastic Media. WCCM, Barcelona, Spain, July 2014. Juan E. Santos,. 1. 1. Instituto del Gas y del Petr´oleo (IGPUBA), UBA,

2014-06-22T23:59:59.000Z

278

Fracture permeability and seismic wave scattering ŒPoroelastic ...  

E-Print Network [OSTI]

Jun 18, 2010 ... The new model contains fracture permeability in the plan-parallel direction. ... Division of Chemical Sciences of the U.S. Department of Energy ...

Seiji Nakagawa

2010-02-03T23:59:59.000Z

279

Method of fracturing a geological formation  

DOE Patents [OSTI]

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

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

1990-01-01T23:59:59.000Z

280

Fracture characteristics and their relationships to producing...  

Open Energy Info (EERE)

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

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


281

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

Office of Scientific and Technical Information (OSTI)

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

282

Structural Settings Of Hydrothermal Outflow- Fracture Permeability...  

Open Energy Info (EERE)

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

283

Seismic Fracture Characterization Methods for Enhanced Geothermal...  

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

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

284

Microseismic Tracer Particles for Hydraulic Fracturing  

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

can be discriminateddetected that correspond to only the portion of the hydraulic fracture that contains the proppant material and can be expected to be conductive to the flow...

285

Regional Analysis And Characterization Of Fractured Aquifers...  

Open Energy Info (EERE)

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

286

Microearthquake Technology for EGS Fracture Characterization...  

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

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

287

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

288

Coordinated studies in support of hydraulic fracturing of coalbed methane. Annual report, January 1993-April 1994  

SciTech Connect (OSTI)

The production of natural gas from coal typically requires stimulation in the form of hydraulic fracturing and, more recently, cavity completions. The results of hydraulic fracturing treatments have ranged from extremely successful to less than satisfactory. The purpose of this work is to characterize common and potential fracturing fluids in terms of coal-fluid interactions to identify reasons for less than satisfactory performance and to ultimately devise alternative fluids and treatment procedures to optimize production following hydraulic fracturing. The laboratory data reported herein has proven helpful in designing improved hydraulic fracturing treatments and remedial treatments in the Black Warrior Basin. Acid inhibitors, scale inhibitors, additives to improve coal relative permeability to gas, and non-damaging polymer systems for hydraulic fracturing have been screened in coal damage tests. The optimum conditions for creating field-like foams in the laboratory have been explored. Tests have been run to identify minimum polymer and surfactant concentrations for applications of foam in coal. The roll of 100 mesh sand in controlling leakoff and impairing conductivity in coal has been investigated. The leakoff and proppant transport of fluids with breaker has been investigated and recommendations have been made for breaker application to minimize damage potential in coal. A data base called COAL`S has been created in Paradox (trademark) for Windows to catalogue coalbed methane activities in the Black Warrior and San Juan Basins.

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

1994-08-01T23:59:59.000Z

289

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

SciTech Connect (OSTI)

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

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

1991-08-01T23:59:59.000Z

290

Laboratory-scale fracture conductivity created by acid etching  

E-Print Network [OSTI]

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

Pournik, Maysam

2009-05-15T23:59:59.000Z

291

FINITE FRACTURE MECHANICS OF MATRIX MICROCRACKING IN COMPOSITES  

E-Print Network [OSTI]

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

Nairn, John A.

292

Seismic characterization of fractured reservoirs using 3D double beams  

E-Print Network [OSTI]

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

Zheng, Yingcai

2012-01-01T23:59:59.000Z

293

Ductile fracture modeling : theory, experimental investigation and numerical verification  

E-Print Network [OSTI]

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 ...

Xue, Liang, 1973-

2007-01-01T23:59:59.000Z

294

Numerical simulation of hydraulic fracturing  

E-Print Network [OSTI]

of Eq. 21, in its present form, is unstable. The change in fracture cell volume over the time step, BV/At, must be known to calculate pressures at the new time level. Since the value of the AV/At term is dependent on the pressure being solved for... is unconditionally stable and, therefore, guarantees a solution for any time step size~s. To implicitly expand the AV/At term, the pressure change component Ap /At must be extracted so that pex(t+At) can be placed ex on the left hand side of Eq. 21. The AV...

Warner, Joseph Barnes

1987-01-01T23:59:59.000Z

295

Evaluation of fracture treatment type on the recovery of gas from the cotton valley formation  

E-Print Network [OSTI]

Every tight gas well needs to be stimulated with a hydraulic fracture treatment to produce natural gas at economic flow rates and recover a volume of gas that provides an acceptable return on investment. Over the past few decades, many different...

Yalavarthi, Ramakrishna

2009-05-15T23:59:59.000Z

296

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

E-Print Network [OSTI]

program. The main contributions of this work are: An optimal fracture design methodology called unified fracture design (UFD) is presented and damage effects are considered in the optimal design calculation. As a by-product of UFD, a fracture evaluation...

Wang, Wenxin

2006-04-12T23:59:59.000Z

297

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

E-Print Network [OSTI]

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

Rutqvist, J.

2011-01-01T23:59:59.000Z

298

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

E-Print Network [OSTI]

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

Cotte, F.P.

2012-01-01T23:59:59.000Z

299

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

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

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

300

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

SciTech Connect (OSTI)

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

Petti, Jason P.; Kalan, Robert J.

2011-12-01T23:59:59.000Z

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


301

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

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

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

302

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...

303

Fracture Characterization in Enhanced Geothermal Systems by Wellbore...  

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

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

304

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

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

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

305

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

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

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

306

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...

307

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

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

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

308

Fracture Characterization in Enhanced Geothermal Systems by Wellbore...  

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

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

309

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

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

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

310

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

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

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

311

Fracture Evolution Following a Hydraulic Stimulation within an...  

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

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

312

Poroelastic modeling of seismic boundary conditions across a fracture  

E-Print Network [OSTI]

Permeability of a fracture can affect how the fracture interacts with seismic waves. ... characteristic parameters that control the seismic response of single ...

2007-07-20T23:59:59.000Z

313

Finite Conductivity Fractures in Elliptical Coordinates  

E-Print Network [OSTI]

TO THE DEPARTMENT OF PETROLEUM ENGINEERING AND THE COMMITTEE ON GRADUATE STUDIES OF STANFORD UNIVERSITY IN PARTIAL well performance. Indeed, a large number of wells, which could not otherwise be operated economically, it is important that means be available to evaluate fracture effectiveness. The most widely used tool in fracture

Stanford University

314

Fracture Conductivity of the Eagle Ford Shale  

E-Print Network [OSTI]

such as the Eagle Ford Shale. This work investigates the fracture conductivities of seven Eagle Ford Shale samples collected from an outcrop of facies B. Rough fractures were induced in the samples and laboratory experiments that closely followed the API RP-61...

Guzek, James J

2014-07-25T23:59:59.000Z

315

Accounting for Remaining Injected Fracturing Fluid  

E-Print Network [OSTI]

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

Zhang, Yannan

2013-12-06T23:59:59.000Z

316

Fracture mechanics of cellular glass  

SciTech Connect (OSTI)

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

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

1981-02-01T23:59:59.000Z

317

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

SciTech Connect (OSTI)

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

Detwiler, Russell

2014-04-30T23:59:59.000Z

318

FRACTURE DETECTION IN CRYSTALLINE ROCK USING ULTRASONIC SHEAR WAVES  

E-Print Network [OSTI]

the piezoelectric source plate and the rock surface. With aThe S^j sources were bonded to the rock surface with a fast-^ source plate was epoxied in position on the rock specimen.

Waters, K.H.

2011-01-01T23:59:59.000Z

319

FRACTURE DETECTION IN CRYSTALLINE ROCK USING ULTRASONIC SHEAR WAVES  

E-Print Network [OSTI]

Storage of Nuclear Waste in Granite bv P. A. Witherspoon, P.Permeability Test of the Granite in the Stripa Mine andProperties of the Stripa Granite by Graham Swan. (LBL-7074,

Waters, K.H.

2011-01-01T23:59:59.000Z

320

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:YearRound-UpHeat Pump Models |Conduct, Parent Company AgreesDesiree Pipkins AboutCourseGeothermal

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


321

Self-potential observations during hydraulic fracturing  

SciTech Connect (OSTI)

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

Moore, Jeffrey R.; Glaser, Steven D.

2007-09-13T23:59:59.000Z

322

Stress- and Chemistry-Mediated Permeability Enhancement/Degradation in Stimulated Critically-Stressed Fractures  

SciTech Connect (OSTI)

This work has investigated the interactions between stress and chemistry in controlling the evolution of permeability in stimulated fractured reservoirs through an integrated program of experimentation and modeling. Flow-through experiments on natural and artificial fractures in Coso diorite have examined the evolution of permeability under paths of mean and deviatoric stresses, including the role of dissolution and precipitation. Models accommodating these behaviors have examined the importance of incorporating the complex couplings between stress and chemistry in examining the evolution of permeability in EGS reservoirs. This document reports the findings of experiment [1,2] and analysis [3,4], in four sequential chapters.

Derek Elsworth; Abraham S. Grader; Chris Marone; Phillip Halleck; Peter Rose; Igor Faoro; Joshua Taron; André Niemeijer; Hideaki Yasuhara

2009-03-30T23:59:59.000Z

323

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

SciTech Connect (OSTI)

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.

Poston, S.W.

1991-12-31T23:59:59.000Z

324

Fracture-resistant lanthanide scintillators  

DOE Patents [OSTI]

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

Doty, F. Patrick (Livermore, CA)

2011-01-04T23:59:59.000Z

325

High Energy Gas Fracturing Test  

SciTech Connect (OSTI)

The Rocky Mountain Oilfield Testing Center (RMOTC) has recently completed two tests of a high-energy gas fracturing system being developed by Western Technologies of Crossville, Tennessee. The tests involved the use of two active wells located at the Naval Petroleum Reserve No. 3 (NPR-3), thirty-five miles north of Casper, Wyoming (See Figure 1). During the testing process the delivery and operational system was enhanced by RMOTC, Western Technologies, and commercial wireline subcontractors. RMOTC has assisted an industrial client in developing their technology for high energy gas fracturing to a commercial level. The modifications and improvements implemented during the technology testing process are instrumental in all field testing efforts at RMOTC. The importance of well selection can also be critical in demonstrating the success of the technology. To date, significant increases in well productivity have been clearly proven in well 63-TPX-10. Gross fluid production was initially raised by a factor of three. Final production rates increased by a factor of six with the use of a larger submersible pump. Well productivity (bbls of fluid per foot of drawdown) increased by a factor of 15 to 20. The above results assume that no mechanical damage has occurred to the casing or cast iron bridge plug which could allow well production from the Tensleep ''B'' sand. In the case of well 61-A-3, a six-fold increase in total fluid production was seen. Unfortunately, the increase is clouded by the water injection into the well that was necessary to have a positive fluid head on the propellant tool. No significant increase in oil production was seen. The tools which were retrieved from both 63-TPX-10 and 61-A-3 indicated a large amount of energy, similar to high gram perforating, had been expended downhole upon the formation face.

Schulte, R.

2001-02-27T23:59:59.000Z

326

Testing sand used in hydraulic fracturing operations  

SciTech Connect (OSTI)

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

Not Available

1983-03-01T23:59:59.000Z

327

Envelope of Fracture Density Dragana Todorovic-Marinic*  

E-Print Network [OSTI]

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

Santos, Juan

328

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.

329

Coupling schemes for modeling hydraulic fracture propagation using the XFEM  

E-Print Network [OSTI]

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

Peirce, Anthony

330

Calibration of hydraulic and tracer tests in fractured media  

E-Print Network [OSTI]

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

Politècnica de Catalunya, Universitat

331

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

E-Print Network [OSTI]

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

Liu, Yuwei

2013-01-01T23:59:59.000Z

332

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

E-Print Network [OSTI]

make necessary continuous efforts to reduce costs and improve efficiency in all aspects of drilling, completion and production techniques. Many of the recent improvements have been in well completions and hydraulic fracturing. Thus, the main goal of a...

Correa Castro, Juan

2011-08-08T23:59:59.000Z

333

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

SciTech Connect (OSTI)

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

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

1996-08-01T23:59:59.000Z

334

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

335

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

E-Print Network [OSTI]

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

Collins, Gary S.

336

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

E-Print Network [OSTI]

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

Ritchie, Robert

337

Percutaneous Vertebroplasty for Osteoporotic Compression Fracture: Multivariate Study of Predictors of New Vertebral Body Fracture  

SciTech Connect (OSTI)

Purpose. To investigate the risk factors and relative risk of new compression fractures following vertebroplasty. Methods. Initially, we enrolled 104 consecutive patients with vertebral compression fractures caused by osteoporosis. A total of 83 of the 104 patients visited our hospital for follow-up examinations for more than 4 weeks after vertebroplasty. Logistic regression analysis of the data obtained from these 83 patients was used to determine relative risks of recurrent compression fractures, using 13 different factors. Results. We identified 59 new fractures in 30 of the 83 patients: 41 new fractures in vertebrae adjacent to treated vertebrae; and 18 new fractures in vertebrae not adjacent to treated vertebrae. New fractures occurred in vertebrae adjacent to treated vertebrae significantly more frequently than in vertebrae not adjacent to treated vertebrae. Only cement leakage into the disk was a significant predictor of new vertebral body fracture after vertebroplasty (odds ratio = 4.633). None of the following covariates were associated with increased risk of new fracture: age, gender, bone mineral density, the number of vertebroplasty procedures, the number of vertebrae treated per procedure, the cumulative number of vertebrae treated, the presence of a single untreated vertebra between treated vertebrae, the presence of multiple untreated vertebrae between treated vertebrae, the amount of bone cement injected per procedure, the cumulative amount of bone cement injected, cement leakage into the soft tissue around the vertebra, and cement leakage into the vein.

Komemushi, Atsushi, E-mail: kome64@yo.rim.or.jp; Tanigawa, Noboru; Kariya, Shuji; Kojima, Hiroyuki; Shomura, Yuzo [Kansai Medical University, Department of Radiology (Japan); Komemushi, Sadao [Kinki University, Schoool of Agriculture (Japan); Sawada, Satoshi [Kansai Medical University, Department of Radiology (Japan)

2006-08-15T23:59:59.000Z

338

Hydraulic fracturing: A proven N.O.R.M. disposal method  

SciTech Connect (OSTI)

Since the discovery that many drill cuttings, scales, sludges, and platings contain elevated amounts of naturally occurring radioactive material (NORM), many companies and regulating authorities have discussed the merits of various disposal methods. This paper covers a process that disposes of NORM and provides isolation of the material from the environment. Disposal of NORM slurry through fracturing an existing depleted sandstone requires careful analysis to optimize a safe and effective design. A radioactivity assay was performed on the NORM before and after slurrification to determine activity concentrations. Tests were conducted on the NORM to proved parameters for the fracture design. The process consists of slurrying the material and keeping the particles suspended in solution until time for well injection. Well injection takes the form of hydraulic fracturing with the material into a deplete zone in the reservoir. Fracturing with the NORM was preceded with a Mini-Frac as a safety precaution to confirm downhole parameters. In conclusion, the philosophy of the process is to take the NORM generated through the exploration and production of oil and gas and place it back into the reservoir from which it came through hydraulic fracturing. This technique is one that helps protect the environment from the possible hazards associated with mismanaged NORM.

Young, S.C. [Halliburton Energy Services, New Orleans, LA (United States); Chambers, D.G. [Halliburton Energy Services, Lafayette, LA (United States); Woods, S.E.; Abernathy, S.E. [Halliburton Energy Services, Duncan, OK (United States)

1995-10-01T23:59:59.000Z

339

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

SciTech Connect (OSTI)

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

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

2013-11-19T23:59:59.000Z

340

Hydraulic fracturing accelerates coalbed methane recovery  

SciTech Connect (OSTI)

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

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

1990-11-01T23:59:59.000Z

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


341

Multiphase flow in fractured porous media  

SciTech Connect (OSTI)

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

Firoozabadi, A.

1995-02-01T23:59:59.000Z

342

Hydraulic fractur ing--also called hy  

E-Print Network [OSTI]

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

Goodman, Robert M.

343

Dynamic Fracture Toughness of Polymer Composites  

E-Print Network [OSTI]

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

Harmeet Kaur

2012-02-14T23:59:59.000Z

344

Anomalous transport through porous and fractured media  

E-Print Network [OSTI]

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

Kang, Peter Kyungchul

2014-01-01T23:59:59.000Z

345

Geomechanical review of hydraulic fracturing technology  

E-Print Network [OSTI]

Hydraulic fracturing as a method for recovering unconventional shale gas has been around for several decades. Significant research and improvement in field methods have been documented in literature on the subject. The ...

Arop, Julius Bankong

2013-01-01T23:59:59.000Z

346

Universal asymptotic umbrella for hydraulic fracture modeling  

E-Print Network [OSTI]

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

Linkov, Aleksandr M

2014-01-01T23:59:59.000Z

347

Gas condensate damage in hydraulically fractured wells  

E-Print Network [OSTI]

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

Adeyeye, Adedeji Ayoola

2004-09-30T23:59:59.000Z

348

Fracture of Thermosetting Polymers: Experiments and Modeling  

E-Print Network [OSTI]

for the designation as UNDERGRADUATE RESEARCH SCHOLAR A Senior Scholars Thesis by BRAD EVIN BURGESS FRACTURE OF THERMOSETTING POLYMERS: EXPERIMENTS AND MODELING Approved by: Research Advisor: Amine Benzerga Associate Dean for Undergraduate... Scholars Thesis by BRAD EVIN BURGESS iii ABSTRACT Fracture of Thermosetting Polymers: Experiments and Modeling. (April 2009) Brad Evin Burgess Department of Aerospace Engineering Texas A&M University Research Advisor: Dr. Amine Benzerga...

Benzerga, Amine; Burgess, Brad

2011-08-04T23:59:59.000Z

349

FRACTURE TOUGHNESS VARIABILITY IN F82H  

SciTech Connect (OSTI)

The fracture toughness database for F82H displays some anomalous behavior. Metallographic examination reveals banding in the center of 25 mm thick F82H plate, which is more evident in transverse section. The banding is shown to arise because some grains are etched on a very fine scale whereas the remainder is etched more strongly and better delineates the martensite lath structure. However, the banding found does not provide explanation for the anomalous fracture toughness behavior.

Gelles, David S.; Sokolov, M.

2003-09-03T23:59:59.000Z

350

TRITIUM EFFECTS ON WELDMENT FRACTURE TOUGHNESS  

SciTech Connect (OSTI)

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

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

2006-07-17T23:59:59.000Z

351

Geochemical evidence for possible natural migration of Marcellus Formation brine to  

E-Print Network [OSTI]

as the potential for contamination from toxic substances in hydraulic fracturing fluid and/or pro- duced brinesGeochemical evidence for possible natural migration of Marcellus Formation brine to shallow of stray gas, metal-rich formation brines, and hydrau- lic fracturing and/or flowback fluids to drinking

352

Estimation of Fracture Porosity in an Unsaturated Fractured Welded Tuff Using Gas Tracer Testing  

SciTech Connect (OSTI)

Kinematic fracture porosity is an important hydrologic transport parameter for predicting the potential of rapid contaminant migration through fractured rock. The transport velocity of a solute moving within a fracture network is inversely related to the fracture porosity. Since fracture porosity is often one or two orders of magnitude smaller than matrix porosity, and fracture permeability is often orders of magnitude greater than matrix permeability, solutes may travel significantly faster in the fracture network than in the surrounding matrix. This dissertation introduces a new methodology for conducting gas tracer tests using a field portable mass spectrometer along with analytical tools for estimating fracture porosity using the measured tracer concentration breakthrough curves. Field experiments were conducted at Yucca Mountain, Nevada, consisting of air-permeability transient testing and gas-tracer-transport tests. The experiments were conducted from boreholes drilled within an underground tunnel as part of an investigation of rock mass hydrological behavior. Air-permeability pressure transients, recorded during constant mass flux injections, have been analyzed using a numerical inversion procedure to identify fracture permeability and porosity. Dipole gas tracer tests have also been conducted from the same boreholes used for air-permeability testing. Mass breakthrough data has been analyzed using a random walk particle-tracking model, with a dispersivity that is a function of the advective velocity. The estimated fracture porosity using the tracer test and air-injection test data ranges from .001 to .015. These values are an order of magnitude greater than the values estimated by others using hydraulically estimated fracture apertures. The estimates of porosity made using air-permeability test data are shown to be highly sensitive to formation heterogeneity. Uncertainty analyses performed on the gas tracer test results show high confidence in the parameter estimates made.

B.M. Freifeild

2001-10-18T23:59:59.000Z

353

Modeling interfacial fracture in Sierra.  

SciTech Connect (OSTI)

This report summarizes computational efforts to model interfacial fracture using cohesive zone models in the SIERRA/SolidMechanics (SIERRA/SM) finite element code. Cohesive surface elements were used to model crack initiation and propagation along predefined paths. Mesh convergence was observed with SIERRA/SM for numerous geometries. As the funding for this project came from the Advanced Simulation and Computing Verification and Validation (ASC V&V) focus area, considerable effort was spent performing verification and validation. Code verification was performed to compare code predictions to analytical solutions for simple three-element simulations as well as a higher-fidelity simulation of a double-cantilever beam. Parameter identification was conducted with Dakota using experimental results on asymmetric double-cantilever beam (ADCB) and end-notched-flexure (ENF) experiments conducted under Campaign-6 funding. Discretization convergence studies were also performed with respect to mesh size and time step and an optimization study was completed for mode II delamination using the ENF geometry. Throughout this verification process, numerous SIERRA/SM bugs were found and reported, all of which have been fixed, leading to over a 10-fold increase in convergence rates. Finally, mixed-mode flexure experiments were performed for validation. One of the unexplained issues encountered was material property variability for ostensibly the same composite material. Since the variability is not fully understood, it is difficult to accurately assess uncertainty when performing predictions.

Brown, Arthur A.; Ohashi, Yuki; Lu, Wei-Yang; Nelson, Stacy A. C.; Foulk, James W.,; Reedy, Earl David,; Austin, Kevin N.; Margolis, Stephen B.

2013-09-01T23:59:59.000Z

354

Identifying Fracture Types and Relative Ages Using Fluid Inclusion Stratigraphy  

SciTech Connect (OSTI)

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.

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

2008-06-30T23:59:59.000Z

355

A STATISTICAL FRACTURE MECHANICS APPROACH TO THE STRENGTH OF BRITTLE ROCK  

E-Print Network [OSTI]

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

Ratigan, J.L.

2010-01-01T23:59:59.000Z

356

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

E-Print Network [OSTI]

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

Doe, T.

2010-01-01T23:59:59.000Z

357

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

E-Print Network [OSTI]

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

Wessling, S.

2009-01-01T23:59:59.000Z

358

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

E-Print Network [OSTI]

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

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

2010-01-01T23:59:59.000Z

359

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

E-Print Network [OSTI]

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

Cappa, F.

2009-01-01T23:59:59.000Z

360

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

E-Print Network [OSTI]

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

Nelson, J.T.

2009-01-01T23:59:59.000Z

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


361

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

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

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

362

Fracture behavior of high-burnup spent-fuel cladding  

SciTech Connect (OSTI)

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

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

1983-10-01T23:59:59.000Z

363

Corporate bodies and chemical bonds : an STS analysis of natural gas development in the United States  

E-Print Network [OSTI]

Natural gas extraction in the United States in the early 21st century has transformed social, physical, legal and biological landscapes. The technique of hydraulic fracturing, which entails the high-pressure injection into ...

Wylie, Sara Ann

2011-01-01T23:59:59.000Z

364

CT measurements of two-phase flow in fractured porous media  

SciTech Connect (OSTI)

The simulation of flow in naturally fractured reservoirs commonly divides the reservoir into two continua - the matrix system and the fracture system. Flow equations are written presuming that the primary flow between grid blocks occurs through the fracture system and that the primary fluid storage is in the matrix system. The dual porosity formulation of the equations assumes that there is no flow between matrix blocks while the dual permeability formulation allows fluid movement between matrix blocks. Since most of the fluid storage is contained in the matrix, recovery is dominated by the transfer of fluid from the matrix to the high conductivity fractures. The physical mechanisms influencing this transfer have been evaluated primarily through numerical studies. Relatively few experimental studies have investigated the transfer mechanisms. Early studies focused on the prediction of reservoir recoveries from the results of scaled experiments on single reservoir blocks. Recent experiments have investigated some of the mechanisms that are dominant in gravity drainage situations and in small block imbibition displacements. The mechanisms active in multiphase flow in fractured media need to be further illuminated, since some of the experimental results appear to be contradictory. This report describes the design, construction, and preliminary results of an experiment that studies imbibition displacement in two fracture blocks. Multiphase (oil/water) displacements will be conducted at the same rate on three core configurations. The configurations are a compact core, a two-block system with a 1 mm spacer between the blocks, and a two-block system with no spacer. The blocks are sealed in epoxy so that saturation measurements can be made throughout the displacement experiments using a Computed Tomography (CT) scanner.

Hughes, R.G.; Brigham, W.E.; Castanier, L.M.

1997-06-01T23:59:59.000Z

365

Modelling of steady-state fluid flow in 3D fractured isotropic porous media: Application to effective permeability calculation  

E-Print Network [OSTI]

industrial applications such as: underground radioactive waste repositories, natural oil/gas recovery, geological CO2 storage, geothermal energy, etc. However, determining effective permeability for fractured and geotechnical engineers. Effective continuum is a simple and efficient approach to study the macroscopic

Paris-Sud XI, Université de

366

IPIRG programs - advances in pipe fracture technology  

SciTech Connect (OSTI)

This paper presents an overview of the advances made in fracture control technology as a result of the research performed in the International Piping Integrity Research Group (IPIRG) program. The findings from numerous experiments and supporting analyses conducted to investigate the behavior of circumferentially flawed piping and pipe systems subjected to high-rate loading typical of seismic events are summarized. Topics to be discussed include; (1) Seismic loading effects on material properties, (2) Piping system behavior under seismic loads, (3) Advances in elbow fracture evaluations, and (4) {open_quotes}Real{close_quotes} piping system response. The presentation for each topic will be illustrated with data and analytical results. In each case, the state-of-the-art in fracture mechanics prior to the first IPIRG program will be contrasted with the state-of-the-art at the completion of the IPIRG-2 program.

Wilkowski, G.; Olson, R.; Scott, P. [Batelle, Columbus, OH (United States)

1997-04-01T23:59:59.000Z

367

On the fracture toughness of advanced materials  

SciTech Connect (OSTI)

Few engineering materials are limited by their strength; rather they are limited by their resistance to fracture or fracture toughness. It is not by accident that most critical structures, such as bridges, ships, nuclear pressure vessels and so forth, are manufactured from materials that are comparatively low in strength but high in toughness. Indeed, in many classes of materials, strength and toughness are almost mutually exclusive. In the first instance, such resistance to fracture is a function of bonding and crystal structure (or lack thereof), but can be developed through the design of appropriate nano/microstructures. However, the creation of tough microstructures in structural materials, i.e., metals, polymers, ceramics and their composites, is invariably a compromise between resistance to intrinsic damage mechanisms ahead of the tip of a crack (intrinsic toughening) and the formation of crack-tip shielding mechanisms which principally act behind the tip to reduce the effective 'crack-driving force' (extrinsic toughening). Intrinsic toughening is essentially an inherent property of a specific microstructure; it is the dominant form of toughening in ductile (e.g., metallic) materials. However, for most brittle (e.g., ceramic) solids, and this includes many biological materials, it is largely ineffective and toughening conversely must be developed extrinsically, by such shielding mechanisms as crack bridging. From a fracture mechanics perspective, this results in toughening in the form of rising resistance-curve behavior where the fracture resistance actually increases with crack extension. The implication of this is that in many biological and high-strength advanced materials, toughness is developed primarily during crack growth and not for crack initiation. This is an important realization yet is still rarely reflected in the way that toughness is measured, which is invariably involves the use of single-value (crack-initiation) parameters such as the fracture toughness K{sub Ic}.

Launey, Maximilien E.; Ritchie, Robert O.

2008-11-24T23:59:59.000Z

368

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

E-Print Network [OSTI]

cooling of the fracture surfaces results in a significant opening of the fracture, which would influence the rate of geothermal

Wessling, S.

2009-01-01T23:59:59.000Z

369

Uncertainty analysis for probabilistic pipe fracture evaluations in LBB applications  

SciTech Connect (OSTI)

During the NRC`s Short Cracks in Piping and Piping Welds Program at Battelle, a probabilistic methodology was developed to conduct fracture evaluations of circumferentially cracked pipes for application to leak-rate detection. Later, in the IPIRG-2 program, several parameters that may affect leak-before-break and other pipe flaw evaluations were identified. This paper presents new results from several uncertainty analyses to evaluate the effects of normal operating stresses, normal plus safe-shutdown earthquake stresses, off-centered cracks, restraint of pressure-induced bending, and dynamic and cyclic loading rates on the conditional failure probability of pipes. systems in BWR and PWR. For each parameter, the sensitivity to conditional probability of failure and hence, its importance on probabilistic leak-before-break evaluations were determined.

Rahman, S.; Ghadiali, N.; Wilkowski, G.

1997-04-01T23:59:59.000Z

370

On equivalence of thinning fluids used for hydraulic fracturing  

E-Print Network [OSTI]

The paper aims to answer the question: if and how non-Newtonian fluids may be compared in their mechanical action when used for hydraulic fracturing? By employing the modified formulation of the PKN problem we obtain its simple analytical solutions in the cases of perfectly plastic and Newtonian fluids. Since the results for shear thinning fluids are intermediate between those for these cases, the obtained equation for the fracture length suggests a criterion of the equivalence of various shear thinning fluids for the problem of hydraulic fractures. We assume fluids equivalent in their hydrofracturing action, when at a reference time they produce fractures of the same length. The equation for the fracture length translates the equivalence in terms of the hydraulic fracture length and treatment time into the equivalence in terms of the properties of a fracturing fluid (behavior and consistency indices). Analysis shows that the influence of the consistency and behavior indices on the fracture length, particle v...

Linkov, Alexander

2012-01-01T23:59:59.000Z

371

How can we use one fracture to locate another?  

E-Print Network [OSTI]

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

Poliannikov, Oleg V.

2011-01-01T23:59:59.000Z

372

FRACTURE AND HYDROLOGY DATA FROM FIELD STUDIES AT STRIPA, SWEDEN  

E-Print Network [OSTI]

An Approach to the Fracture Hydrology at Stripa, PreliminaryRocks. On Recent Trends in Hydrology, Special PublicationsDE86 013586 W FRACTURE AND HYDROLOGY DATA FROM FIELD STUDIES

Gale, J.E.

2010-01-01T23:59:59.000Z

373

Experimental Study of Acid Fracture Conductivity of Austin Chalk Formation  

E-Print Network [OSTI]

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

Nino Penaloza, Andrea

2013-05-01T23:59:59.000Z

374

Development and testing of an advanced acid fracture conductivity apparatus  

E-Print Network [OSTI]

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

Zou, ChunLei

2006-08-16T23:59:59.000Z

375

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.

376

Effectiveness of microseismic monitoring for optimizing hydraulic fracturing in California  

E-Print Network [OSTI]

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

Alampi, Ann M

2014-01-01T23:59:59.000Z

377

Incorporating Rigorous Height Determination into Unified Fracture Design  

E-Print Network [OSTI]

; height, length and width. Unified fracture design (UFD) offers a method to determine the fracture dimensions providing the maximum productivity index for a specific proppant amount. Then, in order to achieve the maximum productivity index, the treatment...

Pitakbunkate, Termpan

2010-10-12T23:59:59.000Z

378

Hydraulic Fracture Monitoring: A Jonah Field Case Study  

E-Print Network [OSTI]

Hydraulic fracturing involves the injection of a fluid to fracture oil and gas reservoirs, and thus increase their permeability. The process creates numerous microseismic events, which can be used to monitor subsurface ...

Seher, T.

2011-01-01T23:59:59.000Z

379

Fractional Diffusion Modeling of Electromagnetic Induction in Fractured Rocks  

E-Print Network [OSTI]

-2 km, a zone where pores and fractures over various length scales are highly complicated. Spatial confinement of fluid or electric charge transport by the fractal geometry gives rise to interesting dynamic processes within the pore space and fractures...

Ge, Jianchao

2014-08-11T23:59:59.000Z

380

Selection of fracture fluid for stimulating tight gas reservoirs  

E-Print Network [OSTI]

..........................................51 6 Water Fracture Fluid Description ..............................................................56 7 Gel Fracture Fluid Description ..................................................................56 8 Proppant Description... Based on Proppant Concentration ........................66 24 Cumulative Frequency Distribution for 3-Year Cumulative Gas Production for Both Groups and Both Treatments (Carthage...

Malpani, Rajgopal Vijaykumar

2007-04-25T23:59:59.000Z

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


381

Finite Difference Modeling of Seismic Responses to Intersecting Fracture Sets  

E-Print Network [OSTI]

Fractured reservoir characterization is becoming increasingly important for the petroleum industry. Currentmethods for this task are developed based on effectivemedia theory, which assumes the cracks or fractures in a ...

Chi, Shihong

2006-01-01T23:59:59.000Z

382

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

SciTech Connect (OSTI)

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.

Huang, Hai; Plummer, Mitchell; Podgorney, Robert

2013-02-01T23:59:59.000Z

383

Fracture Toughness Prediction for MWCNT Reinforced Ceramics  

SciTech Connect (OSTI)

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.

Henager, Charles H.; Nguyen, Ba Nghiep

2013-09-01T23:59:59.000Z

384

HFIR vessel probabilistic fracture mechanics analysis  

SciTech Connect (OSTI)

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

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

1997-01-01T23:59:59.000Z

385

Compartmentalization analysis using discrete fracture network models  

SciTech Connect (OSTI)

This paper illustrates how Discrete Fracture Network (DFN) technology can serve as a basis for the calculation of reservoir engineering parameters for the development of fractured reservoirs. It describes the development of quantitative techniques for defining the geometry and volume of structurally controlled compartments. These techniques are based on a combination of stochastic geometry, computational geometry, and graph theory. The parameters addressed are compartment size, matrix block size and tributary drainage volume. The concept of DFN models is explained and methodologies to compute these parameters are demonstrated.

La Pointe, P.R.; Eiben, T.; Dershowitz, W. [Golder Associates Inc., Redmond, WA (United States); Wadleigh, E. [Marathon Oil Company, Midland, TX (United States). Mid-Continent Region Production

1997-12-31T23:59:59.000Z

386

Compartmentalization analysis using discrete fracture network models  

SciTech Connect (OSTI)

This paper illustrates how Discrete Fracture Network (DFN) technology can serve as a basis for the calculation of reservoir engineering parameters for the development of fractured reservoirs. It describes the development of quantitative techniques for defining the geometry and volume of structurally controlled compartments. These techniques are based on a combination of stochastic geometry, computational geometry, and graph the theory. The parameters addressed are compartment size, matrix block size and tributary drainage volume. The concept of DFN models is explained and methodologies to compute these parameters are demonstrated.

La Pointe, P.R.; Eiben, T.; Dershowitz, W. [Golder Associates, Redmond, VA (United States); Wadleigh, E. [Marathon Oil Co., Midland, TX (United States)

1997-08-01T23:59:59.000Z

387

Application of a 3D hydraulic-fracturing simulator for design of acid-fracturing treatments  

SciTech Connect (OSTI)

Field experience during 1989--90 shows that application of a 3D hydraulic-fracturing simulator increases success of acid-fracturing well treatments. Fracture extension can be limited to the oil-bearing pay, maximum lateral extension can be realized within the height constraint, and acid/rock contact time can be increased by a factor of between 3 and 30. Oil-production response can be improved over other stimulation designs while water-production response can be limited. These methods have been applied in mature waterfloods of the Permian Basin and Cedar Creek anticline.

Morgenthaler, L.N. (Shell Development Co., Houston, TX (United States))

1994-02-01T23:59:59.000Z

388

Detection Science  

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

Chemistry for Measurement and Detection Science Chemistry for Measurement and Detection Science Project Description Chemistry used in measurement and detection science plays a...

389

Experimental and Analytical Research on Fracture Processes in ROck  

SciTech Connect (OSTI)

Experimental studies on fracture propagation and coalescence were conducted which together with previous tests by this group on gypsum and marble, provide information on fracturing. Specifically, different fracture geometries wsere tested, which together with the different material properties will provide the basis for analytical/numerical modeling. INitial steps on the models were made as were initial investigations on the effect of pressurized water on fracture coalescence.

Herbert H.. Einstein; Jay Miller; Bruno Silva

2009-02-27T23:59:59.000Z

390

New fluids help increase effectiveness of hydraulic fracturing  

SciTech Connect (OSTI)

It is important to choose the most effective fluid for hydraulic fracturing a particular formation. Fracturing fluids are used to initiate formation parting, extend the fracture into the reservoir, and to transport and distribute proppant. This paper discusses the fundamental of fluid types, viscosifiers, and fluid rheology.

Ebinger, C.D.; Hunt, E.

1989-06-05T23:59:59.000Z

391

Role of seepage forces on hydraulic fracturing and failure patterns  

E-Print Network [OSTI]

Role of seepage forces on hydraulic fracturing and failure patterns Alexander Rozhko Thesis September 2007 #12;ii Role of seepage forces on hydraulic fracturing and failure patterns Abstract. The mechanical role of seepage forces on hydraulic fracturing and failure patterns was studied both

Paris-Sud XI, Université de

392

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

393

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

394

Poroelastic modeling of fracture-seismic wave interaction  

SciTech Connect (OSTI)

Rock containing a compliant, fluid-filled fracture can be viewed as one case of heterogeneous poroelastic media. When this fracture is subjected to seismic waves, a strong contrast in the elastic stiffness between the fracture itself and the background can result in enhanced grain-scale local fluid flow. Because this flow--relaxing the pressure building up within the fracture--can increase the dynamic compliance of the fracture and change energy dissipation (attenuation), the scattering of seismic waves can be enhanced. Previously, for a flat, infinite fracture, we derived poroelastic seismic boundary conditions that describe the relationship between a finite jump in the stress and displacement across a fracture, expressed as a function of the stress and displacement at the boundaries. In this paper, we use these boundary conditions to determine frequency-dependent seismic wave transmission and reflection coefficients. Fluid-filled fractures with a range of mechanical and hydraulic properties are examined. From parametric studies, we found that the hydraulic permeability of a fracture fully saturated with water has little impact on seismic wave scattering. In contrast, the seismic response of a partially water-saturated fracture and a heterogeneous fracture filled with compliant liquid (e.g., supercritical CO{sub 2}) depended on the fracture permeability.

Nakagawa, Seiji

2008-08-15T23:59:59.000Z

395

San Juan Fracture Characterization Project: Status and current results  

SciTech Connect (OSTI)

The overall objectives of this report are to extend current state-of-the-art 3-D imaging to extract the optimal information for fracture quantification and to develop next generation capability in fracture imaging for true 3-D imaging of the static and dynamic fracture properties.

Majer, E.L.; Daley, T.M.; Myer, L.R.; Nihei, K.; Queen, J.; Sinton, J.; Murphy, J.; Fortuna, M.; Lynn, H.B.; Imhoff, M.A.; Wilson, R.

2001-02-26T23:59:59.000Z

396

CLEAVAGE FRACTURE MICROMECHANISMS RELATED TO WPS EFFECT IN RPV STEEL  

E-Print Network [OSTI]

CLEAVAGE FRACTURE MICROMECHANISMS RELATED TO WPS EFFECT IN RPV STEEL S. R. Bordet1 , B. Tanguy1 , S by warm pre-stress (WPS) on the cleavage fracture micromechanisms of a 18MND5 (A533B) reactor pressure vessel (RPV) steel. In this purpose, different WPS fracture test results obtained on compact tensile (CT

Boyer, Edmond

397

Introduction Fracture at small length scales is a concern  

E-Print Network [OSTI]

Introduction Fracture at small length scales is a concern in many advanced technologies. Micro. These constrained geometries localize cracking so that fracture may not compromise the structural integrity functions. For example, lo- calized fracture of a dielectric film adjacent to a conducting line

Suo, Zhigang

398

Scaling of fracture length and distributed damage Vladimir Lyakhovsky  

E-Print Network [OSTI]

Scaling of fracture length and distributed damage Vladimir Lyakhovsky The Institute of Earth space scaling except linear relations between fracture length and displacements and thus the determination theoretically of the strength of a body or structure directly. Self-similarity of a fracture

Lyakhovsky, Vladimir

399

Fracture patterns in thin films and multilayers Alex A. Volinsky  

E-Print Network [OSTI]

Fracture patterns in thin films and multilayers Alex A. Volinsky University of South Florida, excessive residual and externally applied stresses cause film fracture. In the case of tensile stress is the key for causing thin film fracture, either in tension, or compression, it is the influence

Volinsky, Alex A.

400

Monitoring of Fracture Cri0cal Steel Bridges  

E-Print Network [OSTI]

#12;Monitoring of Fracture Cri0cal Steel Bridges: Acous0c Emission Sensors Fracture System Needs to Iden0fy: · Crack Ini0a0on · Crack Propaga0on · Weld Fracture Advanced Warning of Structural Distress #12;Technology Selec0on: Acous0c

Minnesota, University of

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


401

Structured Deformations as Energy Minimizers in Models of Fracture and  

E-Print Network [OSTI]

Structured Deformations as Energy Minimizers in Models of Fracture and Hysteresis R. Choksi and for a bar experiencing both smooth exten- sion and macroscopic fractures then are determined, and applications to the shearing of single crystals and to the cohesive fracture of solids are discussed. Yield

402

Automatic Fracture Reduction Thomas Albrecht and Thomas Vetter  

E-Print Network [OSTI]

Automatic Fracture Reduction Thomas Albrecht and Thomas Vetter University of Basel Abstract. We segmented from CT scans. The result of this virtual fracture reduction is intended to be used an operation plan. We propose to achieve automatic fracture reduction by fitting the bone fragments

Vetter, Thomas

403

Fracture aperture reconstruction and determination of hydrological properties: a  

E-Print Network [OSTI]

Fracture aperture reconstruction and determination of hydrological properties: a case study for fracture aperture reconstruction. The rst one is a correlation technique that estimates the normal aper techniques are applied to discontinuities extracted from a core drilled down to 20 m in a fractured marl

Toussaint, Renaud

404

Geometric fracture modeling in BOLT Jeffrey Hellrung1  

E-Print Network [OSTI]

Geometric fracture modeling in BOLT Jeffrey Hellrung1 Andrew Selle2 Arthur Shek2 Eftychios Sifakis1 from the un-fractured model. 2 Crack geometry generation The input to our system consists of a closed triangulated surface defining the (uncut) solid object to be fractured and one or more ad- ditional

Liblit, Ben

405

Fracture Toughness of MDF and other Materials with Fiber Bridging  

E-Print Network [OSTI]

Fracture Toughness of MDF and other Materials with Fiber Bridging Noah Matsumoto and John A. Nairn* ABSTRACT We measured the fracture toughness of MDF panels with two different densities by using crack propagation experiments and energy-based fracture mechanics. The two challenges were to identify the energy

Nairn, John A.

406

EXPERIMENTAL INVESTIGATION OF BOILING HEAT CONVECTION IN A FRACTURE  

E-Print Network [OSTI]

EXPERIMENTAL INVESTIGATION OF BOILING HEAT CONVECTION IN A FRACTURE A REPORT SUBMITTED between heat conduction and heat convection with boiling flow in a rock fracture. An experimental coefficient. This coefficient is the proportionality factor between the heat flux to a fracture surface

Stanford University

407

SCALING OF FRACTURE SYSTEMS IN GEOLOGICAL MEDIA E. Bonnet,1  

E-Print Network [OSTI]

SCALING OF FRACTURE SYSTEMS IN GEOLOGICAL MEDIA E. Bonnet,1 O. Bour,2 N. E. Odling,1,3 P. Davy,2 I. Main,4 P. Cowie,4 and B. Berkowitz5 Abstract. Scaling in fracture systems has become an active field spread widely through the literature. Although it is rec- ognized that some fracture systems are best

Cowie, Patience

408

Fibre Based Modeling of Wood Dynamics and Fracture  

E-Print Network [OSTI]

Fibre Based Modeling of Wood Dynamics and Fracture by Sean Meiji Sutherland B.Sc., The University for the simulation of the dynamics and fracturing char- acteristics of wood, specifically its anisotropic behaviour bundles of fibres. Additionally, we describe the conditions under which fracture occurs in the material

Bridson, Robert

409

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

E-Print Network [OSTI]

In vitro fracture toughness of human dentin V. Imbeni,1 R. K. Nalla,1 C. Bosi,1 J. H. Kinney,2 R. O August 2002 Abstract: The in vitro fracture toughness of human dentin has been reported measured crit- ical stress intensity, Kc, for the onset of unstable fracture along an orientation

Ritchie, Robert

410

Fracture surface energy of the Punchbowl fault, San Andreas system  

E-Print Network [OSTI]

Fracture surface energy of the Punchbowl fault, San Andreas system Judith S. Chester1 , Frederick M. Chester1 & Andreas K. Kronenberg1 Fracture energy is a form of latent heat required to create weakening1­3 . Fracture energy has been estimated from seismological and experimental rock deformation data4

Chester, Frederick M.

411

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

412

The use of seismic anisotropy for characterizing subsurface fracture ori-  

E-Print Network [OSTI]

The use of seismic anisotropy for characterizing subsurface fracture ori- entations and intensity anisotropy as a routine technique for fracture characterization is partly because of its inability to pro- vide information about sizes and vol- ume of fractures. Although both grain-scale micro

Edinburgh, University of

413

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

414

Femoral neck fracture prediction by anisotropic yield criteria  

E-Print Network [OSTI]

Femoral neck fracture prediction by anisotropic yield criteria M. Tellache a , b , M. Pithioux and increases its porosity. Hip fractures are the more recurrent consequences of osteoporosis, and are the cause of morbidity and increase the rate of mortality. The fracture risk due to osteoporosis, is undertaken with Dual

Paris-Sud XI, Université de

415

Creation and Impairment of Hydraulic Fracture Conductivity in Shale Formations  

E-Print Network [OSTI]

Multi-stage hydraulic fracturing is the key to the success of many shale gas and shale oil reservoirs. The main objectives of hydraulic fracturing in shale are to create artificial fracture networks that are conductive for oil and gas flow...

Zhang, Junjing

2014-07-10T23:59:59.000Z

416

Improved Microseismicity Detection During Newberry EGS Stimulations  

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

Effective enhanced geothermal systems (EGS) require optimal fracture networks for efficient heat transfer between hot rock and fluid. Microseismic mapping is a key tool used to infer the subsurface fracture geometry. Traditional earthquake detection and location techniques are often employed to identify microearthquakes in geothermal regions. However, most commonly used algorithms may miss events if the seismic signal of an earthquake is small relative to the background noise level or if a microearthquake occurs within the coda of a larger event. Consequently, we have developed a set of algorithms that provide improved microearthquake detection. Our objective is to investigate the microseismicity at the DOE Newberry EGS site to better image the active regions of the underground fracture network during and immediately after the EGS stimulation. Detection of more microearthquakes during EGS stimulations will allow for better seismic delineation of the active regions of the underground fracture system. This improved knowledge of the reservoir network will improve our understanding of subsurface conditions, and allow improvement of the stimulation strategy that will optimize heat extraction and maximize economic return.

Templeton, Dennise

417

Improved Microseismicity Detection During Newberry EGS Stimulations  

SciTech Connect (OSTI)

Effective enhanced geothermal systems (EGS) require optimal fracture networks for efficient heat transfer between hot rock and fluid. Microseismic mapping is a key tool used to infer the subsurface fracture geometry. Traditional earthquake detection and location techniques are often employed to identify microearthquakes in geothermal regions. However, most commonly used algorithms may miss events if the seismic signal of an earthquake is small relative to the background noise level or if a microearthquake occurs within the coda of a larger event. Consequently, we have developed a set of algorithms that provide improved microearthquake detection. Our objective is to investigate the microseismicity at the DOE Newberry EGS site to better image the active regions of the underground fracture network during and immediately after the EGS stimulation. Detection of more microearthquakes during EGS stimulations will allow for better seismic delineation of the active regions of the underground fracture system. This improved knowledge of the reservoir network will improve our understanding of subsurface conditions, and allow improvement of the stimulation strategy that will optimize heat extraction and maximize economic return.

Templeton, Dennise

2013-11-01T23:59:59.000Z

418

Improved Microseismicity Detection During Newberry EGS Stimulations  

SciTech Connect (OSTI)

Effective enhanced geothermal systems (EGS) require optimal fracture networks for efficient heat transfer between hot rock and fluid. Microseismic mapping is a key tool used to infer the subsurface fracture geometry. Traditional earthquake detection and location techniques are often employed to identify microearthquakes in geothermal regions. However, most commonly used algorithms may miss events if the seismic signal of an earthquake is small relative to the background noise level or if a microearthquake occurs within the coda of a larger event. Consequently, we have developed a set of algorithms that provide improved microearthquake detection. Our objective is to investigate the microseismicity at the DOE Newberry EGS site to better image the active regions of the underground fracture network during and immediately after the EGS stimulation. Detection of more microearthquakes during EGS stimulations will allow for better seismic delineation of the active regions of the underground fracture system. This improved knowledge of the reservoir network will improve our understanding of subsurface conditions, and allow improvement of the stimulation strategy that will optimize heat extraction and maximize economic return.

Templeton, Dennise

2013-10-01T23:59:59.000Z

419

Boiling Radial Flow in Fractures of Varying  

E-Print Network [OSTI]

the surface, within the matrix. The depth of boiling was a function of injection rate, thermal power supplied coupled to injection rate into the fracture. However, for porous surfaces, heat flux, and associated values of excess temperature and a boiling convection coefficient exhibited variation with injection rate

Stanford University

420

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

E-Print Network [OSTI]

) ............................................................................ 51 Figure B.9: Fracture Conductivity Behavior (Polymer Concentration = 50 lb/Mgal and Gas Rate = 0.5 slm) ............................................................................ 52 Figure B.10: Fracture Conductivity Behavior (Polymer... documented in API RP-61 (1989). The recommended conditions and procedure for the test includes loading a known proppant concentration (generally 2 lb/ft2) uniformly between two steel pistons at ambient temperature, maintaining closure stress for 15 minutes...

Marpaung, Fivman

2008-10-10T23:59:59.000Z

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


421

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

E-Print Network [OSTI]

) ............................................................................ 51 Figure B.9: Fracture Conductivity Behavior (Polymer Concentration = 50 lb/Mgal and Gas Rate = 0.5 slm) ............................................................................ 52 Figure B.10: Fracture Conductivity Behavior (Polymer... documented in API RP-61 (1989). The recommended conditions and procedure for the test includes loading a known proppant concentration (generally 2 lb/ft2) uniformly between two steel pistons at ambient temperature, maintaining closure stress for 15 minutes...

Marpaung, Fivman

2009-05-15T23:59:59.000Z

422

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

E-Print Network [OSTI]

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

Peirce, Anthony

423

A Triple-Porosity Model for Fractured Horizontal Wells  

E-Print Network [OSTI]

. The model consists of three contiguous porous media: the matrix, less permeable micro-fractures and more permeable macro-fractures. Only the macro-fractures produce to the well while they are fed by the micro-fractures only. Consequently, the matrix feeds... the micro-fractures only. Therefore, the flow is sequential from one medium to the other. Four sub-models are derived based on the interporosity flow assumption between adjacent media, i.e., pseudosteady state or transient flow assumption. These are fully...

Alahmadi, Hasan Ali H.

2010-10-12T23:59:59.000Z

424

Advanced hydraulic fracturing methods to create in situ reactive barriers  

SciTech Connect (OSTI)

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

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

1997-12-31T23:59:59.000Z

425

On the effect of x-ray irradiation on the deformation and fracture behavior of human cortical bone  

SciTech Connect (OSTI)

In situ mechanical testing coupled with imaging using high-energy synchrotron x-ray diffraction or tomography imaging is gaining in popularity as a technique to investigate micrometer and even sub-micrometer deformation and fracture mechanisms in mineralized tissues, such as bone and teeth. However, the role of the irradiation in affecting the nature and properties of the tissue is not always taken into account. Accordingly, we examine here the effect of x-ray synchrotron-source irradiation on the mechanistic aspects of deformation and fracture in human cortical bone. Specifically, the strength, ductility and fracture resistance (both work-of-fracture and resistance-curve fracture toughness) of human femoral bone in the transverse (breaking) orientation were evaluated following exposures to 0.05, 70, 210 and 630 kGy irradiation. Our results show that the radiation typically used in tomography imaging can have a major and deleterious impact on the strength, post-yield behavior and fracture toughness of cortical bone, with the severity of the effect progressively increasing with higher doses of radiation. Plasticity was essentially suppressed after as little as 70 kGy of radiation; the fracture toughness was decreased by a factor of five after 210 kGy of radiation. Mechanistically, the irradiation was found to alter the salient toughening mechanisms, manifest by the progressive elimination of the bone's capacity for plastic deformation which restricts the intrinsic toughening from the formation 'plastic zones' around crack-like defects. Deep-ultraviolet Raman spectroscopy indicated that this behavior could be related to degradation in the collagen integrity.

Barth, Holly D.; Launey, Maximilien E.; McDowell, Alastair A.; Ager III, Joel W.; Ritchie, Robert O.

2010-01-10T23:59:59.000Z

426

Linear elastic fracture mechanics predicts the propagation distance of frictional slip  

E-Print Network [OSTI]

When a frictional interface is subject to a localized shear load, it is often (experimentally) observed that local slip events initiate at the stress concentration and propagate over parts of the interface by arresting naturally before reaching the edge. We develop a theoretical model based on linear elastic fracture mechanics to describe the propagation of such precursory slip. The model's prediction of precursor lengths as a function of external load is in good quantitative agreement with laboratory experiments as well as with dynamic simulations, and provides thereby evidence to recognize frictional slip as a fracture phenomenon. We show that predicted precursor lengths depend, within given uncertainty ranges, mainly on the kinetic friction coefficient, and only weakly on other interface and material parameters. By simplifying the fracture mechanics model we also reveal sources for the observed non-linearity in the growth of precursor lengths as a function of the applied force. The discrete nature of precursors as well as the shear tractions caused by frustrated Poisson's expansion are found to be the dominant factors. Finally, we apply our model to a different, symmetric set-up and provide a prediction of the propagation distance of frictional slip for future experiments.

David S. Kammer; Mathilde Radiguet; Jean-Paul Ampuero; Jean-François Molinari

2014-08-18T23:59:59.000Z

427

Time-resolved measurement of photon emission during fast crack propagation in three-point bending fracture of silica glass and soda lime glass  

SciTech Connect (OSTI)

Simultaneous time-resolved measurements of photon emission (PE) and fast crack propagation upon bending fracture were conducted in silica glass and soda lime glass. Observation of fracture surfaces revealed that macroscopic crack propagation behavior was similar between the silica glass and soda lime glass when fracture loads for these specimens were comparable and cracks propagated without branching. However, a large difference in the PE characteristics was found between the two glasses. In silica glass, PE (645–655?nm) was observed during the entire crack propagation process, whereas intense PE (430–490?nm and 500–600?nm) was observed during the initial stages of propagation. In contrast, only weak PE was detected in soda lime glass. These results show that there is a large difference in the atomic processes involved in fast crack propagation between these glasses, and that PE can be used to study brittle fracture on the atomic scale.

Shiota, Tadashi, E-mail: tshiota@ceram.titech.ac.jp; Sato, Yoshitaka; Yasuda, Kouichi [Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, 2-12-1-S7-13 Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)] [Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, 2-12-1-S7-13 Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)

2014-03-10T23:59:59.000Z

428

Stress wave propagationin the site 12 hydraulic/explosive fracturing experiment  

SciTech Connect (OSTI)

The Site 12 experiment was a heavily instrumented field event performed to examine the hydraulic/explosive fracturing concept for preparing an underground oil shale bed for true in situ processing. One of the key phases of this fracturing concept is the blasting operation which involves the insertion and detonation of slurry explosive in a pre-formed system of hydrofractures. To obtain a sound understanding of the nature of the blasting operations, a rather extensive array of stress gages, accelerometers, and time-of-arrival gages was installed in the rock mass in the vacinity of the explosive to monitor the dynamic events initiated by the detonation. These gages provided considerable amounts of information which were useful in evaluating overall results of the experiment. Details of the gage array, of the data, of analysis methods, and of the results and conclusions are considered in the report.

Boade, R. R.; Reed, R. P.

1980-05-01T23:59:59.000Z

429

Impact fracture behavior of HT9 duct  

SciTech Connect (OSTI)

Ferritic alloys are known to undergo a ductile-brittle transition as the test temperature is decreased. This inherent problem has limited their applications to reactor component materials subjected to low neutron exposures. However, the excellent resistance to void swelling exhibited by these alloys has led to choosing the materials as candidate materials for fast and fusion reactor applications. Despite the ductile-brittle transition problem, results show that the materials exhibit superior resistance to fracture under very high neutron fluences at irradiation temperatures above 380{degrees}C. Impact testing on FFTF duct sections of HT9 indicates that HT9 ducts have adequate fracture toughness at much higher temperatures for handling operations at room temperature and refueling operations.

Huang, F.H. [Westinghouse Hanford Co., Richland, WA (United States); Gelles, D.S. [Pacific Northwest Lab., Richland, WA (United States)

1994-07-01T23:59:59.000Z

430

Fracture simulation for zirconia toughened alumina microstructure  

E-Print Network [OSTI]

Purpose - The purpose of this paper is to describe finite element modelling for fracture and fatigue behaviour of zirconia toughened alumina microstructures. Design/methodology/approach - A two-dimensional finite element model is developed with an actual $Al{_2}O{_3}$ - 10 vol% $ZrO{_2}$ microstructure. A bilinear, time-independent cohesive zone law is implemented for describing fracture behaviour of grain boundaries. Simulation conditions are similar to those found at contact between a head and a cup of hip prosthesis. Residual stresses arisen from the mismatch of thermal coefficient between grains are determined. Then, effects of a micro-void and contact stress magnitude are investigated with models containing residual stresses. For the purpose of simulating fatigue behaviour, cyclic loadings are applied to the models. Findings - Results show that crack density is gradually increased with increasing magnitude of contact stress or number of fatigue cycles. It is also identified that a micro-void brings about...

Kim, Kyungmok; Forest, Bernard

2013-01-01T23:59:59.000Z

431

Correlating toughness and roughness in ductile fracture  

E-Print Network [OSTI]

Three dimensional calculations of ductile crack growth under mode I plane strain, small scale yielding conditions are carried out using an elastic-viscoplastic constitutive relation for a progres- sively cavitating plastic solid with two populations of void nucleating second phase particles. Full field solutions are obtained for three dimensional material microstructures characterized by ran- dom distributions of void nucleating particles. Crack growth resistance curves and fracture surface roughness statistics are calculated using standard procedures. The range of void nucleating particle volume fractions considered give rise to values of toughness, JIC, that vary by a factor of four. For all volume fractions considered, the computed fracture surfaces are self-affine over a size range of about two orders of magnitude with a roughness exponent of 0.54 $\\pm$ 0.03. For small void nucleating particle volume fractions, the mean large particle spacing serves as a single dominant length scale. In this regime, the c...

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

2013-01-01T23:59:59.000Z

432

Characterization of fracture networks for fluid flow analysis  

SciTech Connect (OSTI)

The analysis of fluid flow through fractured rocks is difficult because the only way to assign hydraulic parameters to fractures is to perform hydraulic tests. However, the interpretation of such tests, or ''inversion'' of the data, requires at least that we know the geometric pattern formed by the fractures. Combining a statistical approach with geophysical data may be extremely helpful in defining the fracture geometry. Cross-hole geophysics, either seismic or radar, can provide tomograms which are pixel maps of the velocity or attenuation anomalies in the rock. These anomalies are often due to fracture zones. Therefore, tomograms can be used to identify fracture zones and provide information about the structure within the fracture zones. This structural information can be used as the basis for simulating the degree of fracturing within the zones. Well tests can then be used to further refine the model. Because the fracture network is only partially connected, the resulting geometry of the flow paths may have fractal properties. We are studying the behavior of well tests under such geometry. Through understanding of this behavior, it may be possible to use inverse techniques to refine the a priori assignment of fractures and their conductances such that we obtain the best fit to a series of well test results simultaneously. The methodology described here is under development and currently being applied to several field sites. 4 refs., 14 figs.

Long, J.C.S.; Billaux, D.; Hestir, K.; Majer, E.L.; Peterson, J.; Karasaki, K.; Nihei, K.; Gentier, S.; Cox, L.

1989-06-01T23:59:59.000Z

433

How intense quality control improves hydraulic fracturing  

SciTech Connect (OSTI)

Not unlike the subject of Forced Closure, Intense Quality Control is probably misnamed. What actually is discussed in this article is pilot testing of the fracturing fluids actually pumped at in-situ conditions of temperature and shear. Presented here is development of the need for onsite testing, equipment used, shear and viscosity curves from several jobs showing what went wrong that would otherwise not have been known, and a discussion of borate gel fluids.

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

1996-11-01T23:59:59.000Z

434

Lisburne Formation fracture characterization and flow modeling  

E-Print Network [OSTI]

lead to exponential distrtbutions; multiplicatory processes as they occur in breakage lead 10 to lognormal distributions; and continuity of the process from smallest to largest sizes produces hyperbolic (fractal) distributions. However, a rigorous... of fractures on related outcrops was in the range of 1, 6-1. 8. Brock (1971) stated an important rule of thumb of fractal studies: the linearity on the double logarithmic plot should extend over at least two or three orders of naagnitude ol particle size...

Karpov, Alexandre Valerievich

2001-01-01T23:59:59.000Z

435

Effects of oxygen on fracturing fluids  

SciTech Connect (OSTI)

The stability of polysaccharide gels at high temperature is limited by such factors as pH, mechanical degradation, and oxidants. Oxygen is unavoidably placed in fracturing fluids through dissolution of air. To prevent premature degradation of the fracturing fluid by this oxidant, oxygen scavengers are commonly used. In this paper, the effects of oxygen and various oxygen scavengers on gel stability will be presented. Mechanical removal of oxygen resulted in surprisingly stable fracturing gels at 275 F. However, chemical removal of oxygen gave mixed results. Test data from sodium thiosulfate, sodium sulfite, and sodium erythorbate used as oxygen scavengers/gel stabilizers showed that the efficiency of oxygen removal from gels did not directly coincide with the viscosity retention of the gel, and large excesses of additives were necessary to provide optimum gel stabilization. The inability of some oxygen scavengers to stabilize the gel was the result of products created from the interaction of oxygen with the oxygen scavenger, which in turn, produced species that degraded the gel. The ideal oxygen scavenger should provide superior gel stabilization without creating detrimental side reaction products. Of the materials tested, sodium thiosulfate appeared to be the most beneficial.

Walker, M.L.; Shuchart, C.E.; Yaritz, J.G.; Norman, L.R.

1995-11-01T23:59:59.000Z

436

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

E-Print Network [OSTI]

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

Ritchie, Robert

437

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

E-Print Network [OSTI]

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

Hutchinson, John W.

438

Flow focusing in unsaturated fracture networks: A numerical investigation  

SciTech Connect (OSTI)

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

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

2003-04-17T23:59:59.000Z

439

Microsoft Word - NRAP-TRS-III-003-2014_Characterization of Experimental Fracture Alteration and Fluid Flow in Fractured Natural  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMappingENVIRONMENTALHYDROPOWERFebruarySavebased on an analysis

440

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...

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


441

Hydraulic fracturing and geothermal energy development in Japan  

SciTech Connect (OSTI)

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

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

1982-09-01T23:59:59.000Z

442

Application of the directional hydraulic fracturing at Berezovskaya Mine  

SciTech Connect (OSTI)

The paper analyzes the experimental research of the directional hydraulic fracturing applied for weakening of rocks at Berezovskaya Mine (Kuznetsk Coal Basin) in 2005-2006.

Lekontsev, Y.M.; Sazhin, P.V. [Russian Academy of Sciences, Novosibirsk (Russian Federation). Institute for Mining

2008-05-15T23:59:59.000Z

443

Reflection and transmission coefficients of a fracture in transversely ...  

E-Print Network [OSTI]

The study of the reflection-transmission problem of a fracture plays an ...... material or abrupt changes in COF (Smith, 1996; Anandakrishnan, 1996; Horgan et al.,.

2011-11-28T23:59:59.000Z

444

Determination Of The Orientation Of Open Fractures From Hydrophone VSP  

E-Print Network [OSTI]

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

Lee, Jung Mo

1995-01-01T23:59:59.000Z

445

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

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

Oil Recovery Deepwater Tech Methane Hydrate Field Demo of Eco-Friendly Propped Hydraulic Fractures 11123-23 Primary Performer DaniMer Scientific, LLC (Bainbridge, GA)...

446

Transient pressure behavior of multiple-fractured gas wells  

E-Print Network [OSTI]

with the dimensionless terms C = wk /vkxf and r xf 12 Xf 1/Xf2 where Cr is the dimensionless fracture conductivity and xf 1& is the fracture half-length ratio. fr 12 The symbols, xf1 and xf2, represent the half-length of the primary fracture and the auxiliary fr... actur e, respectively. Results also show that when C & 10, multiple fracture transient pressure behavior is significantly different from that of a single plane fr actur e. A family of type cur ves was constructed using cross-plots of Pwp vs tpx...

Choo, Yew Kai

1985-01-01T23:59:59.000Z

447

Finding Large Aperture Fractures in Geothermal Resource Areas...  

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

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

448

Finding Large Aperture Fractures in Geothermal Resource Areas...  

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

3-D mapping of Large Aperture Fractures (LAF's) * Budget: 679,000 - Phase 2: Drilling - January-December, 2011. * Task 4: Stepout drilling from existing production wells....

449

Studies of Transport Properties of Fractures: Final Report  

SciTech Connect (OSTI)

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.

Stephen R. Brown

2006-06-30T23:59:59.000Z

450

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

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

if fracturing could be used to enhance permeability; and whether dilution of existing fluids with injected water would lower corrosivity enough to allow economic production of...

451

AN APPROACH TO THE FRACTURE HYDROLOGY AT STRIPA: PRELIMINARY RESULTS  

E-Print Network [OSTI]

Geochemistry and Isotope Hydrology of Groundwaters in theAN APPROACH TO THE FRACTURE HYDROLOGY AT STRIPA: PRELIMINARYGeochemistry and Isotope Hydrology of Groundwaters in the

Gale, J.E.

2010-01-01T23:59:59.000Z

452

Characterization Of Fracture Patterns In The Geysers Geothermal...  

Open Energy Info (EERE)

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

453

Characterization of subsurface fracture patterns in the Coso...  

Open Energy Info (EERE)

LibraryAdd to library Conference Proceedings: Characterization of subsurface fracture patterns in the Coso geothermal reservoir by analyzing shear-wave splitting of...

454

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

Open Energy Info (EERE)

Reservoir-Scale Fracture Permeability in the Dixie Valley, Nevada, Geothermal Field Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper:...

455

Fracture Evolution Following a Hydraulic Stimulation within an...  

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

Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir Principal Investigator Peter Rose Energy and Geoscience Institute at the University of Utah Project...

456

Evaluation of subsurface fracture geometry using fluid pressure...  

Open Energy Info (EERE)

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

457

Tracer Methods for Characterizing Fracture Stimulation in Enhanced...  

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

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

458

Fracture Characterization in Enhanced Geothermal Systems by Wellbore...  

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

5 4.6.4 Fracture Characterization in Enhanced Geothermal Systems by Wellbore and Reservoir Analysis Presentation Number: 031 Investigator: Horne, Roland (Stanford University)...

459

Tracer Methods for Characterizing Fracture Stimulation in Enhanced...  

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

80 4.6.7 Tracer Methods for Characterizing Fracture Stimulation in Enhanced Geothermal Systems (EGS) Presentation Number: 034 Investigator: Pruess, Karsten (Lawrence Berkeley...

460

Transitions from Oscillatory to Smooth Fracture Propagation in...  

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

Transitions from Oscillatory to Smooth Fracture Propagation in Viscoelastic Materials Jan 29 2015 10:30 AM - 11:30 AM Yehuda Braiman, Division Staff Computer Science and...

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


461

Tracer Methods for Characterizing Fracture Stimulation in Engineered...  

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

Tracer Methods for Characterizing Fracture Stimulation in Engineered Geothermal Systems (EGS) Karsten Pruess Lawrence Berkeley National Lab. May 19, 2010 This presentation does not...

462

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

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

Joint inversion of electrical and seismic data for Fracture char. and Imaging of Fluid Flow in Geothermal Systems Michael Batzle, PI Colorado School of Mines Track Name: Fluid...

463

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,...

464

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

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

Fracture Network and Fluid Flow Imaging for EGS Applications from Multi-Dimensional Electrical Resistivity Structure Principal Investigator: Philip E. Wannamaker University of Utah...

465

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

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

1 4.6.1 Three-dimensional Modeling of Fracture Clusters in Geothermal Reservoirs Presentation Number: 028 Investigator: Ghassemi, Ahmad (Texas A&M University) Objectives: To...

466

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

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

The Role of Geochemistry and Stress on Fracture Development and Proppant Behavior in EGS Reservoirs Principal Investigator (Joseph Moore) Presenter Name (John McLennan)...

467

A Comprehensive Study Of Fracture Patterns And Densities In The...  

Open Energy Info (EERE)

Study Of Fracture Patterns And Densities In The Geysers Geothermal Reservoir Using Microearthquake Shear-Wave Splitting Tomography Jump to: navigation, search OpenEI Reference...

468

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

Open Energy Info (EERE)

correlations. Downhole measurements of the tracer response exiting from discrete fracture zones permit further characterization of reservoir fluid flow behavior. Tracer...

469

apophyseal ring fractures: Topics by E-print Network  

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

system 4 2 Ring solutions Kolokolnikov, Theodore 90 Self-potential observations during hydraulic fracturing University of California eScholarship Repository Summary: hydraulic...

470

Poroelastic modeling of fracture-seismic wave interaction  

E-Print Network [OSTI]

JCRM All rights reserved. Volume x, Number x, Month 200x, pp.x-x. [Issue paper]. Poroelastic modeling of fracture-seismic wave interaction. Seiji NAKAGAWA.

Toru Takahashi

2009-01-07T23:59:59.000Z

471

Advanced Hydraulic Fracturing Technology for Unconventional Tight Gas Reservoirs  

SciTech Connect (OSTI)

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.

Stephen Holditch; A. Daniel Hill; D. Zhu

2007-06-19T23:59:59.000Z

472

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

E-Print Network [OSTI]

Mar 10, 2014 ... Fractured hydrocarbon reservoirs have been the subject of interest in ...... size. Once a continuous fractal distribution of brine is obtained over ...

santos

473

Hydraulic Fractures: multiscale phenomena, asymptotic and numerical solutions  

E-Print Network [OSTI]

well stimulation Fracturing Fluid Proppant #12;5 Quarries #12;6 Magma flow Tarkastad #12;7 Model EQ 1

Peirce, Anthony

474

Improved fracture toughness of fire resistant composites through rapid curing.  

E-Print Network [OSTI]

??A study on the effect of material and fracture properties of phenolic composites cured with reduced thermal cycle times. These reductions were achieved using various… (more)

Denmead, Ashley

2012-01-01T23:59:59.000Z

475

SciTech Connect: CRACK TIP PLASTICITY AND FRACTURE INITIATION...  

Office of Scientific and Technical Information (OSTI)

N50000* --Metals, Ceramics, & Other Materials; CRACKS; FRACTURE PROPERTIES; METALS BUILDING MATERIALSfracture of metal, crack tip plasticity and initiation criteria for;...

476

INJECTION AND THERMAL BREAKTHROUGH IN FRACTURED GEOTHERMAL RESERVOIRS  

E-Print Network [OSTI]

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

Bodvarsson, Gudmundur S.

2012-01-01T23:59:59.000Z

477

Effective velocities in fractured media: a numerical study using the ...  

E-Print Network [OSTI]

and precise numerical study of effective velocities in fractured structures. ... In this paper, we ..... A final result is that our numerical simulations of P-, SV- and.

2002-03-18T23:59:59.000Z

478

Characterization of fracture reservoirs using static and dynamic data: From sonic and 3D seismic to permeability distribution. Annual report, March 1, 1996--February 28, 1997  

SciTech Connect (OSTI)

In low porosity, low permeability zones, natural fractures are the primary source of permeability which affect both production and injection of fluids. The open fractures do not contribute much to porosity, but they provide an increased drainage network to any porosity. They also may connect the borehole to remote zones of better reservoir characteristics. An important approach to characterizing the fracture orientation and fracture permeability of reservoir formations is one based on the effects of such conditions on the propagation of acoustic and seismic waves in the rock. The project is a study directed toward the evaluation of acoustic logging and 3D-seismic measurement techniques as well as fluid flow and transport methods for mapping permeability anisotropy and other petrophysical parameters for the understanding of the reservoir fracture systems and associated fluid dynamics. The principal application of these measurement techniques and methods is to identify and investigate the propagation characteristics of acoustic and seismic waves in the Twin Creek hydrocarbon reservoir owned by Union Pacific Resources (UPR) and to characterize the fracture permeability distribution using production data. This site is located in the overthrust area of Utah and Wyoming. UPR drilled six horizontal wells, and presently UPR has two rigs running with many established drill hole locations. In addition, there are numerous vertical wells that exist in the area as well as 3D seismic surveys. Each horizontal well contains full FMS logs and MWD logs, gamma logs, etc.

Parra, J.O.; Collier, H.A.; Owen, T.E. [and others

1997-06-01T23:59:59.000Z

479

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

E-Print Network [OSTI]

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

Segatti, Antonio

480

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

E-Print Network [OSTI]

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...

Alghamdi, Abdulwahab

2006-08-16T23:59:59.000Z

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


481

Interpretation of pre- and post-fracturing well tests in a geothermal reservoir  

SciTech Connect (OSTI)

Pre- and post-fracturing well tests in TG-2 well drilled next to the Matsukawa field are interpreted for evaluating effects of a massive hydraulic fracturing treatment. The interpreted data include multiple-step rate tests, a two-step rate test, and falloff tests. Pressure behaviors of massive hydraulic fracturing are matched by a simulator of dynamic fracture option. Fracture parting pressures can be evaluated from the multiple-step rate test data. The multiple-step rates during the massive hydraulic fracturing treatment show that multiple fractures have been induced in sequence. Although the pre-fracturing falloff tests are too short, fracture propagation can be evaluated qualitatively from the falloff data. Interpretation of the falloff test immediately after the MHF suggests that extensive fractures have been created by the MHF, which is verified by simulation. The post-fracturing falloff tests show that the fractures created by the MHF have closed to a great degree.

Arihara, Norio; Fukagawa, Hiroshi; Hyodo, Masami; Abbaszadeh, Maghsood

1995-01-26T23:59:59.000Z

482

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

E-Print Network [OSTI]

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...

Oeth, Cassandra V

2013-11-25T23:59:59.000Z

483

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

484

COMPARING FRACTURE PROPAGATION TESTS AND RELATING TEST RESULTS TO SNOWPACK CHARACTERISTICS  

E-Print Network [OSTI]

COMPARING FRACTURE PROPAGATION TESTS AND RELATING TEST RESULTS TO SNOWPACK CHARACTERISTICS Cameron for a slab and weak layer combination to propagate a fracture. University of Calgary researchers performed propensity. KEYWORDS: fracture propagation, snowpack stability test, extended column test, propagation saw

Jamieson, Bruce

485

On the fracture of human dentin: Is it stress- or strain-controlled?  

E-Print Network [OSTI]

N, Ruse ND. NTP specimen fracture toughness test applied toRO. On the in vitro fracture toughness of human dentin. Jtensile stress and fracture toughness in mild steel. J Mech

Nalla, R.K.; Kinney, J.H.; Ritchie, R.O.

2006-01-01T23:59:59.000Z

486

E-Print Network 3.0 - acute rib fracture Sample Search Results  

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

rib fracture Search Powered by Explorit Topic List Advanced Search Sample search results for: acute rib fracture Page: << < 1 2 3 4 5 > >> 1 Dynamic fracture of granular material...

487

A PURELY NUMERICAL APPROACH FOR ANALYZING FLOW TO A WELL INTERCEPTING A VERTICAL FRACTURE  

E-Print Network [OSTI]

W.R. Effect of vertical fracture on reservoir behavior --of deep, penetrating fractures in the wattenberg Field.flow through a single fracture. PhD Dissertation, Department

Narasimhan, T.N.

2011-01-01T23:59:59.000Z

488

FRACTURE MAPPING IN THE VENTILATION DRIFT AT STRIPA: PROCEDURES AND RESULTS  

E-Print Network [OSTI]

Future Work . RESULTS OF FRACTURE MAPPING AND USE OF DATAFILES. 2.1 Fracture Maps . . . • . . . . . • . . 2.2 Mapping12). 15. An Approach to the Fracture Hydrology at Stripa:

Rouleau, A.

2010-01-01T23:59:59.000Z

489

VALIDITY OF CUBIC LAW FOR FLUID FLOW IN A DEFORMABLE ROCK FRACTURE  

E-Print Network [OSTI]

hydraulic properties of fractures." T^ be published in Water14). 15. An Approach to the Fracture Hydrology at Stripa:Hydraulic Properties of Fractures by P. A. Witherspoon, C.

Witherspoon, P.A.

2010-01-01T23:59:59.000Z

490

Fracture Dislocation C6 to C7: Importance of Adequate Radiolographs  

E-Print Network [OSTI]

soma as well as a fracture dislocation with involvement ofof closed, indirect fractures and dislocations of the lower1–27. 2. Bohlman HH. Acute fractures and dislocations of the

Muñoz-Mahamud, Ernesto; Combalia, Andrés

2011-01-01T23:59:59.000Z

491

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

E-Print Network [OSTI]

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...

Yang, Mei

2011-10-21T23:59:59.000Z

492

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

E-Print Network [OSTI]

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

Li, Yingping

1996-01-01T23:59:59.000Z

493

Degradation of Guar-Based Fracturing Gels: A Study of Oxidative and Enzymatic Breakers  

E-Print Network [OSTI]

Unbroken gel and residue from guar-based fracturing gels can be a cause for formation damage. The effectiveness of a fracturing treatment depends on better achieveing desired fracture geometry, proper proppant placement and after that, a good clean...

Sarwar, Muhammad Usman

2012-02-14T23:59:59.000Z

494

Intrinsic Route to Melt Fracture in Polymer Extrusion: AWeakly Nonlinear Subcritical Instability of Viscoelastic Poiseuille Flow  

E-Print Network [OSTI]

Intrinsic Route to Melt Fracture in Polymer Extrusion: AWeakly Nonlinear Subcritical Instability generic route to melt fracture via a weakly nonlinear subcritical instability of viscoelastic Poiseuille ``subcritical'') instability due to normal stress effects; this instability appears to make melt fracture

van Saarloos, Wim

495

THERMO-HYDRO-MECHANICAL MODELING OF WORKING FLUID INJECTION AND THERMAL ENERGY EXTRACTION IN EGS FRACTURES AND ROCK MATRIX  

SciTech Connect (OSTI)

Development of enhanced geothermal systems (EGS) will require creation of a reservoir of sufficient volume to enable commercial-scale heat transfer from the reservoir rocks to the working fluid. A key assumption associated with reservoir creation/stimulation is that sufficient rock volumes can be hydraulically fractured via both tensile and shear failure, and more importantly by reactivation of naturally existing fractures (by shearing), to create the reservoir. The advancement of EGS greatly depends on our understanding of the dynamics of the intimately coupled rock-fracture-fluid-heat system and our ability to reliably predict how reservoirs behave under stimulation and production. Reliable performance predictions of EGS reservoirs require accurate and robust modeling for strongly coupled thermal-hydrological-mechanical (THM) processes. Conventionally, these types of problems have been solved using operator-splitting methods, usually by coupling a subsurface flow and heat transport simulators with a solid mechanics simulator via input files. An alternative approach is to solve the system of nonlinear partial differential equations that govern multiphase fluid flow, heat transport, and rock mechanics simultaneously, using a fully coupled, fully implicit solution procedure, in which all solution variables (pressure, enthalpy, and rock displacement fields) are solved simultaneously. This paper describes numerical simulations used to investigate the poro- and thermal- elastic effects of working fluid injection and thermal energy extraction on the properties of the fractures and rock matrix of a hypothetical EGS reservoir, using a novel simulation software FALCON (Podgorney et al., 2011), a finite element based simulator solving fully coupled multiphase fluid flow, heat transport, rock deformation, and fracturing using a global implicit approach. Investigations are also conducted on how these poro- and thermal-elastic effects are related to fracture permeability evolution.

Robert Podgorney; Chuan Lu; Hai Huang

2012-01-01T23:59:59.000Z

496

Turbulent flow of gas in fractures  

E-Print Network [OSTI]

sises of 40 - 60, 20 - 40 and 10 - 20 mesh and with varying concentration of proppants . The confining pressure was varied for each core up to $, 000 psi step by step. The proppant concentration in each fracture was varied up to a complete monolayer... an ovex'bux'den pressure of 4, 000 psi, the reduction in flow capaoity would vary from 86 $ to 76 4 with corresponding change of pressure dxop from 2, 000 psi to 7, 000 psi across a 320 ft long fractuxe. ACKHOWLEDGENEN% The author wishes to extend...

Koh, Wong In

1974-01-01T23:59:59.000Z

497

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 Home5b9fcbce19 NoPublicIDAPowerPlantSitingConstruction.pdfNotify98.pdf JumpFlixMapFileFostoria,Chapel,Foyil, Oklahoma:Fracture

498

Nonlinear dynamics in flow through unsaturated fractured-porous media: Status and perspectives  

SciTech Connect (OSTI)

The need has long been recognized to improve predictions of flow and transport in partially saturated heterogeneous soils and fractured rock of the vadose zone for many practical applications, such as remediation of contaminated sites, nuclear waste disposal in geological formations, and climate predictions. Until recently, flow and transport processes in heterogeneous subsurface media with oscillating irregularities were assumed to be random and were not analyzed using methods of nonlinear dynamics. The goals of this paper are to review the theoretical concepts, present the results, and provide perspectives on investigations of flow and transport in unsaturated heterogeneous soils and fractured rock, using the methods of nonlinear dynamics and deterministic chaos. The results of laboratory and field investigations indicate that the nonlinear dynamics of flow and transport processes in unsaturated soils and fractured rocks arise from the dynamic feedback and competition between various nonlinear physical processes along with complex geometry of flow paths. Although direct measurements of variables characterizing the individual flow processes are not technically feasible, their cumulative effect can be characterized by analyzing time series data using the models and methods of nonlinear dynamics and chaos. Identifying flow through soil or rock as a nonlinear dynamical system is important for developing appropriate short- and long-time predictive models, evaluating prediction uncertainty, assessing the spatial distribution of flow characteristics from time series data, and improving chemical transport simulations. Inferring the nature of flow processes through the methods of nonlinear dynamics could become widely used in different areas of the earth sciences.

Faybishenko, Boris

2002-11-27T23:59:59.000Z

499

Prediction and Monitoring Systems of Creep-Fracture Behavior of 9Cr-1Mo Steels for Teactor Pressure Vessels  

SciTech Connect (OSTI)

A recent workshop on next-generation nuclear plant (NGNP) topics underscored the need for research studies on the creep fracture behavior of two materials under consideration for reactor pressure vessel (RPV) applications: 9Cr-1Mo and SA-5XX steels. This research project will provide a fundamental understanding of creep fracture behavior of modified 9Cr-1Mo steel welds for through modeling and experimentation and will recommend a design for an RPV structural health monitoring system. Following are the specific objectives of this research project: • Characterize metallurgical degradation in welded modified 9Cr-1Mo steel resulting from aging processes and creep service conditions. • Perform creep tests and characterize the mechanisms of creep fracture process. • Quantify how the microstructure degradation controls the creep strength of welded steel specimens. • Perform finite element (FE) simulations using polycrystal plasticity to understand how grain texture affects the creep fracture properties of welds. • Develop a microstructure-based creep fracture model to estimate RPVs service life . • Manufacture small, prototypic, cylindrical pressure vessels, subject them to degradation by aging, and measure their leak rates. • Simulate damage evolution in creep specimens by FE analyses. • Develop a model that correlates gas leak rates from welded pressure vessels with the amount of microstructural damage. • Perform large-scale FE simulations with a realistic microstructure to evaluate RPV performance at elevated temperatures and creep strength. • Develop a fracture model for the structural integrity of RPVs subjected to creep loads. • Develop a plan for a non-destructive structural health monitoring technique and damage detection device for RPVs.

Potirniche, Gabriel; Barlow, Fred D.; Charit, Indrajit; Rink, Karl

2013-11-26T23:59:59.000Z

500

Brittle fracture in a periodic structure with internal potential energy. Spontaneous crack propagation  

E-Print Network [OSTI]

Spontaneous brittle fracture is studied based on the recently introduced model (Mishuris and Slepyan, Brittle fracture in a periodic structure with internal potential energy. Proc. Roy. Soc. A, in press). A periodic structure is considered, where only the prospective crack-path layer is specified as a discrete set of alternating initially stretched and compressed bonds. A bridged crack destroying initially stretched bonds may propagate under a certain level of the internal energy without external sources. The general analytical solution with the crack speed $-$ energy relation is presented in terms of the crack-related dynamic Green's function. For the anisotropic two-line chain and lattice considered earlier in quasi-statics, the dynamic problem is examined in detail. The crack speed is found to grow unboundedly as the energy approaches its upper limit. It is revealed that the spontaneous fracture can occur in the form of a pure bridged, partially bridged or fully open crack depending on the internal energy level. Generally, the steady-state mode of the crack propagation is found to be realised, whereas an irregular growth, clustering and the crack speed oscillations are detected in a vicinity of the lower bound of the energy.

Mark Ayzenberg-Stepanenko; Gennady Mishuris; Leonid Slepyan

2014-02-12T23:59:59.000Z