Sample records for natural fracture detection

  1. Naturally fractured tight gas reservoir detection optimization

    SciTech Connect (OSTI)

    NONE

    1999-06-01T23:59:59.000Z

    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.

  2. Naturally fractured tight gas reservoir detection optimization

    SciTech Connect (OSTI)

    NONE

    1996-09-30T23:59:59.000Z

    The focus of this report was on preparing data and modules for Piceance Basin-wide fracture prediction. A review of the geological data input and automated history reconstruction approach was made. Fluid pressure data analysis and preliminary basin simulations were carried out. These activities are summarized briefly below and reviewed in more detail in Appendices A-E. Appendix D is a review of the fluid pressure data and its implications for compartmentation. Preliminary fracture prediction computations on generic basins are presented in Appendix E; these were carried out as part of our code testing activities. The results of these two Appendices are the beginning of what will be the basis of the model testing; fluid pressures are directly comparable with the model predictions and are a key element of fracture nucleation and presentation. We summarize the tectonic and sedimentary history of the Piceance Basin based on our automated history reconstruction and published interpretations. The narrative and figures provide the basic material we have quantified for our CIRF.B basin simulator input. This data supplements our existing well data interpretation approach. It provides an independent check of the automated sedimentary/subsidence history reconstruction module. Fluid pressure data was gathered and analyzed. This data serves two functions. Fluid pressure distribution across the basin provides a quantitative test as it is a direct prediction of CIRF.B. Furthermore, fluid pressure modifies effective stress. It thereby enters fracture nucleation criteria and fracture extension rate and aperture laws. The pressure data is presented in Appendix Din terms of overpressure maps and isosurfaces.

  3. Naturally fractured tight gas reservoir detection optimization. Final report

    SciTech Connect (OSTI)

    NONE

    1997-11-19T23:59:59.000Z

    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.

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

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

    Development of advanced geophysical methods for determining EGS reservoir properties and resource assessment. * Reservoir validation: Detection and imaging of natural and induced...

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

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

    of Enhanced Geothermal Systems Project objectives: Combine geophysical methods for reservoir and fracture characterization with rock physics measurements made under in-situ...

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

    SciTech Connect (OSTI)

    NONE

    1998-04-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    NONE

    1997-12-31T23:59:59.000Z

    Economically viable natural gas production from the low permeability Mesaverde Formation in the Piceance Basin, Colorado requires the presence of an intense set of open natural fractures. Establishing the regional presence and specific location of such natural fractures is the highest priority exploration goal in the Piceance and other western US tight, gas-centered basins. Recently, Advanced Resources International, Inc. (ARI) completed a field program at Rulison Field, Piceance Basin, to test and demonstrate the use of advanced seismic methods to locate and characterize natural fractures. This project began with a comprehensive review of the tectonic history, state of stress and fracture genesis of the basin. A high resolution aeromagnetic survey, interpreted satellite and SLAR imagery, and 400 line miles of 2-D seismic provided the foundation for the structural interpretation. The central feature of the program was the 4.5 square mile multi-azimuth 3-D seismic P-wave survey to locate natural fracture anomalies. The interpreted seismic attributes are being tested against a control data set of 27 wells. Additional wells are currently being drilled at Rulison, on close 40 acre spacings, to establish the productivity from the seismically observed fracture anomalies. A similar regional prospecting and seismic program is being considered for another part of the basin. The preliminary results indicate that detailed mapping of fault geometries and use of azimuthally defined seismic attributes exhibit close correlation with high productivity gas wells. The performance of the ten new wells, being drilled in the seismic grid in late 1996 and early 1997, will help demonstrate the reliability of this natural fracture detection and mapping technology.

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

    SciTech Connect (OSTI)

    NONE

    1994-10-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Xue, Wenxu

    2011-02-22T23:59:59.000Z

    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...

  10. Naturally fractured tight gas reservoir detection optimization. Quarterly report, January--March 1995

    SciTech Connect (OSTI)

    NONE

    1995-05-01T23:59:59.000Z

    This report describes progress in the following five projects: (1) Geologic assessment of the Piceance Basin; (2) Regional stratigraphic studies, Upper Cretaceous Mesaverde Group, southern Piceance Basin, Colorado; (3) Structurally controlled and aligned tight gas reservoir compartmentalization in the San Juan and Piceance Basins--Foundation for a new approach to exploration and resource assessments of continuous type deposits; (4) Delineation of Piceance Basin basement structures using multiple source data--Implications for fractured reservoir exploration; and (5) Gas and water-saturated conditions in the Piceance Basin, western Colorado--Implications for fractured reservoir detection in a gas-centered coal basin.

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

    E-Print Network [OSTI]

    Sesetty, Varahanaresh

    2012-10-19T23:59:59.000Z

    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...

  12. 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.

  13. RATE DECLINE ANALYSIS FOR NATURALLY FRACTURED RESERVOIRS

    E-Print Network [OSTI]

    Stanford University

    RATE DECLINE ANALYSIS FOR NATURALLY FRACTURED RESERVOIRS A REPORT SUBMITTED TO THE DEPARTMENT analylsiis for constant pressure production in a naturally fractured reservoir is presented. The solution, the Warren and Root model which assumes fracturing is perfectly unifom, provides an upper bound of reservoir

  14. Characterization of natural fractures in Mesaverde core from the multiwell experiment

    SciTech Connect (OSTI)

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

    1988-09-01T23:59:59.000Z

    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.

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

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

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

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

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

    7 4.4.1 Detecting Fractures Using Technology at High Temperatures and Depths - Geothermal Ultrasonic Fracture Imager (GUFI) Presentation Number: 015 Investigator: Patterson, Doug...

  17. Estimating Major and Minor Natural Fracture Patterns in Gas

    E-Print Network [OSTI]

    Mohaghegh, Shahab

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

  18. A triple-continuum pressure-transient model for a naturally fractured vuggy reservoir

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    simulation of naturally fractured reservoirs, Water Resour.model for fissured fractured reservoir, Soc. Pet. Eng. J. ,behavior of naturally fractured reservoirs, Soc. Pet. Eng.

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

    E-Print Network [OSTI]

    Geiger, S.

    2012-01-01T23:59:59.000Z

    behavior of naturally fractured reservoirs. SPE Journal, R.the Bristol Channel fractured reservoir analogue (a), ?uidfor naturally fractured reservoirs. These simulations are

  20. MODELING OF NATURALLY FRACTURED RESERVOIRS BY FORMAL HOMOGENIZATION TECHNIQUES*

    E-Print Network [OSTI]

    Douglas Jr., Jim

    MODELING OF NATURALLY FRACTURED RESERVOIRS BY FORMAL HOMOGENIZATION TECHNIQUES* Todd Arbogast,y Jim in naturally fractured reservoirs. A single component in a single phase and two-component mis- cible. porous medium, double porosity, fractured reservoir, homogenization. yDepartment of Mathematics, Purdue

  1. 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

  2. ESTIMATION OF MATRIX BLOCK SIZE DISTRIBUTION IN NATURALLY FRACTURED RESERVOIRS

    E-Print Network [OSTI]

    Stanford University

    ESTIMATION OF MATRIX BLOCK SIZE DISTRIBUTION IN NATURALLY FRACTURED RESERVOIRS A Report Submitted;2 ABSTRACT Interporosity flow in a naturslly fractured reservoir is modelled by a new formulation of the distribution. Thus, observed pressure response from fractured reservoirs can be analysed to obtain the matrix

  3. I N F I N I T E CONDUCTIVITY FRACTURE NATURALLY FRACTURED RESERVOIR

    E-Print Network [OSTI]

    Stanford University

    I N F I N I T E CONDUCTIVITY FRACTURE I N A NATURALLY FRACTURED RESERVOIR A REPORT SUBMITTED How& #12;ABSTRACT This r e p o r t describes t h e behavior of a n a t u r a l l y fractured r e s e r v o i r when a well is producing a t constant rate through an i n f i n i t e conductivity fracture

  4. Simulation of naturally fractured reservoirs using empirical transfer function

    E-Print Network [OSTI]

    Tellapaneni, Prasanna Kumar

    2004-09-30T23:59:59.000Z

    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...

  5. The imbibition process of waterflooding in naturally fractured reservoirs

    E-Print Network [OSTI]

    Huapaya Lopez, Christian A.

    2005-02-17T23:59:59.000Z

    and validate it with laboratory experiments in the literature; (2) study the effect of countercurrent imbibition in field scale applications; and (3) develop procedures for using the dual-porosity to simulate fluid displacement in a naturally fractured...

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

    E-Print Network [OSTI]

    Al Harbi, Mishal H.

    2005-08-29T23:59:59.000Z

    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...

  7. 3-D description of fracture surfaces and stress-sensitivity analysis for naturally fractured reservoirs

    SciTech Connect (OSTI)

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

    1997-08-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Douglas Jr., Jim

    A Parallelizable Method for Two-Phase Flows in Naturally-Fractured Reservoirs Jim Douglas, Jr. #3 is proposed for the study of naturally- fractured reservoir systems. It has proved to be computationally e- ooding a naturally-fractured petroleum reservoir or to unsaturated groundwater ow again in a naturally-fractured

  9. A triple-continuum pressure-transient model for a naturally fractured vuggy reservoir

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    well test data from a fractured-vuggy reservoir in Westernwell test data from a fractured-vuggy reservoir in Westerndata for two wells from a naturally fractured vuggy oil reservoir,

  10. Natural time analysis of critical phenomena: The case of pre-fracture electromagnetic emissions

    SciTech Connect (OSTI)

    Potirakis, S. M. [Department of Electronics, Technological Education Institute (TEI) of Piraeus, 250 Thivon and P. Ralli, Aigaleo, Athens GR-12244 (Greece)] [Department of Electronics, Technological Education Institute (TEI) of Piraeus, 250 Thivon and P. Ralli, Aigaleo, Athens GR-12244 (Greece); Karadimitrakis, A. [Department of Physics, Section of Electronics, Computers, Telecommunications and Control, University of Athens, Panepistimiopolis, Zografos, Athens GR-15784 (Greece)] [Department of Physics, Section of Electronics, Computers, Telecommunications and Control, University of Athens, Panepistimiopolis, Zografos, Athens GR-15784 (Greece); Eftaxias, K. [Department of Physics, Section of Solid State Physics, University of Athens, Panepistimiopolis, Zografos, Athens GR-15784 (Greece)] [Department of Physics, Section of Solid State Physics, University of Athens, Panepistimiopolis, Zografos, Athens GR-15784 (Greece)

    2013-06-15T23:59:59.000Z

    Criticality of complex systems reveals itself in various ways. One way to monitor a system at critical state is to analyze its observable manifestations using the recently introduced method of natural time. Pre-fracture electromagnetic (EM) emissions, in agreement to laboratory experiments, have been consistently detected in the MHz band prior to significant earthquakes. It has been proposed that these emissions stem from the fracture of the heterogeneous materials surrounding the strong entities (asperities) distributed along the fault, preventing the relative slipping. It has also been proposed that the fracture of heterogeneous material could be described in analogy to the critical phase transitions in statistical physics. In this work, the natural time analysis is for the first time applied to the pre-fracture MHz EM signals revealing their critical nature. Seismicity and pre-fracture EM emissions should be two sides of the same coin concerning the earthquake generation process. Therefore, we also examine the corresponding foreshock seismic activity, as another manifestation of the same complex system at critical state. We conclude that the foreshock seismicity data present criticality features as well.

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

    E-Print Network [OSTI]

    Arbogast, Todd

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

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

    SciTech Connect (OSTI)

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

    1997-08-01T23:59:59.000Z

    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.

  13. STRUCTURE OF THE LOW PERMEABLE NATURALLY FRACTURED GEOTHERMAL RESERVOIR Chrystel Dezayes*, Albert Genter** & Benot Valley ***

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 STRUCTURE OF THE LOW PERMEABLE NATURALLY FRACTURED GEOTHERMAL RESERVOIR AT SOULTZ Chrystel cluster appears as a fractured reservoir developed within a low permeable matrix. Fracture zones represent) where reservoir development involved the reactivation of the pre- existing fractures in the granite [16

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

    E-Print Network [OSTI]

    Stanford University

    THE ROLE OF CAPILLARY FORCES IN THE NATURAL STATE OF FRACTURED GEOTHERMAL RESERVOIRS A REPORT model is adequate in describing the natural state of a fractured geothermal reservoir. Because of this a fractured geothermal reservoir. The numerical simulations were carried to steady state with the use

  15. Analysis of P-wave seismic response for fracture detection: modelling and case studies 

    E-Print Network [OSTI]

    Xu, Yungui

    2012-06-25T23:59:59.000Z

    This thesis addresses a few specific issues in the use of wide azimuth P-wave seismic data for fracture detection based on numerical modelling and real data. These issues include the seismic response of discrete fractures, ...

  16. 3.3 NUMERICAL MODELING OF SOLID DEFORMATION AND STRESS-DEPENDENT PERMEABILITY IN NATURALLY FRACTURED

    E-Print Network [OSTI]

    Schechter, David S.

    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

  17. A Numerical Algorithm for Fluid Flow in 3D Naturally Fractured Porous Media

    E-Print Network [OSTI]

    Kentucky, University of

    . Such fractured reservoirs could be modeled by permitting the porosity and permeability to vary rapidly as if the reservoir has two porous structures, one for the fractures and the other for the matrix blocksA Numerical Algorithm for Fluid Flow in 3D Naturally Fractured Porous Media Seongjai Kim Abstract

  18. A Handbook for the Application of Seismic Methods for Quantifying Naturally Fractured Gas Reservoirs in the San Juan Basin, New Mexico

    E-Print Network [OSTI]

    2004-01-01T23:59:59.000Z

    resource in naturally fractured reservoirs? At the beginningheterogeneous and fractured reservoirs, such as the San JuanP-wave velocity when a fractured reservoir is present, can

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

    E-Print Network [OSTI]

    Kim, Tae Hyung

    2009-05-15T23:59:59.000Z

    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...

  20. Development of Reservoir Characterization Techniques and Production Models for Exploiting Naturally Fractured Reservoirs

    SciTech Connect (OSTI)

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

    2002-10-08T23:59:59.000Z

    During this reporting period, research was continued on characterizing and modeling the behavior of naturally fractured reservoir systems. This report proposed a model to relate the seismic response to production data to determine crack spacing and aperture, provided details of tests of proposed models to obtain fracture properties from conventional well logs with actual field data, and verification of the naturally fractured reservoir simulator developed in this project.

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

    SciTech Connect (OSTI)

    David S. Schechter

    2005-04-27T23:59:59.000Z

    This report describes the work performed during the fourth 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 artificially fractured cores (AFCs) and X-ray CT scanner to examine the physical mechanisms of bypassing in hydraulically fractured reservoirs (HFR) and naturally fractured reservoirs (NFR) that eventually result in more efficient CO{sub 2} flooding in heterogeneous or fracture-dominated reservoirs. In Chapter 1, we worked with DOE-RMOTC to investigate fracture properties in the Tensleep Formation at Teapot Dome Naval Reserve as part of their CO{sub 2} sequestration project. In Chapter 2, we continue our investigation to determine the primary oil recovery mechanism in a short vertically fractured core. Finally in Chapter 3, we report our numerical modeling efforts to develop compositional simulator with irregular grid blocks.

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

    SciTech Connect (OSTI)

    R. L. Billingsley; V. Kuuskraa

    2006-03-31T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2002-12-31T23:59:59.000Z

    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.

  4. 3 RESERVOIR PERFORMANCE ANALYSIS 3.1 ANALYSIS OF IMBIBITION MECHANISM IN THE NATURALLY FRACTURED

    E-Print Network [OSTI]

    Schechter, David S.

    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

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

    E-Print Network [OSTI]

    Angel Restrepo, Juan Alejandro

    2000-01-01T23:59:59.000Z

    . The objectives of this work are as follows: First, we generated new type curves for the analysis of pressure drawdown and buildup tests performed in naturally fractured reservoirs. Next, we develop a systematic approach for the analysis and interpretation...

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

    E-Print Network [OSTI]

    Angel Restrepo, Juan Alejandro

    2000-01-01T23:59:59.000Z

    This work introduces new type curve solutions for an unfractured well in an infinite-acting naturally fractured reservoir, including wellbore storage and skin effects. Both pseudosteady-state¹ and transient²?³ interporosity flow models are studied...

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

    E-Print Network [OSTI]

    Schechter, David S.

    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

  8. A Multiple-Porosity Model for A Single-Phase Flow Through Naturally-Fractured Porous Media

    E-Print Network [OSTI]

    Douglas Jr., Jim

    compressible uid in a multiscale, naturally-fractured reservoir is presented. The problem can serve as a modelA Multiple-Porosity Model for A Single-Phase Flow Through Naturally-Fractured Porous Media Jim counterpart. Further, a model for the (N + 1)-scale problem in a fractured medium is derived. The well

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

    E-Print Network [OSTI]

    Jamili, Ahmad

    2010-04-22T23:59:59.000Z

    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...

  10. Integrated seismic study of naturally fractured tight gas reservoirs

    SciTech Connect (OSTI)

    Mavko, G.M.; Nur, A.

    1993-12-31T23:59:59.000Z

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

  11. Azimuthal Offset-Dependent Attributes (AVO And FVO) Applied To Fracture Detection

    E-Print Network [OSTI]

    Shen, Feng

    1999-01-01T23:59:59.000Z

    Using the amplitude versus offset (AVO) and the frequency versus offset (FVO) information, the diagnostic ability of P-wave seismic data in fracture detection is investigated. The offset-dependent attributes (AVO and FVO) ...

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

    SciTech Connect (OSTI)

    David S. Schechter

    2003-10-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    David S. Schechter

    2004-04-26T23:59:59.000Z

    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.

  14. Neural network technology for automatic fracture detection in sonic borehole image data

    E-Print Network [OSTI]

    Schnorrenberg, Frank Theo

    1992-01-01T23:59:59.000Z

    NEURAL NETWORK TECHNOLOGY FOR AUTOMATIC FRACTURE DETECTION IN SONIC BOREHOLE IMAGE DATA A Thesis by FRANK THEO SCHNORRENBERG Submitted to the Office of Graduate Studies of Texas A&M University tn partial fulfillment of the requirements... for the degree of MASTER OF SC1ENCE December 1992 Major Subject: Computer Science NEURAL NETWORK TECHNOLOGY FOR AUTOMATIC FRACTURE DETECTION IN SONIC BOREHOLE IMAGE DATA A Thesis by FRANK THEO SCHNORRENBERG Subnutted to the Office of Graduate Studies...

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

    E-Print Network [OSTI]

    Fineout, James Mark

    1992-01-01T23:59:59.000Z

    , they developed both a single matrix block model and a dual matrix block model with variable fracture width. These tests related imbibition theory with regard to matrix block size, permeability and fluid viscosity affects on oil recovery. They also determined... in naturally fractured reservoirs have relied upon material balance calculations to determine saturation changes. Through the use of Computed Tomography scanning, we have developed a technique not only to determine saturation changes but also positional...

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

    E-Print Network [OSTI]

    Tao, Qingfeng

    2010-07-14T23:59:59.000Z

    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...

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

    SciTech Connect (OSTI)

    David S. Schechter

    2004-10-10T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2004-05-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    1996-08-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2008-09-30T23:59:59.000Z

    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.

  1. OVERBURDEN PRESSURE AFFECTS FRACTURE APERTURE

    E-Print Network [OSTI]

    Schechter, David S.

    OVERBURDEN PRESSURE AFFECTS FRACTURE APERTURE AND FRACTURE PERMEABILITY IN A FRACTURED RESERVOIR are in integrated reservoir study, reservoir charac- terization, naturally fractured reservoirs, waterflooding in Hydraulically and Naturally Fractured Reservoirs." His research areas include experimental analysis

  2. 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 DataDepartment of Energy Your Density Isn't Your Destiny:Revised Finding of No53197E T A * S H I E LGeothermal Ultrasonic Fracture Imager

  3. Development of Reservoir Characterization Techniques and Production Models for Exploiting Naturally Fractured Reservoirs

    SciTech Connect (OSTI)

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

    2003-02-11T23:59:59.000Z

    This research was directed toward developing a systematic reservoir characterization methodology which can be used by the petroleum industry to implement infill drilling programs and/or enhanced oil recovery projects in naturally fractured reservoir systems in an environmentally safe and cost effective manner. It was anticipated that the results of this research program will provide geoscientists and engineers with a systematic procedure for properly characterizing a fractured reservoir system and a reservoir/horizontal wellbore simulator model which can be used to select well locations and an effective EOR process to optimize the recovery of the oil and gas reserves from such complex reservoir systems.

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

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

    made excellent progress on key reservoir characterization that can be accomplished by seismic tomography. Petrophysical property measurements are highly relevant for converting...

  5. Detection and Characterization of Natural and Induced Fractures for the

    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 DataDepartment of Energy Your Density Isn't Your Destiny:Revised Finding of No53197E T A * S H I E LGeothermal Ultrasonic

  6. 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.

  7. Simulation Study to Investigate the Effect of Natural Fractures on the Performance of Surfactant-Polymer Flood in Carbonate Reservoirs 

    E-Print Network [OSTI]

    Sayedakram, Nawaf Ibrahim A

    2011-10-21T23:59:59.000Z

    (Salehi 5 - 1? BN (>5) is -current of , 1999). -surfactant , 2009). 6 2. RESEARCH OBJECTIVES The main objective of this research is to study the effect of natural fractures on surfactant polymer flood (SPF... SIMULATION STUDY TO INVESTIGATE THE EFFECT OF NATURAL FRACTURES ON THE PERFORMANCE OF SURFACTANT-POLYMER FLOOD IN CARBONATE RESERVOIRS A Thesis by NAWAF IBRAHIM A. SAYEDAKRAM Submitted to the Office of Graduate Studies of Texas A...

  8. Modeling Wettability Alteration using Chemical EOR Processes in Naturally Fractured Reservoirs

    SciTech Connect (OSTI)

    Mojdeh Delshad; Gary A. Pope; Kamy Sepehrnoori

    2007-09-30T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Fang, Xinding

    2011-01-01T23:59:59.000Z

    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 ...

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

    SciTech Connect (OSTI)

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

    1982-11-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Texas at Austin, University of

    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

  12. Fracture-Flow-Enhanced Solute Diffusion into Fractured Rock

    E-Print Network [OSTI]

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

    2008-01-01T23:59:59.000Z

    of Naturally Fractured Reservoirs, Society of Petroleumresources from fractured reservoirs (e.g. , Warren and Root,Reservoir Engineering Stanford University, Stanford, California, January 28-30, 2008 SGP-TR-185 FRACTURE-FLOW-ENHANCED SOLUTE DIFFUSION INTO FRACTURED

  13. A physically based numerical approach for modeling fracture-matrix interaction in fractured reservoirs

    E-Print Network [OSTI]

    Wu, Yu-Shu; Pruess, Karsten

    2004-01-01T23:59:59.000Z

    of naturally fractured reservoirs with uniform fracturefor naturally fractured reservoirs, SPE-11688, Presented atflow simulations in fractured reservoirs, Report LBL- 15227,

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

    E-Print Network [OSTI]

    Pruess, K.

    2010-01-01T23:59:59.000Z

    Flow in Naturally Fractured Reservoirs, Society of Petroleumfor Naturally Fractured Reservoirs, paper SPE-11688,Determining Naturally Fractured Reservoir Properties by Well

  15. Analysis of flow behavior in fractured lithophysal reservoirs

    E-Print Network [OSTI]

    Liu, Jianchun; Bodvarsson, G.S.; Wu, Yu-Shu

    2002-01-01T23:59:59.000Z

    R. , 1980. Naturally Fractured Reservoirs, Petroleum, Tulsa,bounded naturally fractured reservoirs. Soc. Pet. Eng. J.test in a naturally fractured reservoir. J. Pet. Tech. 1295–

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

    E-Print Network [OSTI]

    Fan, Jin

    1993-01-01T23:59:59.000Z

    pseudopressures for fracture permeabilities of I, 10, 100, and 1000 md are plotted versus time, with other parameters being constant. Fig, 6. 3 shows that as fracture permeability increases, the convergence time decreases because the rate of gas flow from...

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

    E-Print Network [OSTI]

    Schechter, David S.

    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

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

    E-Print Network [OSTI]

    Schechter, David S.

    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

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

    E-Print Network [OSTI]

    Fineout, James Mark

    1992-01-01T23:59:59.000Z

    producing zones in the Austin Chalk. . . 3. 3 Spraberry production potential due to fracture distribution and orientation . 27 3. 4 Florence field, Colorado with oil contained in fractures only. . . 3. S Niobrara stratagraphic diagram. . 29 Figure Page.... . Florence Field. . . 26 26 Niobrara Trend . . IV FRACTURED RESERVOIR IMBIBITION EXPERIMENTS . . . . . . . . 30 Experimental Method 30 CT Porosity Calculation. 31 CT Oil Saturations 31 CT Image Resolution. Experimental Sequence. . 34 Determining...

  20. INNOVATIVE METHODOLOGY FOR DETECTION OF FRACTURE-CONTROLLED SWEET SPOTS IN THE NORTHERN APPALACHIAN BASIN

    SciTech Connect (OSTI)

    Robert Jacobi; John Fountain

    2002-01-30T23:59:59.000Z

    In the structure task, we completed reducing the data we had collected from a N-S transect on the east of Seneca Lake. We have calculated the fracture frequency for all the fracture sets at each site, and constructed modified rose diagrams that summarize the fracture attributes at each site. These data indicate a N-striking fault near the southeastern shore of Seneca Lake, and also indicate NE and ENE-trending FIDs and faults north of Valois. The orientation and existence of the ENE-striking FIDs and faults are thought to be guided by faults in the Precambrian basement; these basement faults apparently were sufficiently reactivated to cause faulting in the Paleozoic section. Other faults are thrust ramps above the Silurian salt section that were controlled by a far-field Alleghanian stress field. 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 is insufficient to definitively identify faults. However, relatively sharp elevational changes east of Keuka Lake support the contention that faults occur along the east side of Keuka Lake. Outcrop stratigraphy along the east side of Seneca Lake indicates that faults and gentle folds can be inferred from the some exposures along Seneca Lake, but the lensing nature of the individual sandstones can preclude long-distance definitive correlations and structure identification. Soil gas data collected during the 2000 field season was reduced and displayed in the previous semiannual report. The seismic data that Quest licensed has been reprocessed. Several grabens observed in the Trenton reflector are consistent with surface structure, soil gas, and aeromagnetic anomalies. In this report we display an interpreted seismic line that crosses the Glodes Corners and Muck Farm fields. The final report from the subcontractor concerning the completed aeromagnetic survey is included. Prominent magnetic anomalies suggest that faults in the Precambrian basement are located beneath regions where grabens in the Trenton are located. The trend and location of these faults based on aeromagnetics agrees with the location based on FIDs. These data indicate that integration of aeromagnetic and topographic lineaments, surface structure, soil gas with seismic and well logs allows us to extrapolate Trenton-Black River trends away from confirmatory seismic lines.

  1. Advanced Reservoir Characterization and Evaluation of C02 Gravity Drainage in the Naturally Fractured Sprayberry Trend Area

    SciTech Connect (OSTI)

    David S. Schechter

    1998-04-30T23:59:59.000Z

    The objective is to assess the economic feasibility of CO2 flooding of the naturally fractured Straberry Trend Area in west Texas. Research is being conducted in the extensive characterization of the reservoirs, the experimental studies of crude oil/brine/rock (COBR) interaction in the reservoirs, the analytical and numerical simulation of Spraberry reservoirs, and the experimental investigations on CO2 gravity drainage in Spraberry whole cores.

  2. Multiscale Methods for Modeling Fluid Flow Through Naturally Fractured Carbonate Karst P. Popov, G. Qin, L. Bi, Y. Efendiev, R. Ewing, Institute for Scientific Computation, Texas A&M University; Z. Kang, J. Li,

    E-Print Network [OSTI]

    Ewing, Richard E.

    reservoir conditions, such as partially filled fractures. Introduction Naturally fractured karst reservoirsSPE 110778 Multiscale Methods for Modeling Fluid Flow Through Naturally Fractured Carbonate Karst Reservoirs P. Popov, G. Qin, L. Bi, Y. Efendiev, R. Ewing, Institute for Scientific Computation, Texas A

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

    E-Print Network [OSTI]

    Kilicaslan, Ufuk

    2013-12-03T23:59:59.000Z

    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...

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

    SciTech Connect (OSTI)

    Schechter, David S.; Vance, Harold

    2003-03-10T23:59:59.000Z

    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.

  5. Brief Guide to the MINC-Method for Modeling Flow and Transport in Fractured Media

    E-Print Network [OSTI]

    Pruess editor, K.

    2010-01-01T23:59:59.000Z

    Simulating Naturally Fractured Reservoirs Using a SubdomainModels of Naturally Fractured Reservoirs, In Situ, 15, (2),for Naturally Fractured Reservoirs, papr,r SPE-11688,

  6. Aligned vertical fractures, HTI reservoir symmetry, and Thomsen seismic anisotropy parameters

    E-Print Network [OSTI]

    Berryman, James G.

    2008-01-01T23:59:59.000Z

    seismic parameters for fractured reservoirs when the crackin a naturally fractured gas reservoir, The Leading Edge,

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

    SciTech Connect (OSTI)

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

    2007-03-31T23:59:59.000Z

    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

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

    SciTech Connect (OSTI)

    Schechter, D.S.

    1999-02-03T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Knight, Bill; Schechter, David S.

    2002-07-26T23:59:59.000Z

    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.

  10. Detection of the Natural Alpha Decay of Tungsten

    E-Print Network [OSTI]

    C. Cozzini; G. Angloher; C. Bucci; F. von Feilitzsch; D. Hauff; S. Henry; Th. Jagemann; J. Jochum; H. Kraus; B. Majorovits; V. Mikhailik; J. Ninkovic; F. Petricca; W. Potzel; F. Proebst; Y. Ramachers; W. Rau; M. Razeti; W. Seidel; M. Stark; L. Stodolsky; A. J. B. Tolhurst; W. Westphal; H. Wulandari

    2004-10-26T23:59:59.000Z

    The natural alpha decay of 180W has been unambiguously detected for the first time. The alpha peak is found in a (gamma,beta and neutron)-free background spectrum. This has been achieved by the simultaneous measurement of phonon and light signals with the CRESST cryogenic detectors. A half-life of T1/2 = (1.8 +- 0.2) x 10^18 y and an energy release of Q = (2516.4 +- 1.1 (stat.) +- 1.2 (sys.)) keV have been measured. New limits are also set on the half-lives of the other naturally occurring tungsten isotopes.

  11. Integrated seismic study of naturally fractured tight gas reservoirs. Final report, September 1991--January 1995

    SciTech Connect (OSTI)

    Mavko, G.; Nur, A.

    1995-01-01T23:59:59.000Z

    The approach in this project has been to integrate the principles of rock physics into a quantitative processing and interpretation scheme that exploits, where possible, the broader spectrum of fracture zone signatures: (1) anomalous compressional and shear wave velocity; (2) Q and velocity dispersion; (3) increased velocity anisotropy; (4) amplitude vs. offset (AVO) response, and (5) variations in frequency content. As part of this the authors have attempted to refine some of the theoretical rock physics tools that should be applied in any field study to link the observed seismic signatures to the physical/geologic description of the fractured rock. The project had 3 key elements: (1) rock physics studies of the anisotropic viscoelastic signatures of fractured rocks, (2) acquisition and processing of seismic reflection field data, and (3) interpretation of seismic and well log data. The study site is in a producing field operated by Amoco and Arco at the southern boundary of the Powder River basin in Wyoming. During the winter of 1992--1993 the authors collected about 50 km of 9-component reflection seismic data and obtained existing log data from several wells in the vicinity. The paper gives background information on laboratory studies, seismic field studies of fracture anisotropy, and the problem of upscaling from the laboratory to the field. It discusses fluid effects on seismic anisotropy and a method for predicting stress-induced seismic anisotropy. Then results from the field experiment are presented and discussed: regional geologic framework and site description; seismic data acquisition; shear wave data and validation; and P-wave data analysis. 106 refs., 52 figs.

  12. Flashback Detection Sensor for Hydrogen Augmented Natural Gas Combustion

    SciTech Connect (OSTI)

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

    2007-05-01T23:59:59.000Z

    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.

  13. Fracture prediction in metal sheets

    E-Print Network [OSTI]

    Lee, Young-Woong

    2005-01-01T23:59:59.000Z

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

  14. Use of fracture surface features to improve core description and fracture interpretation in Niobrara and Gallup formations, Colorado and New Mexico

    SciTech Connect (OSTI)

    Ward, B.J.; Petrusak, R.L.; Kulander, B.R. (Amoco Production Co. Research, Tulsa, OK (USA))

    1989-09-01T23:59:59.000Z

    The Niobrara formation in the Denver basin and the Gallup formation in the eastern San Juan Basin are very fine-grained, low-permeability reservoirs. Natural fracturing provides essential reservoir permeability. When natural and induced fractures are correctly identified in core, understanding of key fractured reservoir characteristics such as fracture spacing, fracture intensity, and fracture size improves greatly. For example, the Gallup has a significant amount of non-mineralized natural fractures which are generally difficult to identify in core as natural. If these fractures are misidentified as induced, fracture intensity may be underestimated and fracture spacing may be overestimated. Diagnostic fracture surface features are very well developed in the Gallup and Niobrara. Proper identification of induced fractures and nonmineralized natural fractures is done by examining these fracture surface features under oblique illumination. The Niobrara cores that were examined provide excellent examples of induced fractures. These cores have predominately mineral-filled and slickened natural fractures. Fracture surface features on the non-mineralized fractures positively identify these fractures as induced and demonstrate that nonmineralized natural fractures are a minor component of the reservoir. The Gallup cores provide excellent examples of the diagnostic surface features of natural fractures. Fractured intervals up to 20 ft long have been recovered in Gallup core. Multiple individual fractures which comprise the larger fractured intervals are identified using fracture surface morphology. This type of detailed fracture description improves evaluations of fractured reservoir quality in the Gallup formation.

  15. INNOVATIVE METHODOLOGY FOR DETECTION OF FRACTURE-CONTROLLED SWEET SPOTS IN THE NORTHERN APPALACHIAN BASIN

    SciTech Connect (OSTI)

    Robert Jacobi; John Fountain

    2001-02-28T23:59:59.000Z

    In the structure task, we completed a N-S transect east of Seneca Lake that indicated a N-striking fault near the southeastern shore of Seneca Lake, and also indicated NE and ENE-trending FIDs and faults north of Valois. The orientation and existence of the NE-striking FIDs and faults are thought to be controlled by basement faults, rather than thrust ramps above the Salina salt controlled only by a far-field Alleghanian stress field. Structure contour maps based on well log analyses have been constructed but not interpreted. Soil gas data displayed a number of ethane-charged soil gas ''spikes'' on a N-S transect from Ovid south to near Valois. The soil gas team found a larger number of spikes in the northern half of the survey, suggesting more open fractures (and faults) in the northern half of the survey. Seismic data has been purchased and reprocessed. Several grabens observed in the Trenton reflector are consistent with surface structure, soil gas, and aeromagnetic anomalies. The aeromagnetic survey is completed and the data is processed. Prominent magnetic anomalies suggest that faults in the Precambrian basement are located beneath regions where grabens in the Trenton are located.

  16. 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)

    Schechter, D.S.

    1998-07-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Mhiri, Adnene

    2014-08-10T23:59:59.000Z

    : ? Uniform distribution of heterogeneities that cause a variation of geomechanical properties such as: — In-situ stress — Fracture initiation pressure — Elastic moduli (Shear modulus and Poisson’s ratio) ? No interaction with natural fractures: — Natural... that are dynamically created due to the change in the geomechanical properties in the vicinity of the primary fracture these are referred to as secondary fractures and are thought to be orthogonal to primary fractures. ? The fractures that originate due...

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

    E-Print Network [OSTI]

    Wang, J.S.Y.

    2013-01-01T23:59:59.000Z

    flow in naturally fractured reservoirs: Proceedings, 2ndliquid-dominated, fractured reservoir over a twenty- yeardrawdown. (c) Fractured Reservoir: The double-porosity

  19. Naturally fractured tight gas reservoir detection optimization. Quarterly report, July 1 - September 30, 1995

    SciTech Connect (OSTI)

    NONE

    1995-12-31T23:59:59.000Z

    This report describes progress in the following tasks: high-resolution aeromagnetic survey of the southern Piceance Basin of western Colorado; field performance site selection of Rulison Field for seismic acquisition which covers technical work to be performed; seismic acquisition processing and associated costs;theoretical background concerning P-wave multi-azimuth 3D seismic; field data examples of P-wave multi-azimuth data; and 3D basin modeling.

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

    SciTech Connect (OSTI)

    NONE

    1995-07-31T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Patzek, Tadeusz W.

    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

  2. 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)

    Schechter, D.

    1996-07-01T23:59:59.000Z

    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.

  3. Integrated seismic study of naturally fractured tight gas reservoirs. Technical progress report, April 1, 1993--June 31, 1993

    SciTech Connect (OSTI)

    Mavko, G.; Nur, A.

    1993-07-26T23:59:59.000Z

    This was the seventh quarter of the contract. During this quarter we (1) continued the large task of processing the seismic data, (2) collected additional geological information to aid in the interpretation, (3) tied the well log data to the seismic via generation of synthetic seismograms, (4) began integrating regional structural information and fracture trends with our observations of structure in the study area, (5) began constructing a velocity model for time-to-depth conversion and subsequent AVO and raytrace modeling experiments, and (6) completed formulation of some theoretical tools for relating fracture density to observed elastic anisotropy. The study area is located at the southern end of the Powder River Basin in Converse County in east-central Wyoming. It is a low permeability fractured site, with both gas and oil present. Reservoirs are highly compartmentalized due to the low permeabilities, and fractures provide the only practical drainage paths for production. The two formations of interest are: The Niobrara: a fractured shale and limey shale to chalk, which is a reservoir rock, but also its own source rock. The Frontier: a tight sandstone lying directly below the Niobrara, brought into contact with it by an unconformity. A basemap is presented with the seismic lines being analyzed for this project plus locations of 13 wells that we are using to supplement the analysis. The arrows point to two wells for which we have constructed synthetic seismograms.

  4. active fracture model: Topics by E-print Network

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

    porosity of naturally fractured reservoirs with no matrix porosity using stochastic fractal models Texas A&M University - TxSpace Summary: Determining fracture characteristics...

  5. Integrated seismic study of naturally fractured tight gas reservoirs. Technical progress report, October 1, 1993--December 31, 1993

    SciTech Connect (OSTI)

    Mavko, G.; Nur, A.

    1994-01-29T23:59:59.000Z

    This was the ninth quarter of the contract. During this quarter we (1) continued processing the seismic data, (2) collected additional logs to aid in the interpretation, and (3)began modeling some of the P-wave amplitude anomalies that we see in the data. The study area is located at the southern end of the powder river Basin in Converse county in east-central Wyoming. It is a low permeability fractured site, with both has and oil present. Reservoirs are highly compartmentalized due tot he low permeabilities, and fractures provide the only practical drainage paths for production. The two formations of interest are: The Niobrara; a fractured shale and limey shale to chalk, which is a reservoir rock, but also its own source rock. The Frontier, a tight sandstone lying directly below the Niobrara, brought into contract with it by an unconformity.

  6. Integrated seismic study of naturally fractured tight gas reservoirs. Technical progress report, January 1, 1994--March 31, 1994

    SciTech Connect (OSTI)

    Mavko, G.; Nur, A.

    1994-04-29T23:59:59.000Z

    The study area is located at the southern end of the Powder River Basin in Converse County in east-central Wyoming. It is a low permeability fractured site, with both gas and oil present. Reservoirs are highly compartmentalized due to the low permeabilities, and fractures provide the only practical drainage paths for production. The two formations of interest are: The Niobrara, a fractured shale and limey shale to chalk, which is a reservoir rock, but also its own source rock; and the Frontier, a tight sandstone lying directly below the Niobrara, brought into contact with it by an unconformity. This was the tenth quarter of the contract. During this quarter the investigators (1) continued processing the seismic data, and (2) continued modeling some of the P-wave amplitude anomalies that we see in the data.

  7. Numerical simulation of single-phase and multiphase non-Darcy flow in porous and fractured reservoirs

    E-Print Network [OSTI]

    Wu, Yu-Shu

    2000-01-01T23:59:59.000Z

    flow simulations in fractured reservoirs, Report LBL-15227,behavior of naturally fractured reservoirs, Soc. Pet. Eng.Flow in Porous and Fractured Reservoirs Yu-Shu Wu Earth

  8. 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)

    Schechter, D.S.

    1997-12-01T23:59:59.000Z

    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.

  9. Integrated seismic study of naturally fractured tight gas reservoirs. Technical progress report, October 1, 1992--December 31, 1992

    SciTech Connect (OSTI)

    Nur, A.

    1993-01-21T23:59:59.000Z

    This was the fifth quarter of the contract. During this quarter we (1) got approval for the NEPA requirements related to the field work, (2) placed the subcontract for the field data acquisition, (3) completed the field work, and (4) began processing the seismic data. As already reported, the field data acquisition was at Acomo`s Powder River Basin site in southeast Wyoming. This is a low permeability fractured site, with both gas and oil present. The reservoir is highly compartmentalized, due to the low permeability, with the fractures providing the only practical drainage paths for production. The two formations of interest are: The Niobrara: a fractured shale and limey shale to chalk, which is a reservoir rock, but also its own source rock. The Frontier: a tight sandstone lying directly below the Niobrara, brought into contact with it by an unconformity. The fractures are thought to lie in a roughly northwest-southeast trend, along the strike of a flexure, which forms one of the boundaries of the basin.

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

    E-Print Network [OSTI]

    Abu-Hassoun, Amer H.

    2009-05-15T23:59:59.000Z

    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...

  11. Integrated seismic study of naturally fractured tight gas reservoirs. Technical progress report, January 1, 1993--March 31, 1993

    SciTech Connect (OSTI)

    Mavko, G.; Nur, A.

    1993-04-26T23:59:59.000Z

    During this quarter we (1) received the last of the field tapes and survey information for the seismic field data acquisition which was finished at the very end of the previous quarter, (2) began the large task of processing the seismic data, (3) collected well logs and other informination to aid in the interpretation, and (4) initiated some seismic modeling studies. As already reported, the field data acquisition was at Amoco`s Powder River Basin site in southeast Wyoming. This is a low permeability fractured site, with both gas and oil present. The reservoir is highly compartmentalized, due to the low permeability, with the fractures providing the only practical drainage paths for production. The two formations of interest are: The Niobrara: a fractured shale and limey shale to chalk, which is a reservoir rock, but also its own source rock. The Frontier: a tight sandstone lying directly below the Niobrara, brought into contact with it by an unconformity. The fractures are thought to lie in a roughly northwest-southeast trend, along the strike of a flexure, which forms one of the boundaries of the basin.

  12. Studying Hydraulic Fracturing through Time-variant Seismic Anisotropy

    E-Print Network [OSTI]

    Liu, Qifan

    2013-10-01T23:59:59.000Z

    . Studying seismic anisotropy by shear wave splitting can help us better understand the relationship between hydraulic fracturing and fracture systems. Shear wave splitting can be caused by fracturing and also can naturally take place in most sedimentary...

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

    E-Print Network [OSTI]

    Lu, Zhiming

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

  14. Fluid Flow Simulation in Fractured Reservoirs

    E-Print Network [OSTI]

    Sarkar, Sudipta

    2002-01-01T23:59:59.000Z

    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 ...

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

    SciTech Connect (OSTI)

    LORENZ,JOHN C.; COOPER,SCOTT P.

    2000-12-20T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    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

    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).

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

    SciTech Connect (OSTI)

    Knight, Bill; Schechter, David S.

    2001-11-19T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Gary Mavko

    2000-10-01T23:59:59.000Z

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

  19. Genesis of fault hosted carbonate fracture cements in a naturally high CO2 province, South Viking Graben, UK North Sea 

    E-Print Network [OSTI]

    Lee, David Robert

    2013-07-01T23:59:59.000Z

    The Late Jurassic Brae oilfields in the South Viking Graben of the northern North Sea contain naturally high concentrations of carbon dioxide (up to 35 mol %). Fields immediately adjacent to the graben bounding fault ...

  20. Flight Testing of an Advanced Airborne Natural Gas Leak Detection System

    SciTech Connect (OSTI)

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

    2005-10-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    SPATIAL PYRAMID MINING FOR LOGO DETECTION IN NATURAL SCENES Jim Kleban University of California of logos appearing in real world scenes. By indexing representative examples by the mined rules we can measure. Logos are localized in an image via density-based clustering of matched features. Precision vs

  2. Hydraulic Fracturing (Vermont)

    Broader source: Energy.gov [DOE]

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

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

    SciTech Connect (OSTI)

    Jerry Myers

    2005-04-15T23:59:59.000Z

    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.

  4. BTEX biodegradation in fractured shale

    SciTech Connect (OSTI)

    O`Cleirigh, D.; Coryea, H. [Roy F. Weston, Inc., Austin, TX (United States); Christopher, M.; Vaughn, C. [Roy F. Weston, Inc., Houston, TX (United States)

    1997-12-31T23:59:59.000Z

    A petroleum hydrocarbon groundwater plume was identified at a Federal Aviation Administration (FAA) facility in Oklahoma. The affected area had an average BTEX concentration of 3.8 mg/L. Previous aquifer tests indicated preferential groundwater flow paths resulting from natural fractures present in the aquifer formation (primarily shale). A pneumatic fracturing pilot study was performed to evaluate the technology`s effectiveness in creating a more isotropic aquifer. As part of the study, pre-fracture/post-fracture pump tests were performed. Pre-fracture and post-fracture graphs confirmed the study`s hypothesis that pneumatic fracturing would eliminate preferential flow paths and increase groundwater yield. Based on the successful pneumatic fracturing test, an area within the petroleum hydrocarbon plume was fractured and a pilot-scale biodegradation system was operated for four months. The remediation system provided groundwater circulation amended with nutrients and oxygen. Results of the study indicated a significant decrease in BTEX concentrations between the injection well and the observation wells. By Day 113, the benzene concentration (0.044 mg/L) at one of the observation wells was less than the desired state cleanup goal of 0.05 mg/L.

  5. Fractured shale reservoirs: Towards a realistic model

    SciTech Connect (OSTI)

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

    1996-09-01T23:59:59.000Z

    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).

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

    E-Print Network [OSTI]

    Marpaung, Fivman

    2008-10-10T23:59:59.000Z

    conductivity is created when proppant slurry is pumped into a hydraulic fracture in low permeability rock. Unlike conventional fracture conductivity tests in which proppant is loaded into the fracture artificially, we pump proppant/ fracturing fluid slurries... different or special methods for completion, stimulation, and/or production techniques to retrieve the resource. Natural gas from coal or coal bed methane, tight gas sands, shale gas, and gas hydrates are all examples of unconventional gas reservoirs...

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

    SciTech Connect (OSTI)

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

    2005-05-01T23:59:59.000Z

    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.

  8. Linked multicontinuum and crack tensor approach for modeling of coupled geomechanics, fluid flow and transport in fractured rock

    E-Print Network [OSTI]

    Rutqvist, J.

    2014-01-01T23:59:59.000Z

    geomechanics in dual-porosity modeling of naturally fractured reservoirs. Society of Petroleum Engineers,

  9. Fracture characterization from seismic measurements in a borehole

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    2015-01-01T23:59:59.000Z

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

  10. Seismic characterization of fractured reservoirs by focusing Gaussian beams

    E-Print Network [OSTI]

    Zheng, Yingcai

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

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

    E-Print Network [OSTI]

    Zamanian, S. Ahmad

    2012-01-01T23:59:59.000Z

    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 ...

  12. Integrated seismic study of naturally fractured tight gas reservoirs. Technical progress report for the period: 7/1/93--9/31/93

    SciTech Connect (OSTI)

    Mavko, G.; Nur, A.

    1993-10-23T23:59:59.000Z

    The study area is located at the southern end of the Powder River Basin in Converse County in east-central Wyoming. It is a low permeability fractured site, with both gas and oil present. Reservoirs are highly compartmentalized due to the low permeabilities, and fractures provide the only practical paths of production. During this eighth quarter of the seismic study of this area, work continued in processing seismic data, collecting additional geological information to aid in the interpretation, and integrating regional structural information and fracture trends with observations of structure in the study area.

  13. Hydraulic fracturing-1

    SciTech Connect (OSTI)

    Not Available

    1990-01-01T23:59:59.000Z

    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.

  14. Analysis of Scattered Signal to Estimate Reservoir Fracture Parameters

    E-Print Network [OSTI]

    Grandi, Samantha K.

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

  15. Fracture Characterization from Scattered Energy: A Case Study

    E-Print Network [OSTI]

    Grandi, Samantha K.

    2006-01-01T23:59:59.000Z

    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. ...

  16. A Cost Effective Multi-Spectral Scanner for Natural Gas Detection

    SciTech Connect (OSTI)

    Yudaya Sivathanu; Jongmook Lim; Vinoo Narayanan; Seonghyeon Park

    2005-12-07T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Gary Mavko

    2004-11-30T23:59:59.000Z

    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

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

    E-Print Network [OSTI]

    Verde Salas, Alexander José

    2014-04-28T23:59:59.000Z

    multipole and local expansions. However, in spite of its immediately apparent application in the geomechanic context, FMM has been limited to only certain fracture problems because those analytical expansions are only available for selected fundamental...

  19. The Functional Potential of Microbial Communities in Hydraulic Fracturing Source Water and Produced Water from Natural Gas Extraction Characterized by Metagenomic Sequencing

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

    Mohan, Arvind Murali; Bibby, Kyle J.; Lipus, Daniel; Hammack, Richard W.; Gregory, Kelvin B.

    2014-10-22T23:59:59.000Z

    Microbial activity in produced water from hydraulic fracturing operations can lead to undesired environmental impacts and increase gas production costs. However, the metabolic profile of these microbial communities is not well understood. Here, for the first time, we present results from a shotgun metagenome of microbial communities in both hydraulic fracturing source water and wastewater produced by hydraulic fracturing. Taxonomic analyses showed an increase in anaerobic/facultative anaerobic classes related to Clostridia, Gammaproteobacteria, Bacteroidia and Epsilonproteobacteria in produced water as compared to predominantly aerobic Alphaproteobacteria in the fracturing source water. The metabolic profile revealed a relative increase in genes responsible formore »carbohydrate metabolism, respiration, sporulation and dormancy, iron acquisition and metabolism, stress response and sulfur metabolism in the produced water samples. These results suggest that microbial communities in produced water have an increased genetic ability to handle stress, which has significant implications for produced water management, such as disinfection.« less

  20. Relative Permeability of Fractured Rock

    SciTech Connect (OSTI)

    Mark D. Habana

    2002-06-30T23:59:59.000Z

    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.

  1. 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...

  2. Detection probability enhancement as a natural feature of Local Hidden Variable models (and Quantum Mechanics too?)

    E-Print Network [OSTI]

    Rodriguez, David

    2011-01-01T23:59:59.000Z

    Experimental tests of Bell inequalities often require supplementary assumptions, one of the usual ones being the "no-enhancement" assumption. Here we show how an already well known Local Hidden Variables (LHV) model for the Clauser-Horne-Shimony-Holt inequality, when extended to account for the probabilities of detection when the polarizers are removed (such as how it would need to be done in a test of the Clauser-Horne inequality), gives rise, as the most natural feature, to the so-called "enhancement" (breaking of the no-enhancement assumption formulated by Clauser and Horne themselves for the operational expression of their inequality). Aside from exposing that key role of enhancement, our work is useful (at least in our case it has been) to gain understanding on some other known results. We also add some comments that we think may be thought-provoking.

  3. 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)

    Schechter, D.S.

    1996-12-17T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Jerry Myers

    2003-05-13T23:59:59.000Z

    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.

  5. A Handbook for the Application of Seismic Methods for Quantifying Naturally Fractured Gas Reservoirs in the San Juan Basin, New Mexico

    E-Print Network [OSTI]

    2004-01-01T23:59:59.000Z

    data in the Mesaverde was to perform the analysis on the reservoir rock (lithology): sand, not shale.reservoir and in the formations above the Lewis shale the datadata could not be explained without the fracture-induced anisotropy in the reservoir and above the Lewis shale.

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

    Open Energy Info (EERE)

    nearly parallel to the maximum horizontal stress. In this favorable situation, hydraulic injections will tend both to reactivate natural fractures at low pressures, and to...

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

    SciTech Connect (OSTI)

    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

    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.

  8. Fracture Properties From Seismic Scattering

    E-Print Network [OSTI]

    Burns, Daniel R.

    2007-01-01T23:59:59.000Z

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

  9. Seismic characterization of fractures

    E-Print Network [OSTI]

    JM Carcione

    2014-06-07T23:59:59.000Z

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

  10. 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)

    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

    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.

  11. Discovery of a natural CO2 seep in the German North Sea: Implications for shallow dissolved gas and seep detection

    E-Print Network [OSTI]

    Wehrli, Bernhard

    2010; published 5 March 2011. [1] A natural carbon dioxide (CO2) seep was discovered during conditions of CO2 bubble and plume seepage and potential flux paths to the atmosphere. Shallow bubble release will be difficult to detect as bubbles dissolve very rapidly (within meters). Bubbleplume modeling further shows

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

    SciTech Connect (OSTI)

    Jerry Myers

    2003-11-12T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Jerry Myers

    2004-05-12T23:59:59.000Z

    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.

  14. Feasibility of a borehole VHF radar technique for fracture mapping

    SciTech Connect (OSTI)

    Chang, H.T.

    1984-01-01T23:59:59.000Z

    Experiments were conducted to establish the feasibility of a downhole high-frequency electromagnetic technique for location of fractures in the vicinity of boreholes. An existing flame-cut slot in granite was filled with salt water to simulate a brine-filled fracture. A transmitter consisting of a phased dual-dipole array arranged to provide a directional signal toward the fracture was installed in a borehole opposite the fracture. A receiver operated at 30 to 300 MHz was also located in the same borehole. The radar returns from the simulated fracture were detectable in boreholes located at distances of up to 12 meters from the fracture. These results indicate for the first time the feasibility of a downhole VHF radar for use in a single borehole for detection of fractures located away from the borehole.

  15. Visual-Based Emotion Detection for Natural Man-Machine Interaction

    E-Print Network [OSTI]

    Berns, Karsten

    realized with a combination of a haar-cascade classifier and a contrast filter. The detected feature points

  16. A Thermoelastic Hydraulic Fracture Design Tool for Geothermal Reservoir Development

    SciTech Connect (OSTI)

    Ahmad Ghassemi

    2003-06-30T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    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

    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).

  18. Seventh International Conference on Biaxial/Multiaxial Fatigue and Fracture, Berlin, 2004, pp. 329-334 FATIGUE CRACK NUCLEATION AND GROWTH IN FILLED NATURAL RUBBER

    E-Print Network [OSTI]

    Fatemi, Ali

    -334 FATIGUE CRACK NUCLEATION AND GROWTH IN FILLED NATURAL RUBBER SUBJECTED TO MULTIAXIAL STRESS STATES W.V. Mars1 and A. Fatemi2 1 Cooper Tire and Rubber Company, 701 Lima Ave., Findlay, Ohio 45840, USA 2 crack nucleation and growth in filled natural rubber under a wide range of multiaxial stress

  19. Recent advances in hydraulic fracturing

    SciTech Connect (OSTI)

    Gidley, J.L.

    1989-01-01T23:59:59.000Z

    This book is a reference to the application of significant technological advances in hydraulic fracturing. It features illustrative problems to demonstrate specific applications of advanced technologies. Chapters examine pretreatment formation evaluation, rock mechanics and fracture geometry, 2D and 3D fracture-propagation models, propping agents and fracture conductivity, fracturing fluids and additives, fluid leakoff, flow behavior, proppant transport, treatment design, well completions, field implementation, fracturing-pressure analysis, postfracture formation evaluation, fracture azimuth and geometry determination, and economics of fracturing.

  20. High velocity impact fracture

    E-Print Network [OSTI]

    Teng, Xiaoqing

    2005-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Forbis, Robert E.

    2014-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    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

    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.

  3. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, Jeffrey R.; Glaser, Steven D.

    2008-01-01T23:59:59.000Z

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

  4. Grasp Detection from Human ECoG during Natural Reach-to-Grasp Movements

    E-Print Network [OSTI]

    , Freiburg, Germany, 4 Department of Bioengineering and Department of Electrical and Electronic Engineering analysis was able to retrieve the time- point of grasp with high reliability and only few false detections. Best performance was achieved using a combination of signal components from time and frequency domains

  5. Fractures in oriented Devonian-shale cores from the Appalachian Basin. Vol. 1

    SciTech Connect (OSTI)

    Evans, M.A.

    1980-01-01T23:59:59.000Z

    Examination of thirteen oriented Devonian-shale cores from the Appalachian Basin revealed considerable fracturing and shearing at depth. Fracture frequency and orientation measurements were made on the fractures in each core. Fractures and associated structures were differentiated into core-induced fractures, unmineralized natural fractures, mineralized natural fractures, slickensided fractures, and slickenlines. Core-induced fractures exhibit a consistent northeast orientation both areally and with depth. This consistency indicates the presence of an anisotropy which is interpreted to be related to an east to northeast trending maximum compressive stress developed in eastern North America by the convective flow in the mantle associated with spreading along the Mid-Atlantic Ridge. Natural fracture, slickenside, and slickenline orientations are related to: (1) northwest directed tectonic compressive stresses associated with Alleghenian deformation, (2) stresses associated with local faulting, and (3) the same east to northeast maximum compressive stress responsible for the core-induced fractures. Higher frequencies of natural fractures and slickensides are associated primarily with incompetent, high-organic shales. Natural fractures occur most frequently in the Marcellus Shale, Tully Limestone, Geneseo Shale, West Falls Formation, and the Lower Huron Member of the Ohio Shale. Slickensided fractures occur most frequently in the Marcellus Shale, Tully Limestone, Geneseo Shale, West Falls Formation, base of the Java Formation, and Lower Huron and Cleveland Members of the Ohio Shale. These observations are consistent with a fracture facies concept that proposes fracture development in shales that have acted as decollement zones during Alleghenian deformation. Detailed reports are included in Volume 2 for each of the thirteen cores investigated. 25 figures, 4 tables.

  6. 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)

    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

    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.

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

    E-Print Network [OSTI]

    Linkov, Igor

    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 ...

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

    SciTech Connect (OSTI)

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

    2012-12-01T23:59:59.000Z

    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.

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

    Open Energy Info (EERE)

    Shale Gas Application in Hydraulic Fracturing Market is likely to grow at a rate of 6.46%, owing to increased natural gas demand Home > Groups > Renewable Energy RFPs Wayne31jan's...

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

    Open Energy Info (EERE)

    OF SHEAR-WAVE SPLITTING Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE...

  11. Natural circulation loop using liquid nitrogen for cryo-detection system

    SciTech Connect (OSTI)

    Choi, Yeon Suk [Korea Basic Science Institute, 169-148 Gwahak-ro, Yuseong-gu, Daejeon, 305-806 (Korea, Republic of)

    2014-01-29T23:59:59.000Z

    The natural circulation loop is designed for the cryogenic insert in a Fourier transform ion cyclotron resonance (FTICR) mass spectrometer. Sensitivity is the key parameter of a FTICR mass spectrometer and the cryo-cooling of the pre-amplifier can reduce the thermal noise level and thereby improve the signal-to-noise ratio. The pre-amplifier consisted of non-magnetic materials is thermally connected to the cooling loop which is passing through the flange maintaining ultra-high vacuum in the ion cell. The liquid nitrogen passes through inside of the loop to cool the pre-amplifier indirectly. At the end, a cryocooler is located to re-condense nitrogen vapor generated due to the heat from the pre-amplifier. The circulating fluid removes heat from the pre-amplifier and transports it to the cryocooler or heat sink. In this paper the natural circulation loop for cryogenic pre-amplifier is introduced for improving the sensitivity of cryo-detector. In addition, the initial cool-down of the system by a cryocooler is presented and the temperature of the radiation shield is discussed with respect to the thickness of shield and the thermal radiation load.

  12. assisted coronoid fracture: Topics by E-print Network

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

    carbonate fields and heavily influence the productivity... Li, Allen 2014-08-10 7 3D seismic attribute-assisted fracture detection in the Middle Devonian Marcellus Shale, Greene...

  13. ON THE SIMULATION OF INCOMPRESSIBLE, MISCIBLE DISPLACEMENT IN A NATURALLY

    E-Print Network [OSTI]

    Arbogast, Todd

    in a naturally fractured petroleum reservoir. Fluid flow is described in the fracture system and in each matrix. -- porous medium, double porosity, miscible displacement, fractured reservoir, finite element method. AMS compared to the size of the entire reservoir), the system of fractures may be thought of as a porous medium

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

    E-Print Network [OSTI]

    Lolon, Elyezer P.

    2006-04-12T23:59:59.000Z

    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...

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

    E-Print Network [OSTI]

    Lolon, Elyezer P.

    2006-04-12T23:59:59.000Z

    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...

  16. 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

  17. Suspensions in hydraulic fracturing

    SciTech Connect (OSTI)

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

    1996-12-31T23:59:59.000Z

    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.

  18. FRACTURING FLUID CHARACTERIZATION FACILITY

    SciTech Connect (OSTI)

    Subhash Shah

    2000-08-01T23:59:59.000Z

    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.

  19. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, J R; Glaser, Steven D

    2007-01-01T23:59:59.000Z

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

  20. Can a fractured caprock self-heal?

    E-Print Network [OSTI]

    Elkhoury, JE; Elkhoury, JE; Detwiler, RL; Ameli, P

    2015-01-01T23:59:59.000Z

    characterization of fractured reservoirs. J. Geophys. Eng.fractured carbonates caused by flow of CO 2 -rich brine under reservoirreservoirs. We present results from two experiments in fractured

  1. 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]

    Aljeshi, Hussain Abdulhadi A.

    2012-07-16T23:59:59.000Z

    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...

  2. Field evaluation of the British Gas elastic-wave vehicle for detecting stress corrosion cracking in natural gas transmission pipelines. Final report, June 1995

    SciTech Connect (OSTI)

    Culbertson, D.L.; Whitney, C.E.

    1995-07-01T23:59:59.000Z

    The objective of this project was to provide the gas pipeline industry with a more comprehensive understanding of the capabilities of the elastic-wave, in-line inspection system developed by British Gas (BG) for detecting stress corrosion cracking (SCC) in natural gas transmission pipelines.

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

    E-Print Network [OSTI]

    Ahmed, Ibraheem 1987-

    2012-11-30T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Ahmad Ghassemi

    2009-10-01T23:59:59.000Z

    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.

  5. Reservoir fracture characterizations from seismic scattered waves

    E-Print Network [OSTI]

    Fang, Xinding

    2012-01-01T23:59:59.000Z

    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 ...

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

    SciTech Connect (OSTI)

    Gao, Dengliang

    2013-03-01T23:59:59.000Z

    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.

  7. Fracture induced anisotropy in viscoelastic media

    E-Print Network [OSTI]

    santos,,,

    ... seismology and mining. Fractures constitute the sources of earthquakes, and hydrocarbon and geothermal reservoirs are mainly composed of fractured rocks.

  8. 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...

  9. 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...

  10. Multiple-point statistical prediction on fracture networks at Yucca Mountain

    SciTech Connect (OSTI)

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

    2009-05-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Correa Castro, Juan

    2011-08-08T23:59:59.000Z

    EVALUATION AND EFFECT OF FRACTURING FLUIDS ON FRACTURE CONDUCTIVITY IN TIGHT GAS RESERVOIRS USING DYNAMIC FRACTURE CONDUCTIVITY TEST A Thesis by JUAN CARLOS CORREA CASTRO Submitted to the Office of Graduate Studies of Texas A... in Tight Gas Reservoirs Using Dynamic Fracture Conductivity Test Copyright 2011 Juan Carlos Correa Castro EVALUATION AND EFFECT OF FRACTURING FLUIDS ON FRACTURE CONDUCTIVITY IN TIGHT GAS RESERVOIRS USING DYNAMIC FRACTURE CONDUCTIVITY TEST A...

  12. Radionuclide Transport in Fracture-Granite Interface Zones

    SciTech Connect (OSTI)

    Hu, Q; Mori, A

    2007-09-12T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Ali, Mohammed

    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

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

    E-Print Network [OSTI]

    Ogbechie, Joachim Nwabunwanne

    2012-02-14T23:59:59.000Z

    Gen and NFflow) for fracture modeling of a shale gas reservoir and also studies the interaction of the different fracture properties on reservoir response. The most important results of the study are that a uniform fracture network distribution and fracture...

  15. Procedure for estimating fracture energy from fracture surface roughness

    DOE Patents [OSTI]

    Williford, Ralph E. (Kennewick, WA)

    1989-01-01T23:59:59.000Z

    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.

  16. Numerical simulation of hydraulic fracturing

    E-Print Network [OSTI]

    Warner, Joseph Barnes

    1987-01-01T23:59:59.000Z

    ~ared that the results of such treatments were not always adequately described by the two-dimensional models. With recent advances in hydraulic fracturing and computing technology, attempts have been made to formulate more realistic fracture models. These three...NUMERICAL SIMULATION OF HYDRAULIC FRACTURING A Thesis by JOSEPH BARNES WARNER Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1987 Maj or Subj ect...

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

    SciTech Connect (OSTI)

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

    1997-08-01T23:59:59.000Z

    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.

  18. Fracture model for cemented aggregates

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

    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

    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.

  19. Flow dynamics and solute transport in unsaturated rock fractures

    SciTech Connect (OSTI)

    Su, G. W.

    1999-10-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Cossio Santizo, Manuel

    2012-10-19T23:59:59.000Z

    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...

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

    E-Print Network [OSTI]

    Fletcher, Sarah Marie

    2012-01-01T23:59:59.000Z

    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 ...

  2. The characterization of c-rate dependent hard carbon anode fracture induced by lithium intercalation

    E-Print Network [OSTI]

    Villalón, Thomas A., Jr. (Thomas Aanthony)

    2014-01-01T23:59:59.000Z

    This study sought to evaluate hard carbon's fracture characteristics under different cycling rates due to its lithium solid solubility and isotropic nature. In addition to the evaluation, an electrochemical shock map was ...

  3. The use of broadband microseisms for hydraulic fracture mapping

    SciTech Connect (OSTI)

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

    1993-08-01T23:59:59.000Z

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

  4. Interferometric hydrofracture microseism localization using neighboring fracture

    E-Print Network [OSTI]

    Poliannikov, Oleg V.

    2011-05-19T23:59:59.000Z

    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. ...

  5. Interferometric hydrofracture microseism localization using neighboring fracture

    E-Print Network [OSTI]

    Poliannikov, Oleg V.

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

  6. Fracture compliance estimation using borehole tube waves

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

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

  7. FRACTURE FAILURE CRITERIA OF SOFC PEN STRUCTURE

    SciTech Connect (OSTI)

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

    2007-04-30T23:59:59.000Z

    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.

  8. Design and construction of an experiment for two-phase flow in fractured porous media

    SciTech Connect (OSTI)

    Ayala, R.E.G.; Aziz, K.

    1993-08-01T23:59:59.000Z

    In numerical reservoir simulation naturally fractured reservoirs are commonly divided into matrix and fracture systems. The high permeability fractures are usually entirely responsible for flow between blocks and flow to the wells. The flow in these fractures is modeled using Darcy`s law and its extension to multiphase flow by means of relative permeabilities. The influence and measurement of fracture relative permeability for two-phase flow in fractured porous media have not been studied extensively, and the few works presented in the literature are contradictory. Experimental and numerical work on two-phase flow in fractured porous media has been initiated. An apparatus for monitoring this type of flow was designed and constructed. It consists of an artificially fractured core inside an epoxy core holder, detailed pressure and effluent monitoring, saturation measurements by means of a CT-scanner and a computerized data acquisition system. The complete apparatus was assembled and tested at conditions similar to the conditions expected for the two-phase flow experiments. Fine grid simulations of the experimental setup-were performed in order to establish experimental conditions and to study the effects of several key variables. These variables include fracture relative permeability and fracture capillary pressure. The numerical computations show that the flow is dominated by capillary imbibition, and that fracture relative permeabilities have only a minor influence. High oil recoveries without water production are achieved due to effective water imbibition from the fracture to the matrix. When imbibition is absent, fracture relative permeabilities affect the flow behavior at early production times.

  9. Fracture of Thermosetting Polymers: Experiments and Modeling

    E-Print Network [OSTI]

    Benzerga, Amine; Burgess, Brad

    2011-08-04T23:59:59.000Z

    , have come under scrutiny. The cases consist of a carbon fiber resin matrix. The resin can be any one of a number of epoxies, most germane of which is E862. This resin has the effect of strengthening the overall casing structure, but the full nature... of a resin known as epoxy E862, which is a polymer resin currently explored by NASA researchers, and then model this behavior using FEM. In the early 1990's, successful computational methodologies for modeling fracture of metal-matrix composites...

  10. Exploring the physicochemical processes that govern hydraulic fracture through laboratory

    E-Print Network [OSTI]

    Belmonte A; Connelly P

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

  11. 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...

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

    E-Print Network [OSTI]

    Cappa, F.

    2009-01-01T23:59:59.000Z

    an Engineered Fractured Geothermal Reservoir. Example of theinteractions in a fractured carbonate reservoir inferredwithin a shallow fractured carbonate reservoir. Fracture

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

    SciTech Connect (OSTI)

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

    1999-03-01T23:59:59.000Z

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

  14. Application of the Ensemble Kalman Filter to Estimate Fracture Parameters in Unconventional Horizontal Wells by Downhole Temperature Measurements

    E-Print Network [OSTI]

    Gonzales, Sergio Eduardo

    2013-07-23T23:59:59.000Z

    in the area of oil shales, in order to design more efficient, accurate and cost-effective hydraulic fracture jobs, there must be a better understanding of the relationships between reservoir and fracture parameters, and how they affect the performance... methane (CBM), basin-centered gas, shale gas, gas hydrates, natural bitumen, and oil shale deposits. Typically, such accumulations require specialized extraction technology (e.g., dewatering of CBM, massive fracturing programs for shale gas, steam and...

  15. Slator Ranch fracture optimization study

    SciTech Connect (OSTI)

    Ventura, J.L.

    1985-07-01T23:59:59.000Z

    The Las Ovejas (Lobo) field in Zapata County, TX, is being developed actively. The field was discovered on Tenneco Oil EandP's Slator Ranch lease with the successful completion of the Sanchez-O'Brien Vaquillas Ranch Well 1. Tenneco operates all of the 17,712-acre (71 678 X 10/sup 3/-m/sup 2/) lease (with the exception of a 320-acre (1295 X 10/sup 3/-m/sup 2/) tract assigned to the Vaquillas Ranch Well 1) and has successfully completed five wells in the Lobo field subsequent to the discovery well. The Lobo interval in the Slator Ranch area is a tight gas sand, and all these wells require fracture stimulation. Because a successful fracture is essential for a good Lobo completion and because hydraulic fracturing represents a significant portion of the completed well cost, it is important to optimize this phase of the completion. The purpose of this study was to determine the following for Slator Ranch Lobo completions: an optimum fracture length as a function of permeability; whether wells should be tailed-in with bauxite, or fractured with all bauxite or sand (if an optimum tail-in does exist, to determine the optimum tail-in for a fixed fracture length as a function of permeability); the drainage area and abandonment pressure for Slator Ranch Well 2; the effect of compression on reserves; and closure pressure as a function of time and distance along the fracture for Slator Ranch Well 2.

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

    E-Print Network [OSTI]

    Underwood, Jarrod

    2013-11-15T23:59:59.000Z

    carbonate reservoir were labeled A through F to protect proprietary information included in this research. A 2% potassium chloride solution was used for the acid system and fracture conductivity measurements to prevent clay swelling. Injection temperature...

  17. Optimization of fracture treatment designs

    E-Print Network [OSTI]

    Rueda, Jose Ignacio

    1992-01-01T23:59:59.000Z

    using the type curves published by Holditch et al2O. n f H r lic Fracture Pro a ation imula or In 1955, the first model to simulate the propagation of a vertical hydraulic fracture was developed by Khristianovitch and Zheltov O (K-Z model). This two... . . . . 93 97 LIST OF TABLES Table Page 5. I Reservoir and well data for base case example 54 5. 2 Fracture design data for base case example . 54 5. 3 Economic data for base case example . . 54 5. 4 Comparison of the methods used in STIMOP and LPOP...

  18. Fracture of aluminum naval structures

    E-Print Network [OSTI]

    Galanis, Konstantinos, 1970-

    2007-01-01T23:59:59.000Z

    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. ...

  19. Sensitivity analysis of fracture scattering

    E-Print Network [OSTI]

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

    2010-01-01T23:59:59.000Z

    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, ...

  20. FRACTURE STIMULATION IN ENHANCED GEOTHERMAL

    E-Print Network [OSTI]

    Stanford University

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

  1. Seismic anisotropy of fractured rock

    E-Print Network [OSTI]

    M. Schoenberg, C. M. Sayers

    2000-02-18T23:59:59.000Z

    of seismic anisotropy to determine the orientation of fracture sets is of ... this assumption of noninteraction does not imply that the ... conventional (2-subscript) condensed 6 x 6 matrix notation,. 11. 6, while ... have simple physical interpretations.

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

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    2011-01-01T23:59:59.000Z

    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 ...

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

    E-Print Network [OSTI]

    Narasimhan, T.N.

    2014-01-01T23:59:59.000Z

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

  4. Elastic properties of saturated porous rocks with aligned fractures

    E-Print Network [OSTI]

    2003-12-02T23:59:59.000Z

    This unexpected result is caused by the wave-induced flow of fluids between pores and fractures. ..... For non-fractured rock setting fracture weaknesses. DN and ...

  5. Tracer Testing for Estimating Heat Transfer Area in Fractured Reservoirs

    E-Print Network [OSTI]

    Pruess, Karsten; van Heel, Ton; Shan, Chao

    2004-01-01T23:59:59.000Z

    Heat Flow in Fractured Reservoirs, SPE Advanced TechnologyTransfer Area in Fractured Reservoirs Karsten Pruess 1 , Tonbehavior arises in fractured reservoirs. As cold injected

  6. asymmetric hydraulic fracture: Topics by E-print Network

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

    from the fractured shale 17 RPSEA UNCONVENTIONAL GAS CONFERENCE 2012: Geology, the Environment, Hydraulic Fracturing Engineering Websites Summary: Fracturing Experiment Overview...

  7. advanced hydraulic fracturing: Topics by E-print Network

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

    from the fractured shale 18 RPSEA UNCONVENTIONAL GAS CONFERENCE 2012: Geology, the Environment, Hydraulic Fracturing Engineering Websites Summary: Fracturing Experiment Overview...

  8. Multiwell experiment: Fracturing experiments

    SciTech Connect (OSTI)

    Warpinski, N.R.; Sattler, A.R.; Branagan, P.T.; Cipolla, C.

    1987-01-01T23:59:59.000Z

    Because of the complexity of the stimulation, no conventional analyses were useful, so we decided to concentrate on the minifrac to provide important fracture parameters. The minifrac was conducted in an identical manner to the pressure-up and pad stages of the stimulation. Figure 1 shows two initial pressure-history match calculations that were performed to model the minifrac. We found that the pressure behavior could not be matched with any normal behavior. Examining the field pressure data, we see that the interesting feature is the sudden flattening in the pressure at a level 1050 psi above the closure stress during pumping and the rapid drop to this same level at shut-in, after which the pressure decreases much more slowly. We first tried to match this behavior using enhanced height growth. While height growth can flatten the pressure during pumping, it also causes a very slow pressure decline at shut-in. We also tried additional leakoff height as height grew, but this could not flatten the pressure as much as needed. Finally, we tried an accelerated leakoff condition above 1050 psi. We did this by increasing the leakoff coefficient by a constant factor above some threshold value. To keep the results smooth and code convergent, we actually linearly phased in the increased leakoff between 1000 and 1100 psi. The final result of these calculations is shown in Figure 2; a factor of 50 increase in the leakoff coefficient was required to match the data for pressures above 1050 psi.

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

    E-Print Network [OSTI]

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

    2000-01-01T23:59:59.000Z

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

  10. 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...

  11. Mathematical modeling of a CO?b2?s-enriched waterflood in fractured reservoirs

    E-Print Network [OSTI]

    Little, Stanley Brian

    1990-01-01T23:59:59.000Z

    are impossible to measure. The model also uses an approximation to the fluid transfer between the fracture and matrix according to other published work. Kleppe and Morse& presented a two-dimensional numerical model simulating the flow of water and oil... Chair of Advisory Committee: Dr. Ching H. Wu This paper presents a mathematical model describing imbibition recovery by a CO&-enriched waterflood for the flow problem of a one dimensional fracture surrounded by a porous medium. A natural extension...

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

    E-Print Network [OSTI]

    Kaul, Sandeep P.

    2004-09-30T23:59:59.000Z

    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...

  13. Predicting dissolution patterns in variable aperture fractures: 1. Development and evaluation of an enhanced depth-averaged computational model

    SciTech Connect (OSTI)

    Detwiler, R L; Rajaram, H

    2006-04-21T23:59:59.000Z

    Water-rock interactions within variable-aperture fractures can lead to dissolution of fracture surfaces and local alteration of fracture apertures, potentially transforming the transport properties of the fracture over time. Because fractures often provide dominant pathways for subsurface flow and transport, developing models that effectively quantify the role of dissolution on changing transport properties over a range of scales is critical to understanding potential impacts of natural and anthropogenic processes. Dissolution of fracture surfaces is controlled by surface-reaction kinetics and transport of reactants and products to and from the fracture surfaces. We present development and evaluation of a depth-averaged model of fracture flow and reactive transport that explicitly calculates local dissolution-induced alterations in fracture apertures. The model incorporates an effective mass transfer relationship that implicitly represents the transition from reaction-limited dissolution to transport-limited dissolution. We evaluate the model through direct comparison to previously reported physical experiments in transparent analog fractures fabricated by mating an inert, transparent rough surface with a smooth single crystal of potassium dihydrogen phosphate (KDP), which allowed direct measurement of fracture aperture during dissolution experiments using well-established light transmission techniques [Detwiler, et al., 2003]. Comparison of experiments and simulations at different flow rates demonstrate the relative impact of the dimensionless Peclet and Damkohler numbers on fracture dissolution and the ability of the computational model to simulate dissolution. Despite some discrepancies in the small-scale details of dissolution patterns, the simulations predict the evolution of large-scale features quite well for the different experimental conditions. This suggests that our depth-averaged approach to simulating fracture dissolution provides a useful approach for extending laboratory results that are often limited in scale to scales that are more representative of geologic processes of interest.

  14. Laboratory investigation of crushed salt consolidation and fracture healing

    SciTech Connect (OSTI)

    Not Available

    1987-01-01T23:59:59.000Z

    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.

  15. Method for directional hydraulic fracturing

    DOE Patents [OSTI]

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

    1994-01-01T23:59:59.000Z

    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.

  16. Acoustic Character Of Hydraulic Fractures In Granite

    E-Print Network [OSTI]

    Paillet, Frederick I.

    1983-01-01T23:59:59.000Z

    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 ...

  17. A Global Model for Fracture Falloff Analysis

    E-Print Network [OSTI]

    Marongiu-Porcu, Matteo

    2014-10-29T23:59:59.000Z

    The reservoir permeability is an essential input for the optimum design of modern hydraulic fracture treatments, which are undeniably the crucial technology involved in the development of tight and/or unconventional gas reservoirs. The fracture...

  18. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, Jeffrey R.; Glaser, Steven D.

    2008-01-01T23:59:59.000Z

    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

  19. 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.

  20. Discrete fracture modeling for fractured reservoirs using Voronoi grid blocks

    E-Print Network [OSTI]

    Gross, Matthew Edward

    2007-09-17T23:59:59.000Z

    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...

  1. Hydraulic Fracture: multiscale processes and moving

    E-Print Network [OSTI]

    Peirce, Anthony

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

  2. Hydraulic Fracture: multiscale processes and moving

    E-Print Network [OSTI]

    Peirce, Anthony

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

  3. Regulation of Hydraulic Fracturing in California

    E-Print Network [OSTI]

    Kammen, Daniel M.

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

  4. 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)

    Not Available

    1981-01-01T23:59:59.000Z

    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.

  5. Laboratory analysis of fluid flow and solute transport through a variably saturated fracture embedded in porous tuff

    SciTech Connect (OSTI)

    Chuang, Y.; Haldeman, W.R.; Rasmussen, T.C.; Evans, D.D. [Arizona Univ., Tucson, AZ (USA). Dept. of Hydrology and Water Resources

    1990-02-01T23:59:59.000Z

    Laboratory techniques are developed that allow concurrent measurement of unsaturated matrix hydraulic conductivity and fracture transmissivity of fractured rock blocks. Two Apache Leap tuff blocks with natural fractures were removed from near Superior, Arizona, shaped into rectangular prisms, and instrumented in the laboratory. Porous ceramic plates provided solution to block tops at regulated pressures. Infiltration tests were performed on both test blocks. Steady flow testing of the saturated first block provided estimates of matrix hydraulic conductivity and fracture transmissivity. Fifteen centimeters of suction applied to the second block top showed that fracture flow was minimal and matrix hydraulic conductivity was an order of magnitude less than the first block saturated matrix conductivity. Coated-wire ion-selective electrodes monitored aqueous chlorided breakthrough concentrations. Minute samples of tracer solution were collected with filter paper. The techniques worked well for studying transport behavior at near-saturated flow conditions and also appear to be promising for unsaturated conditions. Breakthrough curves in the fracture and matrix, and a concentration map of chloride concentrations within the fracture, suggest preferential flows paths in the fracture and substantial diffusion into the matrix. Average travel velocity, dispersion coefficient and longitudinal dispersivity in the fracture are obtained. 67 refs., 54 figs., 23 tabs.

  6. Geomechanical Simulation of Fluid-Driven Fractures

    SciTech Connect (OSTI)

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

    2012-11-30T23:59:59.000Z

    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.

  7. RESEARCH PROGRAM ON FRACTURED PETROLEUM RESERVOIRS

    SciTech Connect (OSTI)

    Abbas Firoozabadi

    2002-04-12T23:59:59.000Z

    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.

  8. Interaction between Injection Points during Hydraulic Fracturing

    E-Print Network [OSTI]

    Hals, Kjetil M D

    2012-01-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Nakagawa, S.; Myer, L.R.

    2009-06-15T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Underwood, Jarrod

    2013-11-15T23:59:59.000Z

    (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...

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

    E-Print Network [OSTI]

    Nelson, J.T.

    2009-01-01T23:59:59.000Z

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

  12. Predicting fracture in micron-scale polycrystalline silicon MEMS structures.

    SciTech Connect (OSTI)

    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

    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.

  13. Drill-back studies examine fractured, heated rock

    SciTech Connect (OSTI)

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

    1990-01-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2008-07-01T23:59:59.000Z

    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.

  15. Apparatus and method for monitoring underground fracturing

    DOE Patents [OSTI]

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

    1999-08-10T23:59:59.000Z

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

  16. Apparatus and method for monitoring underground fracturing

    DOE Patents [OSTI]

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

    1999-08-10T23:59:59.000Z

    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.

  17. Method of fracturing a geological formation

    DOE Patents [OSTI]

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

    1990-01-01T23:59:59.000Z

    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.

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

    Open Energy Info (EERE)

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

  19. Wave Propagation in Fractured Poroelastic Media

    E-Print Network [OSTI]

    2014-06-22T23:59:59.000Z

    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,

  20. Fracturing technology poised for rapid advancement

    SciTech Connect (OSTI)

    Von Flatern, R.

    1993-10-01T23:59:59.000Z

    This paper summarizes the advances and current status of hydraulic fracturing and the industry's ability to design and predict the results. Although modeling techniques have improved over the years, there still is no model which can be considered very reliable. The paper considers alternatives to help improve the reliability of these models such as on-site quality control. This quality control aspect entails the site-specific tailoring of a fracturing fluid to be better suited for the target fracturing zone environment and adjusting the fluid properties accordingly. It also entails various methods for fluid injection and placement of propping agents. Some future trends in hydraulic fracturing are also discussed.

  1. Fracture permeability and seismic wave scattering ŒPoroelastic ...

    E-Print Network [OSTI]

    Seiji Nakagawa

    2010-02-03T23:59:59.000Z

    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 ...

  2. 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...

  3. 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...

  4. Microseismic Tracer Particles for Hydraulic Fracturing

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

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

  5. Indirect fracture delineation in a carbonate reservoir: The Upper Jurassic Hanifa of Abqaiq field, Saudi Arabia

    SciTech Connect (OSTI)

    Bailey, D.L. (Saudi Aramco, Dhahran (Saudi Arabia))

    1991-03-01T23:59:59.000Z

    Abqaiq field is a northeast-trending anticline approximately 60 km long and 12 km wide and contains several reservoirs. The Hanifa Reservoir is approximately 100 m thick and consists of fine-grained, muddy limestone with subordinate dolomite and anhydrite. Since discovery of the Hanifa oil pool in 1947, pressure fluctuations have indicated communication with the overlying Arab-D Reservoir. Welltest permeability measurements are approximately 40 times higher than core permeability measurements of the Hanifa. This divergence of Hanifa permeability measurements combined with the indicated Arab-D communication suggests the presence of a natural fracture network. Direct observations of Hanifa cores reveal common, sub-vertical fractures with average apertures <200 microns. With limited core coverage and no oriented cores, a new technique was needed to delineate the areas affected by fractures. A technique combining indirect fracture indicators was devised for Abqaiq field and can be applied to other, similar fields. The actual flow system of the Abqaiq Hanifa is a complex interaction between matrix porosity/permeability and fracture permeability or enhanced permeability. Future development plans allow for low matrix permeability access to much of the Hanifa storage space and high fracture permeability both within the Hanifa and connecting to the Arab-D Reservoir.

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

    SciTech Connect (OSTI)

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

    1994-08-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Densirimongkol, Jurairat

    2010-10-12T23:59:59.000Z

    in fracture conductivity and unsuccessful stimulation treatment. In early years, because of the increase in the success of proppant fracturing, proppant partial monolayer has been put forward as a method that helps generate the maximum fracture conductivity...

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

    E-Print Network [OSTI]

    Zheng, Yingcai

    2012-01-01T23:59:59.000Z

    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 ...

  9. Efficient Double-Beam Characterization for Fractured Reservoir

    E-Print Network [OSTI]

    Zheng, Yingcai

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

  10. Incorporating Rigorous Height Determination into Unified Fracture Design

    E-Print Network [OSTI]

    Pitakbunkate, Termpan

    2010-10-12T23:59:59.000Z

    to find the maximum productivity index for a given proppant amount. Then, the dimensionless fracture conductivity index corresponding to the maximum productivity index can be computed. The penetration ration, the fracture length, and the propped fracture...

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

    E-Print Network [OSTI]

    Xue, Liang, 1973-

    2007-01-01T23:59:59.000Z

    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 ...

  12. INJECTION AND THERMAL BREAKTHROUGH IN FRACTURED GEOTHERMAL RESERVOIRS

    E-Print Network [OSTI]

    Bodvarsson, Gudmundur S.

    2012-01-01T23:59:59.000Z

    injection into a fractured reservoir system. A reservoirIn the case of fractured reservoirs, Equations (25) and (26)c ww q a >> For fractured reservoirs, the former expression

  13. Laboratory-scale fracture conductivity created by acid etching 

    E-Print Network [OSTI]

    Pournik, Maysam

    2009-05-15T23:59:59.000Z

    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...

  14. A Political Ecology of Hydraulic Fracturing for Natural Gas in

    E-Print Network [OSTI]

    Scott, Christopher

    ! Background of Marcellus Shale Gas Play ! Current Events: The Case of PA ! Geography of Fracking in Study

  15. Continuous Model Updating and Forecasting for a Naturally Fractured Reservoir

    E-Print Network [OSTI]

    Almohammadi, Hisham

    2013-07-26T23:59:59.000Z

    . Such capabilities allow for a paradigm change in which reservoir management can be looked at as a strategy that enables a semi-continuous process of model updates and decision optimizations instead of being periodic or reactive. This is referred to as closed...

  16. TRACER ANALYSIS IN A FRACTURED GEO'MERMAL RESERVOIR: FIELD RESULTS FROM WAIRAKEI, NEW ZEALAND

    E-Print Network [OSTI]

    Stanford University

    TRACER ANALYSIS IN A FRACTURED GEO'MERMAL RESERVOIR: FIELD RESULTS FROM WAIRAKEI, NEW ZEALAND . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 -V- #12;Chapter I INTRODUCTION Interwell tracers have been used extensively in oil reservoirs to detect reservoir heterogeneities. High permeability production zones can channel a disproportionate

  17. Field-Scale Effective Matrix Diffusion Coefficient for Fractured Rock: Results From Literature Survey

    E-Print Network [OSTI]

    Zhou, Quanlin; Liu, Hui Hai; Molz, Fred J.; Zhang, Yingqi; Bodvarsson, Gudmundur S.

    2008-01-01T23:59:59.000Z

    Dispersed fluid flow in fractured reservoirs: An analysis ofa hydraulically fractured granite geothermal reservoir, Soc.

  18. Images of Fracture Sustainability Test on Stripa Granite

    SciTech Connect (OSTI)

    Tim Kneafsey

    2014-05-11T23:59:59.000Z

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

  19. Images of Fracture Sustainability Test on Stripa Granite

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

    Tim Kneafsey

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

  20. acetabular internal fracture: Topics by E-print Network

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

    stiness and uid ow L Lafayette, IN 47907-1397, USA Accepted 7 October 1999 Abstract Fracture specic stiness and uid ow through a single fracture under...

  1. age fracture mechanics: Topics by E-print Network

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

    stiness and uid ow L Lafayette, IN 47907-1397, USA Accepted 7 October 1999 Abstract Fracture specic stiness and uid ow through a single fracture under...

  2. alloys fracture mechanics: Topics by E-print Network

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

    stiness and uid ow L Lafayette, IN 47907-1397, USA Accepted 7 October 1999 Abstract Fracture specic stiness and uid ow through a single fracture under...

  3. applying fracture mechanics: Topics by E-print Network

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

    stiness and uid ow L Lafayette, IN 47907-1397, USA Accepted 7 October 1999 Abstract Fracture specic stiness and uid ow through a single fracture under...

  4. advanced fracture characterization: Topics by E-print Network

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

    stiness and uid ow L Lafayette, IN 47907-1397, USA Accepted 7 October 1999 Abstract Fracture specic stiness and uid ow through a single fracture under...

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

    Open Energy Info (EERE)

    flow paths. We applied this technique to seismic data collected during a massive hydraulic fracturing (MHF) treatment and found that the fracture planes determined by the...

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

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

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

  7. Monitoring of Fracture Cri0cal Steel Bridges

    E-Print Network [OSTI]

    Minnesota, University of

    #12;Monitoring of Fracture Cri0cal Steel Bridges: Acous0c Emission Sensors system on other fracture cri0cal steel bridges #12;Project Impact #12;Thank

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

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

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

  9. 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....

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

    SciTech Connect (OSTI)

    Petti, Jason P.; Kalan, Robert J.

    2011-12-01T23:59:59.000Z

    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.

  11. Modeling of Acid Fracturing in Carbonate Reservoirs

    E-Print Network [OSTI]

    Al Jawad, Murtada s

    2014-06-05T23:59:59.000Z

    equations are used to draw 3D velocity and pressure profiles. Part of the fluid diffuses or leaks off into the fracture walls and dissolves part of the fracture face according to the chemical reaction below. 2H^(+)(aq) + CO((2-)/3) ? H_(2 )CO_(3)(aq) ? CO...

  12. Accounting for Remaining Injected Fracturing Fluid 

    E-Print Network [OSTI]

    Zhang, Yannan

    2013-12-06T23:59:59.000Z

    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...

  13. Accounting for Remaining Injected Fracturing Fluid

    E-Print Network [OSTI]

    Zhang, Yannan

    2013-12-06T23:59:59.000Z

    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...

  14. Fracture of synthetic diamond M. D. Droty

    E-Print Network [OSTI]

    Ritchie, Robert

    of synthetic polycrystalline diamond make it a promising material for many structural applications studies on the fracture toughness of polycrystalline diamond,29 primarily due to the difficultiesFracture of synthetic diamond M. D. Droty Ctystallume, 3506 Bassett Street, Santa Clara, California

  15. Finite Conductivity Fractures in Elliptical Coordinates

    E-Print Network [OSTI]

    Stanford University

    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

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

    SciTech Connect (OSTI)

    Detwiler, Russell

    2014-04-30T23:59:59.000Z

    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.

  17. Hydraulic fracturing slurry transport in horizontal pipes

    SciTech Connect (OSTI)

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

    1990-09-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Wang, Wenxin

    2006-04-12T23:59:59.000Z

    This thesis presents and develops efficient and effective methodologies for optimal hydraulic fracture design and fracture performance evaluation. These methods incorporate algorithms that simultaneously optimize all of ...

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

    SciTech Connect (OSTI)

    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

    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.

  20. FRACTURE DETECTION IN CRYSTALLINE ROCK USING ULTRASONIC SHEAR WAVES

    E-Print Network [OSTI]

    Waters, K.H.

    2011-01-01T23:59:59.000Z

    water interface. Thus, no S^| wave energy should penetrate asimilar situation some P wave energy is transmitted into thesome sort of "parasitic" P wave energy created by the S u H

  1. FRACTURE DETECTION IN CRYSTALLINE ROCK USING ULTRASONIC SHEAR WAVES

    E-Print Network [OSTI]

    Waters, K.H.

    2011-01-01T23:59:59.000Z

    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,

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

    E-Print Network [OSTI]

    Wei Chen

    directions, inferred from the shear-wave rotation analysis on all four lines, trend consistently ..... In the most general form, the result can be applied to a system of

  3. FRACTURE DETECTION IN CRYSTALLINE ROCK USING ULTRASONIC SHEAR WAVES

    E-Print Network [OSTI]

    Waters, K.H.

    2011-01-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Poston, S.W.

    1991-12-31T23:59:59.000Z

    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.

  5. Fracture-resistant lanthanide scintillators

    DOE Patents [OSTI]

    Doty, F. Patrick (Livermore, CA)

    2011-01-04T23:59:59.000Z

    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.

  6. High Energy Gas Fracturing Test

    SciTech Connect (OSTI)

    Schulte, R.

    2001-02-27T23:59:59.000Z

    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.

  7. Coupling schemes for modeling hydraulic fracture propagation using the XFEM

    E-Print Network [OSTI]

    Peirce, Anthony

    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

  8. Calibration of hydraulic and tracer tests in fractured media

    E-Print Network [OSTI]

    Politècnica de Catalunya, Universitat

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

  9. Statistical analysis of liquid seepage in partially saturated heterogeneous fracture systems

    SciTech Connect (OSTI)

    Liou, T.S.

    1999-12-01T23:59:59.000Z

    Field evidence suggests that water flow in unsaturated fracture systems may occur along fast preferential flow paths. However, conventional macroscale continuum approaches generally predict the downward migration of water as a spatially uniform wetting front subjected to strong inhibition into the partially saturated rock matrix. One possible cause of this discrepancy may be the spatially random geometry of the fracture surfaces, and hence, the irregular fracture aperture. Therefore, a numerical model was developed in this study to investigate the effects of geometric features of natural rock fractures on liquid seepage and solute transport in 2-D planar fractures under isothermal, partially saturated conditions. The fractures were conceptualized as 2-D heterogeneous porous media that are characterized by their spatially correlated permeability fields. A statistical simulator, which uses a simulated annealing (SA) algorithm, was employed to generate synthetic permeability fields. Hypothesized geometric features that are expected to be relevant for seepage behavior, such as spatially correlated asperity contacts, were considered in the SA algorithm. Most importantly, a new perturbation mechanism for SA was developed in order to consider specifically the spatial correlation near conditioning asperity contacts. Numerical simulations of fluid flow and solute transport were then performed in these synthetic fractures by the flow simulator TOUGH2, assuming that the effects of matrix permeability, gas phase pressure, capillary/permeability hysteresis, and molecular diffusion can be neglected. Results of flow simulation showed that liquid seepage in partially saturated fractures is characterized by localized preferential flow, along with bypassing, funneling, and localized ponding. Seepage pattern is dominated by the fraction of asperity contracts, and their shape, size, and spatial correlation. However, the correlation structure of permeability field is less important than the spatial correlation of asperity contacts. A faster breakthrough was observed in fractures subjected to higher normal stress, accompanied with a nonlinearly decreasing trend of the effective permeability. Interestingly, seepage dispersion is generally higher in fractures with intermediate fraction of asperity contacts; but it is lower for small or large fractions of asperity contacts. However, it may become higher if the ponding becomes significant. Transport simulations indicate that tracers bypass dead-end pores and travel along flow paths that have less flow resistance. Accordingly, tracer breakthrough curves generally show more spreading than breakthrough curves for water. Further analyses suggest that the log-normal time model generally fails to fit the breakthrough curves for water, but it is a good approximation for breakthrough curves for the tracer.

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

    E-Print Network [OSTI]

    Correa Castro, Juan

    2011-08-08T23:59:59.000Z

    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...

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

    SciTech Connect (OSTI)

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

    1995-11-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2013-11-19T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    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

    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.

  14. Universal asymptotic umbrella for hydraulic fracture modeling

    E-Print Network [OSTI]

    Linkov, Aleksandr M

    2014-01-01T23:59:59.000Z

    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.

  15. Gas condensate damage in hydraulically fractured wells

    E-Print Network [OSTI]

    Adeyeye, Adedeji Ayoola

    2004-09-30T23:59:59.000Z

    Company. The well was producing a gas condensate reservoir and questions were raised about how much drop in flowing bottomhole pressure below dewpoint would be appropriate. Condensate damage in the hydraulic fracture was expected to be of significant...

  16. Geomechanical review of hydraulic fracturing technology

    E-Print Network [OSTI]

    Arop, Julius Bankong

    2013-01-01T23:59:59.000Z

    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 ...

  17. Fracture induced anisotropy in viscoelastic media

    E-Print Network [OSTI]

    santos,,,

    pp = 28 MPa, Z. ?1. N. = (14.4+3.6i) GPa, Z. ?1. T. = (21 + 2.6i) GPa,. We consider a set of equispaced fractures with L = 1 cm and 80 % binary fractal variations ...

  18. Multiphase flow in fractured porous media

    SciTech Connect (OSTI)

    Firoozabadi, A.

    1995-02-01T23:59:59.000Z

    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.

  19. Dynamic Fracture Toughness of Polymer Composites

    E-Print Network [OSTI]

    Harmeet Kaur

    2012-02-14T23:59:59.000Z

    bar with required instrumentation to obtain load-history and initiation of crack propagation parameters followed by finite element analysis to determine desired dynamic properties. Single edge notch bend(SENB) type geometry is used for Mode-I fracture...

  20. Infiltration and Seepage Through Fractured Welded Tuff

    SciTech Connect (OSTI)

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

    2006-06-20T23:59:59.000Z

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

  1. Anomalous transport through porous and fractured media

    E-Print Network [OSTI]

    Kang, Peter Kyungchul

    2014-01-01T23:59:59.000Z

    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 ...

  2. Higher-Order Compositional Modeling of Three-phase Flow in 3D Fractured Porous Media Using Cross-flow Equilibrium Approach

    E-Print Network [OSTI]

    Moortgat, Joachim

    2013-01-01T23:59:59.000Z

    Numerical simulation of multiphase compositional flow in fractured porous media, when all the species can transfer between the phases, is a real challenge. Despite the broad applications in hydrocarbon reservoir engineering and hydrology, a compositional numerical simulator for three-phase flow in fractured media has not appeared in the literature, to the best of our knowledge. In this work, we present a three-phase fully compositional simulator for fractured media, based on higher-order finite element methods. To achieve computational efficiency, we invoke the cross-flow equilibrium (CFE) concept between discrete fractures and a small neighborhood in the matrix blocks. We adopt the mixed hybrid finite element (MHFE) method to approximate convective Darcy fluxes and the pressure equation. This approach is the most natural choice for flow in fractured media. The mass balance equations are discretized by the discontinuous Galerkin (DG) method, which is perhaps the most efficient approach to capture physical dis...

  3. Fracture Conductivity of the Eagle Ford Shale

    E-Print Network [OSTI]

    Guzek, James J

    2014-07-25T23:59:59.000Z

    , and rock geomechanical properties. Therefore, optimizing conductivity by tailoring a well’s fracturing treatment to local reservoir characteristics is important to the oil and gas industry for economic reasons. The roots of hydraulic fracturing can... of the formation. Sahoo et al. (2013) identified that mineralogy, hydrocarbon filled porosity, and total organic content are most prominent parameters that control Eagle Ford well productivity. Mineral composition determines several geomechanical properties...

  4. Poroelastic response of orthotropic fractured porous media

    SciTech Connect (OSTI)

    Berryman, J.G.

    2010-12-01T23:59:59.000Z

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

  5. FRACTURE TOUGHNESS VARIABILITY IN F82H

    SciTech Connect (OSTI)

    Gelles, David S.; Sokolov, M.

    2003-09-03T23:59:59.000Z

    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.

  6. TRITIUM EFFECTS ON WELDMENT FRACTURE TOUGHNESS

    SciTech Connect (OSTI)

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

    2006-07-17T23:59:59.000Z

    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''.

  7. FRACTURED RESERVOIR E&P IN ROCKY MOUNTAIN BASINS: A 3-D RTM MODELING APPROACH

    SciTech Connect (OSTI)

    P. Ortoleva; J. Comer; A. Park; D. Payne; W. Sibo; K. Tuncay

    2001-11-26T23:59:59.000Z

    Key natural gas reserves in Rocky Mountain and other U.S. basins are in reservoirs with economic producibility due to natural fractures. In this project, we evaluate a unique technology for predicting fractured reservoir location and characteristics ahead of drilling based on a 3-D basin/field simulator, Basin RTM. Recommendations are made for making Basin RTM a key element of a practical E&P strategy. A myriad of reaction, transport, and mechanical (RTM) processes underlie the creation, cementation and preservation of fractured reservoirs. These processes are often so strongly coupled that they cannot be understood individually. Furthermore, sedimentary nonuniformity, overall tectonics and basement heat flux histories make a basin a fundamentally 3-D object. Basin RTM is the only 3-D, comprehensive, fully coupled RTM basin simulator available for the exploration of fractured reservoirs. Results of Basin RTM simulations are presented, that demonstrate its capabilities and limitations. Furthermore, it is shown how Basin RTM is a basis for a revolutionary automated methodology for simultaneously using a range of remote and other basin datasets to locate reservoirs and to assess risk. Characteristics predicted by our model include reserves and composition, matrix and fracture permeability, reservoir rock strength, porosity, in situ stress and the statistics of fracture aperture, length and orientation. Our model integrates its input data (overall sedimentation, tectonic and basement heat flux histories) via the laws of physics and chemistry that describe the RTM processes to predict reservoir location and characteristics. Basin RTM uses 3-D, finite element solutions of the equations of rock mechanics, organic and inorganic diagenesis and multi-phase hydrology to make its predictions. As our model predicts reservoir characteristics, it can be used to optimize production approaches (e.g., assess the stability of horizontal wells or vulnerability of fractures to production-induced formation pressure drawdown). The Piceance Basin (Colorado) was chosen for this study because of the extensive set of data provided to us by federal agencies and industry partners, its remaining reserves, and its similarities with other Rocky Mountain basins. We focused on the Rulison Field to test our ability to capture details in a well-characterized area. In this study, we developed a number of general principles including (1) the importance of even subtle flexure in creating fractures; (2) the tendency to preserve fractures due to the compressibility of gases; (3) the importance of oscillatory fracture/flow cycles in the expulsion of natural gas from source rock; and (4) that predicting fractures requires a basin model that is comprehensive, all processes are coupled, and is fully 3-D. A major difficulty in using Basin RTM or other basin simulator has been overcome in this project; we have set forth an information theory technology for automatically integrating basin modeling with classical database analysis; this technology also provides an assessment of risk. We have created a relational database for the Piceance Basin. We have developed a formulation of devolatilization shrinkage that integrates organic geochemical kinetics into incremental stress theory, allowing for the prediction of coal cleating and associated enhancement of natural gas expulsion from coal. An estimation of the potential economic benefits of the technologies developed or recommended here is set forth. All of the above findings are documented in this report.

  8. Critical Chemical-Mechanical Couplings that Define Permeability Modifications in Pressure-Sensitive Rock Fractures

    SciTech Connect (OSTI)

    Derek Elsworth; Abraham Grader; Susan Brantley

    2007-04-25T23:59:59.000Z

    This work examined and quantified processes controlling changes in the transport characteristics of natural fractures, subjected to coupled thermal-mechanical-chemical (TMC) effects. Specifically, it examined the effects of mineral dissolution and precipitation mediated by mechanical effects, using laboratory through-flow experiments concurrently imaged by X-ray CT. These were conducted on natural and artificial fractures in cores using water as the permeant. Fluid and mineral mass balances are recorded and are correlated with in-sample saturation, porosity and fracture aperture maps, acquired in real-time by X-ray CT-imaging at a maximum spatial resolution of 15-50 microns per pixel. Post-test, the samples were resin-impregnated, thin-sectioned, and examined by microscopy to define the characteristics of dissolution and precipitation. The test-concurrent X-ray imaging, mass balances, and measurements of permeability, together with the post-test microscopy, were used to define dissolution/precipitation processes, and to constrain process-based models. These models define and quantify key processes of pressure solution, free-face dissolution, and shear-dilation, and the influence of temperature, stress level, and chemistry on the rate of dissolution, its distribution in space and time, and its influence on the mechanical and transport properties of the fracture.

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

    E-Print Network [OSTI]

    Doe, T.

    2010-01-01T23:59:59.000Z

    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

  10. An Analytical Solution for Slug-Tracer Tests in Fractured Reservoirs

    E-Print Network [OSTI]

    Shan, Chao; Pruess, Karsten

    2005-01-01T23:59:59.000Z

    Tracer Tests in Fractured Reservoirs Chao Shan and Karstenof chemicals or heat in fractured reservoirs is stronglyin a water-saturated fractured reservoir. The solution shows

  11. Aligned vertical fractures, HTI reservoir symmetry, and Thomsen seismic anisotropy parameters for polar media

    E-Print Network [OSTI]

    Berryman, James G.

    2008-01-01T23:59:59.000Z

    waves in such fractured reservoirs (Hsu and Schoenberg,i.e. , for cracked/fractured reservoirs), the vertical phasemore closely. FRACTURED RESERVOIRS AND CRACK-INFLUENCE

  12. Effects of non-condensible gases on fluid recovery in fractured geothermal reservoirs

    E-Print Network [OSTI]

    Bodvarsson, Gudmundur S.; Gaulke, Scott

    1986-01-01T23:59:59.000Z

    Simu- lations in Fractured Reservoirs,” Lawrence Berkeleyfrom a twctphase fractured reservoir. T h e results obtainedRecovery in Fractured Geothermal Reservoirs Gudmundur S.

  13. Modeling interfacial fracture in Sierra.

    SciTech Connect (OSTI)

    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

    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.

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

    E-Print Network [OSTI]

    Alghamdi, Abdulwahab

    2006-08-16T23:59:59.000Z

    ................................................................................................. 29 4.2.1 Initial Pad Volume ........................................................................... 29 4.2.2 Acid Strength and Volume...............................................................30 V... stages of pad fluids and acids.11 The reaction of HCl with carbonate formations is fast, especially at high temperatures. This means that the acid will not be able to penetrate deeply down the fracture, which may affect the outcome of acid fracturing...

  15. A Physically Based Approach for Modeling Multiphase Fracture-Matrix Interaction in Fractured Porous Media

    SciTech Connect (OSTI)

    Wu, Yu-Shu; Pan, Lehua; Pruess, Karsten

    2004-03-15T23:59:59.000Z

    Modeling fracture-matrix interaction within a complex multiple phase flow system is a key issue for fractured reservoir simulation. Commonly used mathematical models for dealing with such interactions employ a dual- or multiple-continuum concept, in which fractures and matrix are represented as overlapping, different, but interconnected continua, described by parallel sets of conservation equations. The conventional single-point upstream weighting scheme, in which the fracture relative permeability is used to represent the counterpart at the fracture-matrix interface, is the most common scheme by which to estimate flow mobility for fracture-matrix flow terms. However, such a scheme has a serious flaw, which may lead to unphysical solutions or significant numerical errors. To overcome the limitation of the conventional upstream weighting scheme, this paper presents a physically based modeling approach for estimating physically correct relative permeability in calculating multiphase flow between fractures and the matrix, using continuity of capillary pressure at the fracture-matrix interface. The proposed approach has been implemented into two multiphase reservoir simulators and verified using analytical solutions and laboratory experimental data. The new method is demonstrated to be accurate, numerically efficient, and easy to implement in dual- or multiple-continuum models.

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

    E-Print Network [OSTI]

    Wythe, Kathy

    2013-01-01T23:59:59.000Z

    of Fracture Fluid Performance in Oil Shale with Surfactant Additives by X-Ray Tomography Methods (Crisman Institute: Schechter) Re-Use of Produced Waters as Hydraulic Fracturing Fluids (Crisman Institute: Nasr-El-Din) In a joint House Commi#20;ee...

  17. ACOUSTIC DETECTING AND LOCATING GAS PIPE LINE INFRINGEMENT

    SciTech Connect (OSTI)

    John L. Loth; Gary J. Morris; George M. Palmer; Richard Guiler; Patrick Browning

    2004-10-31T23:59:59.000Z

    The extensive network of high-pressure natural gas transmission pipelines covering the United States provides an important infrastructure for our energy independence. Early detection of pipeline leaks and infringements by construction equipment, resulting in corrosion fractures, presents an important aspect of our national security policy. The National Energy Technology Laboratory Strategic Center for Natural Gas (SCVG) is and has been funding research on various applicable techniques. The WVU research team has focused on monitoring pipeline background acoustic signals generated and transmitted by gas flowing through the gas inside the pipeline. In case of a pipeline infringement, any mechanical impact on the pipe wall, or escape of high-pressure gas, generates acoustic signals traveling both up and down stream through the gas. Sudden changes in flow noise are detectable with a Portable Acoustic Monitoring Package (PAMP), developed under this contract. It incorporates a pressure compensating microphone and a signal- recording device. Direct access to the gas inside the line is obtained by mounting such a PAMP, with a 1/2 inch NPT connection, to a pipeline pressure port found near most shut-off valves. An FFT of the recorded signal subtracted by that of the background noise recorded one-second earlier appears to sufficiently isolate the infringement signal to allow source interpretation. Using cell phones for data downloading might allow a network of such 1000-psi rated PAMP's to acoustically monitor a pipeline system and be trained by neural network software to positively identify and locate any pipeline infringement.

  18. ACOUSTIC DETECTING AND LOCATING GAS PIPE LINE INFRINGEMENT

    SciTech Connect (OSTI)

    John L. Loth; Gary J. Morris; George M. Palmer; Richard Guiler; Patrick Browning

    2004-12-01T23:59:59.000Z

    The extensive network of high-pressure natural gas transmission pipelines covering the United States provides an important infrastructure for our energy independence. Early detection of pipeline leaks and infringements by construction equipment, resulting in corrosion fractures, presents an important aspect of our national security policy. The National Energy Technology Laboratory Strategic Center for Natural Gas (SCVG) is and has been funding research on various applicable techniques. The WVU research team has focused on monitoring pipeline background acoustic signals generated and transmitted by gas flowing through the gas inside the pipeline. In case of a pipeline infringement, any mechanical impact on the pipe wall, or escape of high-pressure gas, generates acoustic signals traveling both up and down stream through the gas. Sudden changes in flow noise are detectable with a Portable Acoustic Monitoring Package (PAMP), developed under this contract. It incorporates a pressure compensating microphone and a signal- recording device. Direct access to the gas inside the line is obtained by mounting such a PAMP, with a 1/2 inch NPT connection, to a pipeline pressure port found near most shut-off valves. An FFT of the recorded signal subtracted by that of the background noise recorded one-second earlier appears to sufficiently isolate the infringement signal to allow source interpretation. Using cell phones for data downloading might allow a network of such 1000-psi rated PAMP's to acoustically monitor a pipeline system and be trained by neural network software to positively identify and locate any pipeline infringement.

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

    E-Print Network [OSTI]

    Wylie, Sara Ann

    2011-01-01T23:59:59.000Z

    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 ...

  20. CT measurements of two-phase flow in fractured porous media

    SciTech Connect (OSTI)

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

    1997-06-01T23:59:59.000Z

    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.

  1. Experimental analysis of the extension to shear fracture transition in Berea Sandstone

    E-Print Network [OSTI]

    Bobich, Jennifer Kay

    2005-11-01T23:59:59.000Z

    and follows Coulomb behavior; however, the angle between the fracture surface and ??1 increases continuously with Pc. Fracture surfaces characteristic of the extension to shear fracture transition appear as linked, stepped extension fractures; the length...

  2. Reservoir Fracture Mapping using Microearthquakes: Austin Chalk, Giddings Field, TX and 76 Field, Clinton Co., KY.

    E-Print Network [OSTI]

    SPE 36651 Reservoir Fracture Mapping using Microearthquakes: Austin Chalk, Giddings Field, TX and enhanced recovery, production operations in fracture- dominated oil and gas reservoirs. Borehole geophones to study reservoir fracture systems. Methods currently applied to study fracture systems include tilt

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

    E-Print Network [OSTI]

    Shekhar, Ravi

    2009-05-15T23:59:59.000Z

    and amplitude variation with offset (AVO) results for our example model predicts that CO2 is easier to detect than brine in the fractured reservoirs. The effects of geochemical processes on seismics are simulated by time-lapse modeling for t = 1000 years. My...

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

    E-Print Network [OSTI]

    Wessling, S.

    2009-01-01T23:59:59.000Z

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

  5. IPIRG programs - advances in pipe fracture technology

    SciTech Connect (OSTI)

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

    1997-04-01T23:59:59.000Z

    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.

  6. Uncertainty analysis for probabilistic pipe fracture evaluations in LBB applications

    SciTech Connect (OSTI)

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

    1997-04-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Huang, Hai; Plummer, Mitchell; Podgorney, Robert

    2013-02-01T23:59:59.000Z

    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.

  8. Hydraulic Fracture Monitoring: A Jonah Field Case Study

    E-Print Network [OSTI]

    Seher, T.

    2011-01-01T23:59:59.000Z

    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 ...

  9. Fractional Diffusion Modeling of Electromagnetic Induction in Fractured Rocks

    E-Print Network [OSTI]

    Ge, Jianchao

    2014-08-11T23:59:59.000Z

    -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...

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

    E-Print Network [OSTI]

    never asked for anything back. First is Professor Wolfgang Knauss, who guided me in the solid to be consistent with fracture under mixed-mode loading. High-speed movies of the fracture events and blast wave

  11. Laboratory-scale fracture conductivity created by acid etching

    E-Print Network [OSTI]

    Pournik, Maysam

    2009-05-15T23:59:59.000Z

    the closure stress. While there have been several experimental studies conducted on acid fracturing, most of these have not scaled experiments to field conditions and did not account for the effect of rock weakening and etching pattern. Hence, acid fracture...

  12. Development and testing of an advanced acid fracture conductivity apparatus

    E-Print Network [OSTI]

    Zou, ChunLei

    2006-08-16T23:59:59.000Z

    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...

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

    E-Print Network [OSTI]

    Rahman, Sharif

    Chakraborty, Sharif Rahman * Department of Mechanical and Industrial Engineering, College of Engineering three multiscale models, including sequential, invasive, and concurrent models, for fracture analysis-intensity factors or accurate probability of fracture initiation. The concurrent multiscale model is sufficiently

  14. FRACTURE AND HYDROLOGY DATA FROM FIELD STUDIES AT STRIPA, SWEDEN

    E-Print Network [OSTI]

    Gale, J.E.

    2010-01-01T23:59:59.000Z

    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

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

    E-Print Network [OSTI]

    Chi, Shihong

    2006-01-01T23:59:59.000Z

    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 ...

  16. Effects of subsurface fracture interactions on surface deformation

    E-Print Network [OSTI]

    Jerry, Ruel (Ruel Valentine)

    2013-01-01T23:59:59.000Z

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

  17. On equivalence of thinning fluids used for hydraulic fracturing

    E-Print Network [OSTI]

    Linkov, Alexander

    2012-01-01T23:59:59.000Z

    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...

  18. 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.

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

    E-Print Network [OSTI]

    Nino Penaloza, Andrea

    2013-05-01T23:59:59.000Z

    to those in actual acid fracture treatments. After acid etching, fracture conductivity is measured at different closure stresses. This research work presents a systematic study to investigate the effect of temperature, rock-acid contact time and initial...

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

    E-Print Network [OSTI]

    Song, Bo

    2014-08-28T23:59:59.000Z

    A large volume of fracturing fluid that may include slick water and various sorts of additives is injected into shale formations along with proppant to create hydraulic fractures which define a stimulated shale volume a shale gas well will actually...

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

    E-Print Network [OSTI]

    Alampi, Ann M

    2014-01-01T23:59:59.000Z

    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 ...

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

    E-Print Network [OSTI]

    Poliannikov, Oleg V.

    2011-01-01T23:59:59.000Z

    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 ...

  3. Mechanistic fracture criteria for the failure of human cortical bone

    SciTech Connect (OSTI)

    Nalla, Ravi K.; Kinney, John H.; Ritchie, Robert O.

    2002-12-13T23:59:59.000Z

    A mechanistic understanding of fracture in human bone is critical to predicting fracture risk associated with age and disease. Despite extensive work, a mechanistic framework for describing how the underlying microstructure affects the failure mode in bone is lacking.

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

    E-Print Network [OSTI]

    Nino Penaloza, Andrea

    2013-05-01T23:59:59.000Z

    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...

  5. On the fracture toughness of advanced materials

    SciTech Connect (OSTI)

    Launey, Maximilien E.; Ritchie, Robert O.

    2008-11-24T23:59:59.000Z

    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}.

  6. Compartmentalization analysis using discrete fracture network models

    SciTech Connect (OSTI)

    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

    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.

  7. Fracture Toughness Prediction for MWCNT Reinforced Ceramics

    SciTech Connect (OSTI)

    Henager, Charles H.; Nguyen, Ba Nghiep

    2013-09-01T23:59:59.000Z

    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.

  8. Seismic velocity and Q anisotropy in fractured poroelastic media

    E-Print Network [OSTI]

    Introduction. Seismic wave propagation through fractures is an important subject in hydrocarbon exploration geophysics, mining and reservoir characterization ...

  9. Experimental and Analytical Research on Fracture Processes in ROck

    SciTech Connect (OSTI)

    Herbert H.. Einstein; Jay Miller; Bruno Silva

    2009-02-27T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

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

    2015-03-18T23:59:59.000Z

    Hip fracture risk is known to be related to material properties of the proximal femur, but fracture prediction studies adding richer quantitative computed tomography (QCT) measures to dual energy X-ray (DXA)-based methods have shown limited...

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

    E-Print Network [OSTI]

    Peirce, Anthony

    Hydraulic Fractures: multiscale phenomena, asymptotic and numerical solutions SANUM Conference (UMN) Eduard Siebrits (SLB) #12;2 Outline · Examples of hydraulic fractures · Governing equations well stimulation Fracturing Fluid Proppant #12;5 Quarries #12;6 Magma flow Tarkastad #12;7 Model EQ 1

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

    E-Print Network [OSTI]

    Peirce, Anthony

    Hydraulic Fractures: multiscale phenomena, asymptotic and numerical solutions CSIRO CSS TCP Detournay (UMN) Eduard Siebrits (SLB) #12;2 Outline · Examples of hydraulic fractures · Governing equations well stimulation Fracturing Fluid Proppant #12;5 Quarries #12;6 Magma flow Tarkastad #12;7 Model EQ 1

  13. Role of seepage forces on hydraulic fracturing and failure patterns

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    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

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

    E-Print Network [OSTI]

    Zhang, Junjing

    2014-07-10T23:59:59.000Z

    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...

  15. Poroelastic modeling of fracture-seismic wave interaction

    SciTech Connect (OSTI)

    Nakagawa, Seiji

    2008-08-15T23:59:59.000Z

    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.

  16. EFFECTS OF WATER INJECTION INTO FRACTURED GEOTHERMAL RESERVOIRS

    E-Print Network [OSTI]

    Stanford University

    SGP-TR-57 SGP-TR-57 EFFECTS OF WATER INJECTION INTO FRACTURED GEOTHERMAL RESERVOIRS: A SUMMARY INTO FRACTURED GEOTHERMAL RESERVOIRS A SUMMARY OP EXPERImCE WORtDWIDE Roland N. Horne Stanford University ABSTRACT Reinjection of water i n t o fractured geothermal reservoirs holds potential both f o r

  17. 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

  18. 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

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

    E-Print Network [OSTI]

    Zhang, Junjing

    2014-07-10T23:59:59.000Z

    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...

  20. Improved Microseismicity Detection During Newberry EGS Stimulations

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

    Templeton, Dennise

    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.

  1. Improved Microseismicity Detection During Newberry EGS Stimulations

    SciTech Connect (OSTI)

    Templeton, Dennise

    2013-11-01T23:59:59.000Z

    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.

  2. Improved Microseismicity Detection During Newberry EGS Stimulations

    SciTech Connect (OSTI)

    Templeton, Dennise

    2013-10-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Peirce, Anthony

    Simultaneous Growth of Multiple Hydraulic Fractures A.P. Peirce, University of British Columbia and A.P. Bunger 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

  4. Stresses and fractures in the Frontier Formation, Green River Basin, predicted from basin-margin tectonic element interactions

    SciTech Connect (OSTI)

    Lorenz, J.C.

    1996-01-01T23:59:59.000Z

    Natural fractures and in situ stresses commonly dictate subsurface reservoir permeability and permeability anisotropy, as well as the effectiveness of stimulation techniques in low-permeability, natural gas reservoirs. This paper offers an initial prediction for the orientations of the fracture and stress systems in the tight gas reservoirs of the Frontier Formation, in the Green River basin of southwestern Wyoming. It builds on a previous report that addressed fractures and stresses in the western part of the basin and on ideas developed for the rest of the basin, using the principle that thrust faults are capable of affecting the stress magnitudes and orientations in little-deformed strata several hundreds of kilometers in front of a thrust. The prediction of subsurface stresses and natural fracture orientations is an undertaking that requires the willingness to revise models as definitive data are acquired during drilling. The predictions made in this paper are offered with the caveat that geology in the subsurface is always full of surprises.

  5. Identifying Best Practices in Hydraulic Fracturing Using

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    . Treating Rate Medina Treating Pressure Medina Production Remaining Gas Ultimate Gas Gas Months Prod Gas Medina and Whirlpool sands of southwest New York State are considered to be tight gas sands. Most wells, are fractured upon completion to provide economic amounts of gas. #12;SPE 72385 BACKGROUND A dataset

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

    E-Print Network [OSTI]

    Marpaung, Fivman

    2009-05-15T23:59:59.000Z

    ) ............................................................................ 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...

  7. A Triple-Porosity Model for Fractured Horizontal Wells

    E-Print Network [OSTI]

    Alahmadi, Hasan Ali H.

    2010-10-12T23:59:59.000Z

    . 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...

  8. Advanced hydraulic fracturing methods to create in situ reactive barriers

    SciTech Connect (OSTI)

    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

    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.

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

    SciTech Connect (OSTI)

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

    2010-01-10T23:59:59.000Z

    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.

  10. 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)

    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

    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.

  11. Field-Scale Effective Matrix Diffusion Coefficient for FracturedRock: Results From Literature Survey

    SciTech Connect (OSTI)

    Zhou, Quanlin; Liu, Hui Hai; Molz, Fred J.; Zhang, Yingqi; Bodvarsson, Gudmundur S.

    2005-03-28T23:59:59.000Z

    Matrix diffusion is an important mechanism for solutetransport in fractured rock. We recently conducted a literature survey onthe effective matrix diffusion coefficient, Dem, a key parameter fordescribing matrix diffusion processes at the field scale. Forty fieldtracer tests at 15 fractured geologic sites were surveyed and selectedfor study, based on data availability and quality. Field-scale Dem valueswere calculated, either directly using data reported in the literature orby reanalyzing the corresponding field tracer tests. Surveyed dataindicate that the effective-matrix-diffusion-coefficient factor FD(defined as the ratio of Dem to the lab-scale matrix diffusioncoefficient [Dem]of the same tracer) is generally larger than one,indicating that the effective matrix diffusion coefficient in the fieldis comparatively larger than the matrix diffusion coefficient at therock-core scale. This larger value could be attributed to the manymass-transfer processes at different scales in naturally heterogeneous,fractured rock systems. Furthermore, we observed a moderate trend towardsystematic increase in the emDFmDDF value with observation scale,indicating that the effective matrix diffusion coefficient is likely tobe statistically scale dependent. The FD value ranges from 1 to 10,000for observation scales from 5 to 2,000 m. At a given scale, the FD valuevaries by two orders of magnitude, reflecting the influence of differingdegrees of fractured rock heterogeneity at different sites. In addition,the surveyed data indicate that field-scale longitudinal dispersivitygenerally increases with observation scale, which is consistent withprevious studies. The scale-dependent field-scale matrix diffusioncoefficient (and dispersivity) may have significant implications forassessing long-term, large-scale radionuclide and contaminant transportevents in fractured rock, both for nuclear waste disposal and contaminantremediation.

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

    E-Print Network [OSTI]

    Deng, Jiayao

    2011-02-22T23:59:59.000Z

    .) ............................................................................................................. 30 Fig. 2.4 Width profile of a fracture?s cross-section. ..................................................... 34 Fig. 2.5 Fracture?s cross-section approximated by an ellipse. ..................................... 35 Fig. 2.6 Fracture... profile scanned in the lab. .................................................................... 57 Fig. 3.5 Width profiles of fracture surfaces under closure stress 1,000 psi. ................ 58 Fig. 3.6 Width profiles of fracture surfaces...

  13. Characterization of fracture networks for fluid flow analysis

    SciTech Connect (OSTI)

    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

    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.

  14. Permeability and Dispersion Coefficients in Rocks with Fracture Network - 12140

    SciTech Connect (OSTI)

    Lee, C.K.; Htway, M.Z. [Handong Global University, 3 Namsong-ri, Heunghae-eub, Buk-gu, Pohang, Kyungbuk, 791-708 (Korea, Republic of); Yim, S.P. [Korea Atomic Energy Research Institute, P.O.Box 150, Yusong, Daejon, 305-600 (Korea, Republic of)

    2012-07-01T23:59:59.000Z

    Fluid flow and solute transport are considered for a rock medium with a fracture network with regard to the effective permeability and the dispersion coefficients. To investigate the effects of individual fractures a three-fracture system is chosen in which two are parallel and the third one connects the two at different angles. Specifically the micro-cell boundary-value problems(defined through multiple scale analysis) are solved numerically by using finite elements to calculate the permeability and dispersion coefficients. It is shown that the permeability depends significantly on the pattern of the fracture distribution and the dispersion coefficient is influenced by both the externally imposed pressure gradient (which also reflects the flow field) and the direction of the gradient of solute concentration on the macro-scale. From the calculations of the permeability and dispersion coefficients for solute in a rock medium with a fracture network the following conclusions are drawn. 1. The permeability of fractured medium depends on the primary orientation of the fracture network and is influenced by the connecting fractures in the medium. 2. The cross permeability, e.g., permeability in the direction normal to the direction of the external pressure gradient is rather insensitive to the orientation of the fracture network. 3. Calculation of permeability is most efficiently achieved with optimal discretization across individual fractures and is rather insensitive to the discretization along the fracture.. 4. The longitudinal dispersion coefficient Dxx of a fractured medium depends on both the macro-scale concentration gradient and the direction of the flow (pressure gradient). Hence both features must be considered when investigating solute transport in a fractured medium. (authors)

  15. Impact fracture behavior of HT9 duct

    SciTech Connect (OSTI)

    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

    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.

  16. Lisburne Formation fracture characterization and flow modeling

    E-Print Network [OSTI]

    Karpov, Alexandre Valerievich

    2001-01-01T23:59:59.000Z

    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...

  17. Effects of oxygen on fracturing fluids

    SciTech Connect (OSTI)

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

    1995-11-01T23:59:59.000Z

    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.

  18. Development of an analytical solution for thermal single-well injection-withdrawal tests in horizontally fractured reservoirs

    E-Print Network [OSTI]

    Jung, Y.

    2014-01-01T23:59:59.000Z

    Transfer Area in Fractured Reservoirs, paper presented attests in horizontally fractured reservoirs Yoojin Jung Earthtests in horizontally fractured reservoirs where fluid flow

  19. Use of TOUGHREACT to Simulate Effects of Fluid Chemistry on Injectivity in Fractured Geothermal Reservoirs with High Ionic Strength Fluids

    E-Print Network [OSTI]

    Xu, Tianfu; Zhang, Guoxiang; Pruess, Karsten

    2005-01-01T23:59:59.000Z

    swelling in a fractured geothermal reservoir, Proceedings ofon Injectivity in Fractured Geothermal Reservoirs with Highdry rock and hot fractured rock reservoirs in a sustainable

  20. Mesoscale Characterization of Coupled Hydromechanical Behavior of a Fractured Porous Slope in Response to Free Water-Surface Movement

    E-Print Network [OSTI]

    Guglielmi, Y.

    2008-01-01T23:59:59.000Z

    of these effects in fractured reservoirs, at an intermediateinteractions in a fractured carbonate reservoir inferredis a mesoscale fractured carbonate reservoir (30 m × 30 m ×

  1. Fracture testing of Edwards limestone: a statistical treatment 

    E-Print Network [OSTI]

    Redding, David Earl

    1993-01-01T23:59:59.000Z

    Parameters. . 21 8. Goodness-of-Fit Statistic (Alpha) for Rubber Fracture Testing of Edwards Limestone. . 9. Sum of Square Residuals for Predicted Geometry vs. Base Geometry. . 38 10. Residuals in Sigma Theta Maximum at the Median Probability Value... for Predicted Geometry vs. Base Geometry. . 38 LIST OF FIGURES Figure 1. Rubber Fracture Test Geometry. Page 2. Hollow Brass Cylinder Calibration. 13 3. Sigma Theta Max vs. Volume. . 18 4A. Cumulative Probability vs. Sigma Theta Max. Rubber Fracture...

  2. 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...

  3. ankle joint fractures: Topics by E-print Network

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

    for hydrocarbon production, control and manipulation of water supplies events induced by hydraulic fracturing. The effect of a thin weak elastic layer was investigated by Jones...

  4. adjacent compression fractures: Topics by E-print Network

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

    12;MRCM New Approach Multiple Stankewitz, Rich 140 Self-potential observations during hydraulic fracturing University of California eScholarship Repository Summary: hydraulic...

  5. arch fracture intraoperatively: Topics by E-print Network

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

    formation determined. Szymczak, P 2009-01-01 149 Self-potential observations during hydraulic fracturing University of California eScholarship Repository Summary: hydraulic...

  6. acute compression fracture: Topics by E-print Network

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

    12;MRCM New Approach Multiple Stankewitz, Rich 112 Self-potential observations during hydraulic fracturing University of California eScholarship Repository Summary: hydraulic...

  7. acetabular fracture fixation: Topics by E-print Network

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

    knowledge about the po... Wilke, C O 2002-01-01 104 Self-potential observations during hydraulic fracturing University of California eScholarship Repository Summary: hydraulic...

  8. apophyseal ring fracture: 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...

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

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

    code (modeling at the reservoir scale) - CFD: NETL's computational fluid dynamics code (modeling at the fracture scale) * Develop fat-ray double-difference tomography...

  10. 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...

  11. 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;...

  12. Aligned fractures modeled as boundary conditions within saturated ...

    E-Print Network [OSTI]

    2015-03-30T23:59:59.000Z

    e di Geofisica Sperimentale, OGS. SUMMARY. Fractures in a fluid-saturated poroelastic -Biot- medium are very thin, compliant and highly permeable layers.

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

    E-Print Network [OSTI]

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

    2006-08-28T23:59:59.000Z

    Aug 28, 2006 ... pliance and fluid-permeability tensors of a layer containing closely spaced ...... Coupled thermo-hydromechanical processes of fractured media.

  14. 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...

  15. 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....

  16. AN APPROACH TO THE FRACTURE HYDROLOGY AT STRIPA: PRELIMINARY RESULTS

    E-Print Network [OSTI]

    Gale, J.E.

    2010-01-01T23:59:59.000Z

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

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

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

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

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

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

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

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

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

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

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

    Open Energy Info (EERE)

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

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

    Open Energy Info (EERE)

    microearthquake seismorgrams Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: Characterization of subsurface fracture patterns in the...

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

    Open Energy Info (EERE)

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

  3. 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...

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

    E-Print Network [OSTI]

    Wu, Xi

    2014-06-23T23:59:59.000Z

    workflow is illustrated in Figure 3.3. The approach starts with a fracture simulator, which uses a geomechanical model, to calculate fracture width during the pad injection. A hydraulic fracture is created at the defined injection condition. Next, we... be directly found from the output of Fracpro. Table 3.1 shows an output file example from Fracpro for a fracture geometry at the end of a pad injection. The geometry data is restored in an “.fpx” file, named “PROJECT_NAME.fpx” and can be read using any text...

  5. alternate fracture toughness: Topics by E-print Network

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

    specic stiness and uid ow L Lafayette, IN 47907-1397, USA Accepted 7 October 1999 Abstract Fracture specic stiness and uid ow through a single...

  6. arrest fracture toughness: Topics by E-print Network

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

    specic stiness and uid ow L Lafayette, IN 47907-1397, USA Accepted 7 October 1999 Abstract Fracture specic stiness and uid ow through a single...

  7. advanced fracturing technology: Topics by E-print Network

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

    specic stiness and uid ow L Lafayette, IN 47907-1397, USA Accepted 7 October 1999 Abstract Fracture specic stiness and uid ow through a single...

  8. Advanced Hydraulic Fracturing Technology for Unconventional Tight Gas Reservoirs

    SciTech Connect (OSTI)

    Stephen Holditch; A. Daniel Hill; D. Zhu

    2007-06-19T23:59:59.000Z

    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.

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

    Open Energy Info (EERE)

    Distributions Abstract A methodology for analyzing the internal flow characteristics of a fractured geothermal reservoir using tracer-determined residence time distribution curves...

  10. 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)...

  11. Finite element modeling of hydraulic fracturing in 3D

    E-Print Network [OSTI]

    2013-03-22T23:59:59.000Z

    Mar 22, 2013 ... Gautier. A.. Touzelet. S.: Tracer testing of the geothermal heat ex- ... R.: A field demonstra- tion of hydraulic fracturing for solid waste diposal—.

  12. 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...

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

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

    Project title: Stimulation at Desert Peak and Bradys reservoirs: modeling with the coupled THM code FEHM Seismic Fracture Characterization Methods for Enhanced Geothermal Systems...

  14. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighandSWPA / SPRA / USACE LMI-EFRCAddendum 1April 1, 2011 DOE

  15. THERMO-HYDRO-MECHANICAL MODELING OF WORKING FLUID INJECTION AND THERMAL ENERGY EXTRACTION IN EGS FRACTURES AND ROCK MATRIX

    SciTech Connect (OSTI)

    Robert Podgorney; Chuan Lu; Hai Huang

    2012-01-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Mou, Jianye

    2010-10-12T23:59:59.000Z

    distributions and do not consider the contribution of channels to the conductivity. An acid fracture conductivity correlation needs the average fracture width at zero closure stress. Existing correlations calculate average fracture width using dissolved rock...

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

    E-Print Network [OSTI]

    Li, Yingping

    1996-01-01T23:59:59.000Z

    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 ...

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

    E-Print Network [OSTI]

    Plamin, Sammazo Jean-bertrand

    2013-09-29T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Yang, Mei

    2011-10-21T23:59:59.000Z

    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 ...

  20. Degradation of Guar-Based Fracturing Gels: A Study of Oxidative and Enzymatic Breakers

    E-Print Network [OSTI]

    Sarwar, Muhammad Usman

    2012-02-14T23:59:59.000Z

    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...

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

    E-Print Network [OSTI]

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

    2003-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Pearce, Frederick Douglas

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

  3. Fluid escape from reservoirs: implications from cold seeps, fractures and injected sands

    E-Print Network [OSTI]

    Mazzini, Adriano

    Abstract Fluid escape from reservoirs: implications from cold seeps, fractures and injected sands fluids escape from hydrocarbon reservoirs through permeable networks of fractures, injected sands. Within fractures and injected sands, oxidation of chained hydrocarbons supplies bicarbonate to the co

  4. Hydromechanical interactions in a fractured carbonate reservoir inferred from hydraulic and mechanical measurements

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Hydromechanical interactions in a fractured carbonate reservoir inferred from hydraulic, France Abstract Hydromechanical coupled processes in a shallow fractured carbonate reservoir rock were fracture network made up of vertical faults and bedding planes. Hydromechanical response of the reservoir

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

    E-Print Network [OSTI]

    Rodriguez, Erika

    2005-11-01T23:59:59.000Z

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

  6. Prediction and Monitoring Systems of Creep-Fracture Behavior of 9Cr-1Mo Steels for Teactor Pressure Vessels

    SciTech Connect (OSTI)

    Potirniche, Gabriel; Barlow, Fred D.; Charit, Indrajit; Rink, Karl

    2013-11-26T23:59:59.000Z

    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.

  7. Higher-order compositional modeling of three-phase flow in 3D fractured porous media based on cross-flow equilibrium

    E-Print Network [OSTI]

    Firoozabadi, Abbas

    to approximate convective Darcy fluxes and the pressure equa- tion. This approach is the most natural choice for flow in fractured media. The mass balance equations are discretized by the discontinuous Galerkin (DG injection in oil reservoirs that have previously been water flooded. Another example is when gas is injected

  8. UK Oil and Gas Collaborative Doctoral Training Centre (2014 start) Project Title: Coupled flow of water and gas during hydraulic fracture in shale (EARTH-15-CM1)

    E-Print Network [OSTI]

    Henderson, Gideon

    UK Oil and Gas Collaborative Doctoral Training Centre (2014 start) Project Title: Coupled flow of water and gas during hydraulic fracture in shale (EARTH-15-CM1) Host institution: University of Oxford Cartwright Project description: Recovery of natural gas from mudstone (shale) formations has triggered

  9. Patterns and perspectives in applied fracture mechanics

    SciTech Connect (OSTI)

    Merkle, J.G.

    1994-12-31T23:59:59.000Z

    This lecture begins with a overview of applied fracture mechanics pertinent to safety of pressure vessels. It then progresses to a chronological panorama of experimental and analytical results. To be useful and dependable in safety analysis of real structures, new analysis developments must be physically realistic, which means that they must accurately describe physical cause and effect. Consequently, before mathematical modeling can begin, cause and effect must be established from experimental data. This can be difficult and time consuming, but worth the effort. Accordingly, the theme of this paper is that the search for patterns is constant and vital. This theme is illustrated by the development of small, single-specimen, fracture toughness testing techniques. It is also illustrated by the development, based on two different published large-strain, elastic-plastic, three-dimensional finite-element analyses, of a hypothesis concerning three-dimensional loss of constraint. When a generalization of Irwin`s thickness-normalized plastic-zone parameter, reaches a value close to 2{pi}, the through-thickness contraction strain at the apex of the near-tip logarithmic-spiral slip-line region becomes the dominant negative strain accommodating crack opening. Because slip lines passing from the midplane to the stress-free side surfaces do not have to curve, once these slip lines are established, stresses near the crack tip are only elevated by strain hardening and constraint becomes significantly relaxed. This hypothesis, based on published three-dimensional elastic-plastic analyses, provides a potentially valuable means for gaining additional insight into constraint effects on fracture toughness by considering the roles played by the plastic strains as well as the stresses that develop near a crack tip.

  10. Turbulent flow of gas in fractures

    E-Print Network [OSTI]

    Koh, Wong In

    1974-01-01T23:59:59.000Z

    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...

  11. Recent developments in dynamic fracture: Some perspectives

    E-Print Network [OSTI]

    Fineberg, Jay

    2015-01-01T23:59:59.000Z

    We briefly review a number of important recent experimental and theoretical developments in the field of dynamic fracture. Topics include experimental validation of the equations of motion for straight tensile cracks (in both infinite media and strip geometries), validation of a new theoretical description of the near-tip fields of dynamic cracks incorporating weak elastic nonlinearities, a new understanding of dynamic instabilities of tensile cracks in both 2D and 3D, crack front dynamics, and the relation between frictional motion and dynamic shear cracks. Related future research directions are briefly discussed.

  12. Recent developments in dynamic fracture: Some perspectives

    E-Print Network [OSTI]

    Jay Fineberg; Eran Bouchbinder

    2015-04-19T23:59:59.000Z

    We briefly review a number of important recent experimental and theoretical developments in the field of dynamic fracture. Topics include experimental validation of the equations of motion for straight tensile cracks (in both infinite media and strip geometries), validation of a new theoretical description of the near-tip fields of dynamic cracks incorporating weak elastic nonlinearities, a new understanding of dynamic instabilities of tensile cracks in both 2D and 3D, crack front dynamics, and the relation between frictional motion and dynamic shear cracks. Related future research directions are briefly discussed.

  13. 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 onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdf Jump to:ar-80m.pdfFillmoreGabbsSalonga, NewCornersFoxFracture Characterization

  14. Prediction of effects of hydraulic fracturing using reservoir and well flow simulation

    SciTech Connect (OSTI)

    Mineyuki Hanano; Tayuki Kondo

    1992-01-01T23:59:59.000Z

    This paper presents a method to predict and evaluate effects of hydraulic fracturing jobs by using reservoir and well flow numerical simulation. The concept of the method i5 that steam production rate at the operating well head pressure is predicted with different fracture conditions which would be attained by the hydraulic fracturing jobs. Then, the effects of the hydraulic fracturing is evaluated by comparing the predicted steam production rate and that before the hydraulic fracturing. This course of analysis will suggest how large fracture should be created by the fracturing job to attain large enough increase in steam production at the operating condition and the best scheme of the hydraulic fracturing job.

  15. AN INTEGRATED APPROACH TO CHARACTERIZING BYPASSED OIL IN HETEROGENEOUS AND FRACTURED RESERVOIRS USING PARTITIONING TRACERS

    SciTech Connect (OSTI)

    Akhil Datta-Gupta

    2004-08-01T23:59:59.000Z

    We explore the use of efficient streamline-based simulation approaches for modeling and analysis partitioning interwell tracer tests in heterogeneous and fractured hydrocarbon reservoirs. The streamline approach is generalized to model water injection in naturally fractured reservoirs through the use of a dual media approach. The fractures and matrix are treated as separate continua that are connected through a transfer function, as in conventional finite difference simulators for modeling fractured systems. A detailed comparison with a commercial finite difference simulator shows very good agreement. Furthermore, an examination of the scaling behavior of the computation time indicates that the streamline approach is likely to result in significant savings for large-scale field applications. We also propose a novel approach to history matching finite-difference models that combines the advantage of the streamline models with the versatility of finite-difference simulation. In our approach, we utilize the streamline-derived sensitivities to facilitate history matching during finite-difference simulation. The use of finite-difference model allows us to account for detailed process physics and compressibility effects. The approach is very fast and avoids much of the subjective judgments and time-consuming trial-and-errors associated with manual history matching. We demonstrate the power and utility of our approach using a synthetic example and two field examples. Finally, we discuss several alternative ways of using partitioning interwell tracer tests (PITTs) in oil fields for the calculation of oil saturation, swept pore volume and sweep efficiency, and assess the accuracy of such tests under a variety of reservoir conditions.

  16. Edit paper Methods for Large Scale Hydraulic Fracture Monitoring

    E-Print Network [OSTI]

    Ely, Gregory

    2013-01-01T23:59:59.000Z

    In this paper we propose computationally efficient and robust methods for estimating the moment tensor and location of micro-seismic event(s) for large search volumes. Our contribution is two-fold. First, we propose a novel joint-complexity measure, namely the sum of nuclear norms which while imposing sparsity on the number of fractures (locations) over a large spatial volume, also captures the rank-1 nature of the induced wavefield pattern. This wavefield pattern is modeled as the outer-product of the source signature with the amplitude pattern across the receivers from a seismic source. A rank-1 factorization of the estimated wavefield pattern at each location can therefore be used to estimate the seismic moment tensor using the knowledge of the array geometry. In contrast to existing work this approach allows us to drop any other assumption on the source signature. Second, we exploit the recently proposed first-order incremental projection algorithms for a fast and efficient implementation of the resulting...

  17. Transferability of cleavage fracture parameters between notched and cracked geometries

    E-Print Network [OSTI]

    Boyer, Edmond

    and specimen geometry dependence of cleavage fracture micromechanisms of a French pressure vessel steel (A508 that only NT tests with a mean fracture strain lower than 25% have to be considered to make sure ; ¢ 50 £ C ]. Also a unique set of Weibull parameters was found to describe all the NT tests over

  18. Approaching Zero: Using Fractured Crystals in Metrology for Replica Molding

    E-Print Network [OSTI]

    Prentiss, Mara

    and technology.1-6 It is, however, difficult (if not impossible) to fabricate masters below 5 nm using-crystalline silicon wafers (two- or three-inch p- and n-doped silicon wafers with 2-nm layers of native silicon oxide to stabilize and prevent complete fracture of the wafer by dissipating the mechanical energy of fracture

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

    E-Print Network [OSTI]

    Bafia, Daniel Joseph

    1998-01-01T23:59:59.000Z

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

  20. Impact fracture behavior of model system modified polypropylene

    E-Print Network [OSTI]

    Estrada, Albert Jesse

    2000-01-01T23:59:59.000Z

    -edge-notched three-point-bend tests were performed to obtain the values of fracture toughness. A correlation exists between the Izod impact values and the size of the damage zone after fracture. Damage analysis using the double-notch four-point-bend Charpy impact...

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

    E-Print Network [OSTI]

    Jackson, Robert B.

    LETTER Reply to Davies: Hydraulic fracturing remains a possible mechanism for observed methane in aquifers overlying the Marcellus formation but asserts that we prematurely ascribed its cause to hydraulic mechanisms were leaky gas well casings and the possibility that hydraulic fracturing might generate new

  2. CLEAVAGE FRACTURE MICROMECHANISMS RELATED TO WPS EFFECT IN RPV STEEL

    E-Print Network [OSTI]

    Boyer, Edmond

    CLEAVAGE FRACTURE MICROMECHANISMS RELATED TO WPS EFFECT IN RPV STEEL S. R. Bordet1 , B. Tanguy1 , S vessel (RPV) steel. In this purpose, different WPS fracture test results obtained on compact tensile (CT fractographic investigations and finite element (FE) calculations, demonstrate a strong material aspect to WPS

  3. Fracture toughness and process zone kinetics in amorphous polymers

    SciTech Connect (OSTI)

    Kim, A.

    1992-01-01T23:59:59.000Z

    Usually, a process (deformation) zone is formed ahead of a crack as a response to the stress concentration in ductile materials. Then the crack initiation and propagation are inseparable from the evolution of the process zone accompanying the crack. Thus the kinetics of process zone evolution is closely coupled with the time dependency of fracture. In this study, we report the effects of weathering, scale and loading rate on fracture toughness parameters, and the kinetics of process zone evolution. We also propose a kinetic equation for process zone as a basis for modeling of the time dependency of polycarbonate fracture. Since the well-known Griffith's criterion is usually implemented for characterization of brittle fracture, we have reviewed the applicability of the conventional toughness parameter to characterization of brittle polymers. After that we applied the developed experimental and analytical technique to polycarbonate which possesses ductility and thus does not obey the conventional fracture toughness characterization requirements. The fracture toughness analysis leads to recognition of the important role of process zone evolution in fracture phenomena. As result, one of the main topics of the present work is the experimental and theoretical studies of the process zone kinetics. The kinetic equation is derived following the first principle of thermodynamics of irreversible processes. It provides a master curve for the process zone evolution for various initial conditions. The kinetic equation for the evolution of the process zone in polycarbonate is the main achievement of the thesis. The results provide the basis for mathematical modeling of time dependency of fracture.

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

    E-Print Network [OSTI]

    Bafia, Daniel Joseph

    1998-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Awadalla, N.G.

    2001-03-28T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Santos, Juan

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

  7. A Novel Model for Fracture Acidizing with Important Thermal Effects

    E-Print Network [OSTI]

    Lyons, John

    2013-12-05T23:59:59.000Z

    with the formation and the heat generated by acid reaction with the rock) on reaction rate and mass transfer of acid inside the fracture. In this study, a new fracture acidizing model is presented that uses the lattice Boltzmann method for fluid transport...

  8. 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: 612-626-7370 URL: http://www.ima.umn.edu #12;The Effect of Surface Tension in Modeling Interfacial. The proposed model of bi-material crack ascribes curvature-dependent surface tension to both the fracture

  9. Adaptive Methods for Modelling Transport Processes in Fractured Subsurface Systems

    E-Print Network [OSTI]

    Cirpka, Olaf Arie

    ­ discrete Galerkin method applying finite differences for the discretization in time and the StreamlineAdaptive Methods for Modelling Transport Processes in Fractured Subsurface Systems 3rd­adaptive methods for modelling transport processes in fractured rock. As a simplification, ideal tracers

  10. Dynamics of window glass fracture in explosions

    SciTech Connect (OSTI)

    Beauchamp, E.K.; Matalucci, R.V.

    1998-05-01T23:59:59.000Z

    An exploratory study was conducted under the Architectural Surety Program to examine the possibility of modifying fracture of glass in the shock-wave environment associated with terrorist bombings. The intent was to explore strategies to reduce the number and severity of injuries resulting from those attacks. The study consisted of a series of three experiments at the Energetic Materials Research and Testing Center (EMRTC) of the New Mexico Institute of Mining and Technology at Socorro, NM, in which annealed and tempered glass sheets were exposed to blast waves at several different levels of overpressure and specific impulse. A preliminary assessment of the response of tempered glass to the blast environment suggested that inducing early failure would result in lowering fragment velocity as well as reducing the loading from the window to the structure. To test that possibility, two different and novel procedures (indentation flaws and spot annealing) were used to reduce the failure strength of the tempered glass while maintaining its ability to fracture into small cube-shaped fragments. Each experiment involved a comparison of the performance of four sheets of glass with different treatments.

  11. Pressure grouting of fractured basalt flows

    SciTech Connect (OSTI)

    Shaw, P.; Weidner, J.; Phillips, S.; Alexander, J.

    1996-04-01T23:59:59.000Z

    This report describes a field trial of pressure grouting in basalt and the results of subsequent coring and permeability measurement activities. The objective was to show that the hydraulic conductivity of fractured basalt bedrock can be significantly reduced by pressure injection of cementitious materials. The effectiveness of the pressure grout procedure was evaluated by measuring the change in the hydraulic conductivity of the bedrock. The extent of grout penetration was established by analyzing postgrout injection drilling chips for the presence of a tracer in the grout and also by examining cores of the treated basalt. Downhole radar mapping was used to establish major lava flow patterns and follow water movement during a surface infiltration test. A site called Box Canyon, which is located northwest of the INEL, was chosen for this study due to the similarity of this surface outcrop geology to that of the underlying bedrock fracture system found at the Radioactive Waste Management Complex. This study showed that hydraulic conductivity of basalt can be reduced through pressure grouting of cementitious material.

  12. Peri-prosthetic fracture vibration testing

    SciTech Connect (OSTI)

    Cruce, Jesse R [Los Alamos National Laboratory; Erwin, Jenny R [Los Alamos National Laboratory; Remick, Kevin R [Los Alamos National Laboratory; Cornwell, Phillip J [Los Alamos National Laboratory; Menegini, R. Michael [INDIANA UNIV.; Racanelli, Joe [STRYKER ORTHOPAEDICS

    2011-01-28T23:59:59.000Z

    The purpose of this study is to establish a test setup and vibration analysis method to predict femoral stem seating and prevent bone fracture using accelerometer or force response data from an instrument stem and impactor. This study builds upon earlier studies to identify a means to supplement a surgeon's tactile and auditory senses by using damage identification techniques normally used for civil and mechanical structures. Testing will be conducted using foam cortical shell sawbones prepared for stems of different geometries. Each stem will be instrumented with an accelerometer. Two impactor designs will be compared: a monolithic impactor with an integrated load cell and accelerometer and a two piece impactor. Acceleration and force measurements will be taken in the direction of impaction. Signal processing techniques will be applied to the acceleration time histories to determine features that can be used to assess device seating and potential fracture. A consistent energy input will be applied using a drop tower. The effect of introducing compliance under the bone support vise will also be investigated. The ultimate goal of this study is to design an integrated portable data acquisition system capable of being used in future cadaveric testing. This paper will discuss the experimental set-up, the signal processing techniques used and the subsequent results.

  13. Fracture and Fragmentation of Simplicial Finite Elements Meshes using Graphs

    SciTech Connect (OSTI)

    Mota, A; Knap, J; Ortiz, M

    2006-10-18T23:59:59.000Z

    An approach for the topological representation of simplicial finite element meshes as graphs is presented. It is shown that by using a graph, the topological changes induced by fracture reduce to a few, local kernel operations. The performance of the graph representation is demonstrated and analyzed, using as reference the 3D fracture algorithm by Pandolfi and Ortiz [22]. It is shown that the graph representation initializes in O(N{sub E}{sup 1.1}) time and fractures in O(N{sub I}{sup 1.0}) time, while the reference implementation requires O(N{sub E}{sup 2.1}) time to initialize and O(N{sub I}{sup 1.9}) time to fracture, where NE is the number of elements in the mesh and N{sub I} is the number of interfaces to fracture.

  14. From invasion percolation to flow in rock fracture networks

    E-Print Network [OSTI]

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

    2011-01-01T23:59:59.000Z

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

  15. Enthalpy transients in fractured two-phase geothermal systems

    SciTech Connect (OSTI)

    Lippmann, M.J.; Bodvarsson, G.S.; Gaulke, S.W.

    1985-03-01T23:59:59.000Z

    Numerical modeling techniques are used to study the changes in flowing enthalpy of fluids produced from a well completed in a fractured two-phase geothermal reservoir. Complex interactions between different fracture and porous matrix parameters control the enthalpy transients. The results show that the flowing enthalpy is most sensitive to the characteristics of the relative permeability curves, the magnitude of the matrix permeability and the effective fracture porosity. Other parameters such as the thermal conductivity and fracture spacing also significantly affect the flowing enthalpy. In spite of the complex phenomena associated with enthalpy transients in fractured two-phase systems, it is possible to infer useful information about the producing geothermal reservoirs from field data. 15 refs., 13 figs., 2 tabs.

  16. Natural gas product and strategic analysis

    SciTech Connect (OSTI)

    Layne, A.W.; Duda, J.R.; Zammerilli, A.M.

    1993-12-31T23:59:59.000Z

    Product and strategic analysis at the Department of Energy (DOE)/Morgantown Energy Technology Center (METC) crosscuts all sectors of the natural gas industry. This includes the supply, transportation, and end-use sectors of the natural-gas market. Projects in the Natural Gas Resource and Extraction supply program have been integrated into a new product focus. Product development facilitates commercialization and technology transfer through DOE/industry cost-shared research, development, and demonstration (RD&D). Four products under the Resource and Extraction program include Resource and Reserves; Low Permeability Formations; Drilling, Completion, and Stimulation: and Natural Gas Upgrading. Engineering process analyses have been performed for the Slant Hole Completion Test project. These analyses focused on evaluation of horizontal-well recovery potential and applications of slant-hole technology. Figures 2 and 3 depict slant-well in situ stress conditions and hydraulic fracture configurations. Figure 4 presents Paludal Formation coal-gas production curves used to optimize the hydraulic fracture design for the slant well. Economic analyses have utilized data generated from vertical test wells to evaluate the profitability of horizontal technology for low-permeability formations in Yuma County, Colorado, and Maverick County, Texas.

  17. Mimicking Nature

    E-Print Network [OSTI]

    Wythe, Kathy

    2007-01-01T23:59:59.000Z

    into lakes and rivers, and the impact different water management decisions could have. ?We?re trying to mimic nature,? said Dr. Jeff Arnold, research leader and agricultural engineer for the Grassland Soil and Water Research Laboratory in Temple, part..., director of Texas A&M University?s Spatial Sciences Laboratory and professor in the Departments of Ecosystem Science and MIMICKING NATURE Computer model helps manage nation?s, world?s waters #2; Management, and Biological and Agricultural Engineering...

  18. Naturalness redux

    E-Print Network [OSTI]

    Marco Fabbrichesi; Alfredo Urbano

    2015-04-21T23:59:59.000Z

    The idea of naturalness, as originally conceived, refers only to the finite renormalization of the Higgs boson mass induced by the introduction of heavier states. In this respect, naturalness is still a powerful heuristic principle in model building beyond the standard model whenever new massive states are coupled to the Higgs field. The most compelling case is provided by the generation of neutrino masses. In this paper we confront this problem from a new perspective. The right-handed sector responsible for the seesaw mechanism---which introduces a large energy threshold above the electroweak scale---is made supersymmetric to comply with naturalness while the standard model is left unchanged and non-supersymmetric. Cancellations necessary to the naturalness requirement break down only at two loops, thus offering the possibility to increase the right-handed neutrino mass scale up to one order of magnitude above the usual values allowed by naturalness. If also the weak boson sector of the standard model is made supersymmetric, cancellations break down at three loops and the scale of new physics can be further raised. In the type-I seesaw, this implementation provides right-handed neutrino masses that are natural and at the same time large enough to give rise to baryogenesis (via leptogenesis). The model contains a dark matter candidate and distinctive new physics in the leptonic sector.

  19. REAL-TIME ACTIVE PIPELINE INTEGRITY DETECTION (RAPID) SYSTEM FOR CORROSION DETECTION AND QUANTIFICATION

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    alone there are over 2 million miles of natural gas transmission and distribution pipeline providing 24REAL-TIME ACTIVE PIPELINE INTEGRITY DETECTION (RAPID) SYSTEM FOR CORROSION DETECTION detection Acellent has developed a Real-time Active Pipeline Integrity Detection (RAPID) system. The RAPID

  20. Seismic waves in rocks with fluids and fractures

    SciTech Connect (OSTI)

    Berryman, J.G.

    2007-05-14T23:59:59.000Z

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

  1. Fractured reservoir evaluation using Monte Carlo techniques

    SciTech Connect (OSTI)

    Sears, G.F.; Phillips, N.V.

    1987-01-01T23:59:59.000Z

    Pro forma cash-flow analysis of petroleum ventures usually is considered as a deterministic model. In the last 10 years, Monte Carlo analysis has allowed the introduction of probability distributions of input variables in place of single-valued functions. Reserve determination and rate scheduling in these current Monte Carlo techniques have relied on the volumetric formula, which works well in nonfractured reservoirs. Recent massive drilling in fractured reservoirs has rendered this approach unusable. This paper develops a variation of the Arps rate-cumulative equation as a basic model for the determination of the distribution of original reserves and the decline rates. Continuation of the Monte Carlo technique into net present value analysis and internal rate of return (IRR) is also developed.

  2. Fracture toughness for copper oxide superconductors

    DOE Patents [OSTI]

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

    1993-04-13T23:59:59.000Z

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

  3. Fracture toughness for copper oxide superconductors

    DOE Patents [OSTI]

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

    1993-01-01T23:59:59.000Z

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

  4. 2006 GeoX Conference, pages 1 to 6 Characterisation of hydraulic fractures in

    E-Print Network [OSTI]

    2006 GeoX Conference, pages 1 to 6 Characterisation of hydraulic fractures in limestones using X, France Jacques.Desrues@hmg.inpg.fr ABSTRACT: Hydraulic tension fractures were produced in porous, hydraulic fracture, permeability tensor MOTS-CLÃ?S: microtomographie, fracturation hydraulique, tenseur de

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

    E-Print Network [OSTI]

    Peirce, Anthony

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

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

    E-Print Network [OSTI]

    Yang, Mei

    2011-10-21T23:59:59.000Z

    -layered reservoir, (3) The upwards and downwards growth of the fracture tip from the crack center....

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

    Broader source: Energy.gov [DOE]

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

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

    E-Print Network [OSTI]

    Henderson, Gideon

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

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

    E-Print Network [OSTI]

    Santos, Juan

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

  10. A mixed-dimensional finite volume method for two-phase flow in fractured porous media

    E-Print Network [OSTI]

    Bastian, Peter

    . Key words: Multiphase flow; Numerical reservoir simulation; Fractured reservoir; MixedA mixed-dimensional finite volume method for two-phase flow in fractured porous media Volker-phase flow in fractured porous media. Fractures are dis- cretely modeled as lower dimensional elements

  11. Natural Predator

    E-Print Network [OSTI]

    Wythe, Kathy

    2006-01-01T23:59:59.000Z

    tx H2O | pg. 10 Natural Predator Story by Kathy Wythe Natural Predator Foreign beetle shows promise for controlling saltcedar In the northern part of the Texas Panhandle andalong the West Texas banks of the Colorado andPecos rivers, Texas... scientists are successfully intro- ducing a foreign beetle to help control an invasive and exotic water-thirsty plant. Saltcedar, or Tamarix, was introduced to the western United States in the 1800s from central Asia as an ornamental tree and planted...

  12. FIELD-SCALE EFFECTIVE MATRIX DIFFUSION COEFFICIENT FOR FRACTURED ROCK:RESULTS FROM LITERATURE SURVEY

    SciTech Connect (OSTI)

    Q. Zhou; Hui-Hai Liu; F.J. Molz; Y. Zhang; G.S. Bodvarsson

    2005-04-08T23:59:59.000Z

    Matrix diffusion is an important mechanism for solute transport in fractured rock. We recently conducted a literature survey on the effective matrix diffusion coefficient, D{sub m}{sup e}, a key parameter for describing matrix diffusion processes at the field scale. Forty field tracer tests at 15 fractured geologic sites were surveyed and selected for the study, based on data availability and quality. Field-scale D{sub m}{sup e} values were calculated, either directly using data reported in the literature or by reanalyzing the corresponding field tracer tests. Surveyed data indicate that the effective-matrix-diffusion-coefficient factor F{sub D} (defined as the ratio of D{sub m}{sup e} to the lab-scale matrix diffusion coefficient [D{sub m}] of the same tracer) is generally larger than one, indicating that the effective matrix diffusion coefficient in the field is comparatively larger than the matrix diffusion coefficient at the rock-core scale. This larger value can be attributed to the many mass-transfer processes at different scales in naturally heterogeneous, fractured rock systems. Furthermore, we observed a moderate trend toward systematic increase in the F{sub D} value with observation scale, indicating that the effective matrix diffusion coefficient is likely to be statistically scale dependent. The F{sub D} value ranges from 1 to 10,000 for observation scales from 5 to 2,000 m. At a given scale, the F{sub D} value varies by two orders of magnitude, reflecting the influence of differing degrees of fractured rock heterogeneity at different sites. In addition, the surveyed data indicate that field-scale longitudinal dispersivity generally increases with observation scale, which is consistent with previous studies. The scale-dependent field-scale matrix diffusion coefficient (and dispersivity) may have significant implications for assessing long-term, large-scale radionuclide and contaminant transport events in fractured rock, both for nuclear waste disposal and contaminant remediation.

  13. Performance of petroleum reservoirs containing random vertical fractures 

    E-Print Network [OSTI]

    Huskey, William Lyman

    1963-01-01T23:59:59.000Z

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

  14. Measurement of induced fractures by downhole TV camera in Black Warrior Basin coalbeds

    SciTech Connect (OSTI)

    Palmer, I.D. (Amoco Production Co., Tulsa, OK (US)); Sparks, P. (Taurus Exploration Inc., Birmingham, AL (US))

    1991-03-01T23:59:59.000Z

    Fracture stimulation is commonly used for coal degasification at the Black Warrior basin in Alabama. To understand coalbed fracturing better, Well AM-1 in the Oak Grove field was completed openhole in the section bracketing the Black Creek coals. Special diagnostics used on this project included various injection tests, static-line pressure measurements, and a downhole television camera. The television camera observed fractures during injection tests and after the propped fracture treatment. The authors believe these are the first successful downhole television pictures of propped fractures in coalbeds. Results are compared with predictions of hydraulic fracture simulators. This is a way of calibrating hydraulic fracture models for improved design/optimization.

  15. Multi-scale approach to invasion percolation of rock fracture networks

    E-Print Network [OSTI]

    Ali N. Ebrahimi; Falk K. Wittel; Nuno A. M. Araújo; Hans J. Herrmann

    2014-08-12T23:59:59.000Z

    A multi-scale scheme for the invasion percolation of rock fracture networks with heterogeneous fracture aperture fields is proposed. Inside fractures, fluid transport is calculated on the finest scale and found to be localized in channels as a consequence of the aperture field. The channel network is characterized and reduced to a vectorized artificial channel network (ACN). Different realizations of ACNs are used to systematically calculate efficient apertures for fluid transport inside differently sized fractures as well as fracture intersection and entry properties. Typical situations in fracture networks are parameterized by fracture inclination, flow path length along the fracture and intersection lengths in the entrance and outlet zones of fractures. Using these scaling relations obtained from the finer scales, we simulate the invasion process of immiscible fluids into saturated discrete fracture networks, which were studied in previous works.

  16. assess fracture healing: Topics by E-print Network

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

    Cake after Static Build Up and Shear Erosion Texas A&M University - TxSpace Summary: The hydraulic fracturing treatment is an essential tight sand gas reservoir stimulation that...

  17. accelerates fracture healing: Topics by E-print Network

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

    Cake after Static Build Up and Shear Erosion Texas A&M University - TxSpace Summary: The hydraulic fracturing treatment is an essential tight sand gas reservoir stimulation that...

  18. acute rib fracture: Topics by E-print Network

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

    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...

  19. acute avulsion fractures: Topics by E-print Network

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

    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...

  20. apparent interfacial fracture: Topics by E-print Network

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

    (more) Singh, Hitendra Kumar 2005-01-01 10 Mathematical modeling of a CO?b2?s-enriched waterflood in fractured reservoirs Texas A&M University - TxSpace Summary: . . . . . . . 2...