National Library of Energy BETA

Sample records for faults fractures lithology

  1. The effects of lithology and initial fault angle in physical models of fault-propagation folds 

    E-Print Network [OSTI]

    McLain, Christopher Thomas

    2001-01-01

    with a weak brittle layer that deforms by faulting and fracturing (dried pottery clay simulates an interbedded siliciclastic unit). The models were deformed in a triaxial deformation rig at confining pressure of 50 Mpa at room temperature. Each model...

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

    E-Print Network [OSTI]

    Chester, Frederick M.

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

  3. Collateral damage: Evolution with displacement of fracture distribution and secondary fault strands in fault

    E-Print Network [OSTI]

    Savage, Heather M.

    Collateral damage: Evolution with displacement of fracture distribution and secondary fault strands in fault damage zones Heather M. Savage1,2 and Emily E. Brodsky1 Received 22 April 2010; revised 10 of fracture distributions as a function of displacement to determine whether damage around small and large

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

    E-Print Network [OSTI]

    Yang, Mei

    2011-10-21

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

  5. NUMERICAL PREDICTION OF FAULTING AND FRACTURING IN THE AHNET BASIN, ALGERIA

    E-Print Network [OSTI]

    Beekman, Fred

    1 NUMERICAL PREDICTION OF FAULTING AND FRACTURING IN THE AHNET BASIN, ALGERIA Fred Beekman1 and natural fractures strongly depends on the material properties and on the structural position inside models predict rock fracturing to be initiated at shallow depths at the crest of the anticline, and under

  6. Scales Depencence of Fracture Density and Fabric in the Damage Zone of a Large Displacement Continental Transform Fault 

    E-Print Network [OSTI]

    Ayyildiz, Muhammed

    2012-08-28

    Characterization of fractures in an arkosic sandstone from the western damage zone of the San Andreas Fault (SAF) at San Andreas Fault Observatory at Depth (SAFOD) was used to better understand the origin of damage and to determine the scale...

  7. Collateral damage: Evolution with displacement of fracture distribution and secondary fault strands in fault damage zones

    E-Print Network [OSTI]

    Savage, Heather M.; Brodsky, Emily E.

    2011-01-01

    E. McCallum (1999), Reservoir damage around faults: OutcropSkar (2005), Controls on damage zone asymmetry of a normal2007), The evolution of the damage zone with fault growth in

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

    E-Print Network [OSTI]

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

  9. Unsaturated flow and transport through a fault embedded in fractured welded tuff

    E-Print Network [OSTI]

    Hu, Qinhong "Max"

    in locations where there is environmental contamination or the poten- tial for disposal of radioactive waste [Native et al., 1995], and the proposed radioactive waste repository in the tuff forma- tions at YuccaUnsaturated flow and transport through a fault embedded in fractured welded tuff Rohit Salve, Hui

  10. Area balance and strain in an extensional fault system: Strategies for improved oil recovery in fractured chalk, Gilbertown Field, southwestern Alabama. Annual report, March 1996--March 1997

    SciTech Connect (OSTI)

    Pashin, J.C.; Raymond, D.E.; Rindsberg, A.K.; Alabi, G.G.; Groshong, R.H.

    1997-08-01

    Gilbertown Field is the oldest oil field in Alabama and produces oil from chalk of the Upper Cretaceous Selma Group and from sandstone of the Eutaw Formation along the southern margin of the Gilbertown fault system. Most of the field has been in primary recovery since establishment, but production has declined to marginally economic levels. This investigation applies advanced geologic concepts designed to aid implementation of improved recovery programs. The Gilbertown fault system is detached at the base of Jurassic salt. The fault system began forming as a half graben and evolved in to a full graben by the Late Cretaceous. Conventional trapping mechanisms are effective in Eutaw sandstone, whereas oil in Selma chalk is trapped in faults and fault-related fractures. Burial modeling establishes that the subsidence history of the Gilbertown area is typical of extensional basins and includes a major component of sediment loading and compaction. Surface mapping and fracture analysis indicate that faults offset strata as young as Miocene and that joints may be related to regional uplift postdating fault movement. Preliminary balanced structural models of the Gilbertown fault system indicate that synsedimentary growth factors need to be incorporated into the basic equations of area balance to model strain and predict fractures in Selma and Eutaw reservoirs.

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

    E-Print Network [OSTI]

    McKenzie, Jeffrey M.

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

  12. Area balance and strain in an extensional fault system: Strategies for improved oil recovery in fractured chalk, Gilbertown Field, southwestern Alabama. Final report, March 1996--September 1998

    SciTech Connect (OSTI)

    Pashin, J.C.; Raymond, D.E.; Rindsberg, A.K.; Alabi, G.G.; Carroll, R.E.; Groshong, R.H.; Jin, G.

    1998-12-01

    This project was designed to analyze the structure of Mesozoic and Tertiary strata in Gilbertown Field and adjacent areas to suggest ways in which oil recovery can be improved. The Eutaw Formation comprises 7 major flow units and is dominated by low-resistivity, low-contrast play that is difficult to characterize quantitatively. Selma chalk produces strictly from fault-related fractures that were mineralized as warm fluid migrated from deep sources. Resistivity, dipmeter, and fracture identification logs corroborate that deformation is concentrated in the hanging-wall drag zones. New area balancing techniques were developed to characterize growth strata and confirm that strain is concentrated in hanging-wall drag zones. Curvature analysis indicates that the faults contain numerous fault bends that influence fracture distribution. Eutaw oil is produced strictly from footwall uplifts, whereas Selma oil is produced from fault-related fractures. Clay smear and mineralization may be significant trapping mechanisms in the Eutaw Formation. The critical seal for Selma reservoirs, by contrast, is where Tertiary clay in the hanging wall is juxtaposed with poorly fractured Selma chalk in the footwall. Gilbertown Field can be revitalized by infill drilling and recompletion of existing wells. Directional drilling may be a viable technique for recovering untapped oil from Selma chalk. Revitalization is now underway, and the first new production wells since 1985 are being drilled in the western part of the field.

  13. Mesoscale fracture fabric and paleostress along the San Andreas fault at SAFOD 

    E-Print Network [OSTI]

    Almeida, Rafael Vladimir

    2009-05-15

    Spot cores from Phase 1 drilling of the main borehole at the San Andreas Fault Observatory at Depth (SAFOD) were mapped to characterize the mesoscale structure and infer paleostress at depth. Cores were oriented by comparing ...

  14. Finite-difference modeling of faults and fractures Richard T. Coates ...

    E-Print Network [OSTI]

    2010-06-09

    For the purposes of seismic propagation, a slip fault may be regarded ..... -200. 0. 200 400 offset [m]. (b). Upper Receiver Array. Oil. 0.05. 0.1. 0.15. 0.2. 0.25. 0.3.

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

    E-Print Network [OSTI]

    % of their initial concentration in the shale, indicating that the impact on groundwater quality could be significant potentially conductive faults, and that impacts should be monitored for long timespans. Further work is needed to assess the impact of multiphase flow on contaminant transport along natural preferential pathways

  16. Seismoelectric Imaging of a Shallow Fault System Employing Fault Guided Waves 

    E-Print Network [OSTI]

    Cohrs, Frelynn Joseph Reese

    2012-07-16

    . The seismic data revealed dispersive energy packets, indicative of guided waves, within the fault zone and absent in the surrounding lithologies. The seismoelectric data was able to produce comparable signals in the fault zone showing guided waves....

  17. Evaluation of the location and recency of faulting near prospective surface facilities in Midway Valley, Nye County, Nevada

    SciTech Connect (OSTI)

    Swan, F.H.; Wesling, J.R.; Angell, M.M.; Thomas, A.P.; Whitney, J.W.; Gibson, J.D.

    2002-01-17

    Evaluation of surface faulting that may pose a hazard to prospective surface facilities is an important element of the tectonic studies for the potential Yucca Mountain high-level radioactive waste repository in southwestern Nevada. For this purpose, a program of detailed geologic mapping and trenching was done to obtain surface and near-surface geologic data that are essential for determining the location and recency of faults at a prospective surface-facilities site located east of Exile Hill in Midway Valley, near the eastern base of Yucca Mountain. The dominant tectonic features in the Midway Valley area are the north- to northeast-trending, west-dipping normal faults that bound the Midway Valley structural block-the Bow Ridge fault on the west side of Exile Hill and the Paint-brush Canyon fault on the east side of the valley. Trenching of Quaternary sediments has exposed evidence of displacements, which demonstrate that these block-bounding faults repeatedly ruptured the surface during the middle to late Quaternary. Geologic mapping, subsurface borehole and geophysical data, and the results of trenching activities indicate the presence of north- to northeast-trending faults and northwest-trending faults in Tertiary volcanic rocks beneath alluvial and colluvial sediments near the prospective surface-facilities site. North to northeast-trending faults include the Exile Hill fault along the eastern base of Exile Hill and faults to the east beneath the surficial deposits of Midway Valley. These faults have no geomorphic expression, but two north- to northeast-trending zones of fractures exposed in excavated profiles of middle to late Pleistocene deposits at the prospective surface-facilities site appear to be associated with these faults. Northwest-trending faults include the West Portal and East Portal faults, but no disruption of Quaternary deposits by these faults is evident. The western zone of fractures is associated with the Exile Hill fault. The eastern zone of fractures is within Quaternary alluvial sediments, but no bedrock was encountered in trenches and soil pits in this part of the prospective surface facilities site; thus, the direct association of this zone with one or more bedrock faults is uncertain. No displacement of lithologic contacts and soil horizons could be detected in the fractured Quaternary deposits. The results of these investigations imply the absence of any appreciable late Quaternary faulting activity at the prospective surface-facilities site.

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

    Open Energy Info (EERE)

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

  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

    2013-07-01

    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. Stress and fault rock controls on fault zone hydrology, Coso...

    Open Energy Info (EERE)

    fault zone hydrology, Coso geothermal field, CA Abstract In crystalline rock of the Coso Geothermal Field, CA, fractures are the primary source of permeability. At reservoir...

  1. Method development and strategy for the characterization of complexly faulted and fractured rhyolitic tuffs, Yucca Mountain, Nevada

    SciTech Connect (OSTI)

    Karasaki, K. [Lawrence Berkeley Lab., CA (United States); Galloway, D. [Geological Survey, Sacramento, CA (United States)

    1991-06-01

    The planned high-level nuclear waste repository at Yucca Mountain, Nevada, would exist in unsaturated, fractured welded tuff. One possible contaminant pathway to the accessible environment is transport by groundwater infiltrating to the water table and flowing through the saturated zone. Therefore, an effort to characterize the hydrology of the saturated zone is being undertaken in parallel with that of the unsaturated zone. As a part of the saturated zone investigation, there wells-UE-25c{number_sign}1, UE-25c{number_sign}2, and UE-25c{number_sign}3 (hereafter called the c-holes)-were drilled to study hydraulic and transport properties of rock formations underlying the planned waste repository. The location of the c-holes is such that the formations penetrated in the unsaturated zone occur at similar depths and with similar thicknesses as at the planned repository site. In characterizing a highly heterogeneous flow system, several issues emerge. (1) The characterization strategy should allow for the virtual impossibility to enumerate and characterize all heterogeneities. (2) The methodology to characterize the heterogeneous flow system at the scale of the well tests needs to be established. (3) Tools need to be developed for scaling up the information obtained at the well-test scale to the larger scale of the site. In the present paper, the characterization strategy and the methods under development are discussed with the focus on the design and analysis of the field experiments at the c-holes.

  2. Motion and evolution of the Chaochou Fault, Southern Taiwan 

    E-Print Network [OSTI]

    Hassler, Lauren E.

    2005-11-01

    The Chaochou Fault (CCF) is both an important lithologic boundary and a significant topographic feature in the Taiwan orogenic belt. It is the geologic boundary between the Slate Belt to the east, and the Western Foothills to the west. Although...

  3. Deep drilling phase of the Pen Brand Fault Program

    SciTech Connect (OSTI)

    Stieve, A.

    1991-05-15

    This deep drilling activity is one element of the Pen Branch Fault Program at Savannah River Site (SRS). The effort will consist of three tasks: the extension of wells PBF-7 and PBF-8 into crystalline basement, geologic and drilling oversight during drilling operations, and the lithologic description and analysis of the recovered core. The drilling program addresses the association of the Pen Branch fault with order fault systems such as the fault that formed the Bunbarton basin in the Triassic.

  4. Core Lithology State of Hawail Scientific Observation Hole 2...

    Open Energy Info (EERE)

    Core Lithology State of Hawail Scientific Observation Hole 2 Kilauea Volcano, Hawaii Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Core Lithology State...

  5. Core Lithology State of Hawaii Scientific Observation Hole 4...

    Open Energy Info (EERE)

    Core Lithology State of Hawaii Scientific Observation Hole 4 Kilauea Volcano, Hawaii Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Core Lithology State...

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

    Open Energy Info (EERE)

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

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

    Open Energy Info (EERE)

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

  8. The effect of fractures, faults, and sheared shale zones on the hydrology of Bear Creek Burial Grounds A-South, Oak Ridge, Tennessee 

    E-Print Network [OSTI]

    Hollon, Dwight Mitchell

    1997-01-01

    in the Maynardville Limestone do not appear to be caused by dissolution; instead, they appear to be the result of a change in the local stress field due to erosion effects. Faults, both cross-valley and thrust faults, and sheared shale zones are interpreted...

  9. Fluids migration and dynamics of a blocks-and-faults system

    E-Print Network [OSTI]

    1910-70-11

    Keywords: earthquake catalog, block model, fault, tectonic structure, fluid, fil- ...... nal vertical fault near upper vertices of adjacent internal blocks, and formation of ... acts near the right external vertical fault: fractures filled in with water emerge ...

  10. ADVANCED CHARACTERIZATION OF FRACTURED RESERVOIRS IN CARBONATE ROCKS: THE MICHIGAN BASIN

    SciTech Connect (OSTI)

    James R. Wood; William B. Harrison

    2002-12-01

    The purpose of the study was to collect and analyze existing data on the Michigan Basin for fracture patterns on scales ranging form thin section to basin. The data acquisition phase has been successfully concluded with the compilation of several large digital databases containing nearly all the existing information on formation tops, lithology and hydrocarbon production over the entire Michigan Basin. These databases represent the cumulative result of over 80 years of drilling and exploration. Plotting and examination of these data show that contrary to most depictions, the Michigan Basin is in fact extensively faulted and fractured, particularly in the central portion of the basin. This is in contrast to most of the existing work on the Michigan Basin, which tends to show relatively simple structure with few or minor faults. It also appears that these fractures and faults control the Paleozoic sediment deposition, the subsequent hydrocarbon traps and very likely the regional dolomitization patterns. Recent work has revealed that a detailed fracture pattern exists in the interior of the Central Michigan Basin, which is related to the mid-continent gravity high. The inference is that early Precambrian, ({approx}1 Ga) rifting events presumed by many to account for the gravity anomaly subsequently controlled Paleozoic sedimentation and later hydrocarbon accumulation. There is a systematic relationship between the faults and a number of gas and oil reservoirs: major hydrocarbon accumulations consistently occur in small anticlines on the upthrown side of the faults. The main tools used in this study to map the fault/fracture patterns are detailed, close-interval (CI = 10 feet) contouring of the formation top picks accompanied by a new way of visualizing the data using a special color spectrum to bring out the third dimension. In addition, recent improvements in visualization and contouring software were instrumental in the study. Dolomitization is common in the Michigan Basin, and it is crucial in developing reservoir quality rocks in some fields. Data on the occurrence of dolomite was extracted from driller's reports for all reported occurrences in Michigan, nearly 50 fields and over 500 wells. A digital database was developed containing the geographic location of all these wells (latitude-longitude) as well as the elevation of the first encounter of dolomite in the field/reservoir. Analysis shows that these dolomite occurrences are largely confined to the center of the basin, but with some exceptions, such as N. Adams Field. Further, some of the dolomite occurrences show a definite relationship to the fracture pattern described above, suggesting a genetic relationship that needs further work. Other accomplishments of this past reporting period include obtaining a complete land grid for the State of Michigan and further processing of the high and medium resolution DEM files. We also have measured new fluid inclusion data on dolomites from several fields that suggest that the dolomitization occurred at temperatures between 100 and 150 C. Finally, we have extracted the lithologic data for about 5000 wells and are in the process of integrating this data into the overall model for the Michigan Basin.

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

    E-Print Network [OSTI]

    Bafia, Daniel Joseph

    1998-01-01

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

  12. Core Lithology From the State of Hawaii Scientific Observation...

    Open Energy Info (EERE)

    Core Lithology From the State of Hawaii Scientific Observation Hole 1, Kilauea Volcano, Hawaii Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Core...

  13. Fault finder

    DOE Patents [OSTI]

    Bunch, Richard H. (1614 NW. 106th St., Vancouver, WA 98665)

    1986-01-01

    A fault finder for locating faults along a high voltage electrical transmission line. Real time monitoring of background noise and improved filtering of input signals is used to identify the occurrence of a fault. A fault is detected at both a master and remote unit spaced along the line. A master clock synchronizes operation of a similar clock at the remote unit. Both units include modulator and demodulator circuits for transmission of clock signals and data. All data is received at the master unit for processing to determine an accurate fault distance calculation.

  14. Neural network analysis of sparse datasets ?? an application to the fracture system in folds of the Lisburne Formation, northeastern Alaska 

    E-Print Network [OSTI]

    Bui, Thang Dinh

    2005-11-01

    with conventional statistical analysis, were used to examine the effects of folding, bed thickness, structural position, and lithology on the fracture properties distributions in the Lisburne Formation, folded and exposed in the northeastern Brooks Range of Alaska...

  15. Effects of burial history, rock ductility and recovery magnitude on inversion of normal faulted strata 

    E-Print Network [OSTI]

    Kuhle, Nathan John

    2001-01-01

    , and distributed fracturing and folding. The relative contribution of these mechanisms depends on the relative ductility of the rock and magnitude of inversion. Reverse slip on the normal fault and distributed fracturing occur during early stages of inversion...

  16. Geomechanical Simulation of Fluid-Driven Fractures

    SciTech Connect (OSTI)

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

    2012-11-30

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

  17. Vp-Vs ratio sensitivity to pressure, fluid, and lithology changes in tight gas sandstones Eugenia Rojas*, Thomas L. Davis, Michael Batzle, Manika Prasad, Colorado School of Mines, Golden, CO,

    E-Print Network [OSTI]

    in prospect identification in tight gas sandstone reservoirs, because they are related to good quality rocks and permeability, possible presence of natural fractures, uncertainty in gas/water contact and high possibilityVp-Vs ratio sensitivity to pressure, fluid, and lithology changes in tight gas sandstones Eugenia

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

    E-Print Network [OSTI]

    Ramsey, Jonathan Michael

    2003-01-01

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

  19. Microscopic feather fractures in the faulting process 

    E-Print Network [OSTI]

    Conrad, Robert Eugene

    1974-01-01

    to a similar siesmic study, stopped triaxial compression tests at 10 various stages prior to failure and analyzed the microfractures in thin section. They found the early microfractures to be oriented within 30' of the load axis, and that they tend... similar, but their percentages of microfractures of a given orientation agree with those for Mff determined here. The question remains does the local maximum compression axis parallel the observed orientation of Mff, Given an end-loaded cylinder...

  20. Lithology and well log study of Campbell E-2 geothermal test...

    Open Energy Info (EERE)

    Lithology and well log study of Campbell E-2 geothermal test well, Humboldt House geothermal prospect, Pershing County, Nevada Jump to: navigation, search OpenEI Reference...

  1. Dynamic leakage of faults during differential depletion: Theory, models, and examples from the Niger delta

    SciTech Connect (OSTI)

    Watts, N.L.; Kaars Sijpestein, C.H.; Osai, L.N.; Okoli, O.C. (Shell Petroleum Development Co. of Nigeria, Lagos (Nigeria))

    1991-08-01

    Previous studies of fault sealing have addressed possible fault leakage during secondary migration due to the effects of increased hydrocarbon-water capillary pressure, fracturing, or small-scale incremental fault movements. Of equal importance to production geologists is the failure and leakage of faults during field development due to differential depletion of adjacent fault blocks. This paper examines the unique problems associated with this dynamic leakage of faults. It is theoretically shown that the fault sealing mechanism, and the extent of the seal, directly influences the failure process which in turn results in a variety of favorable and unfavorable effects on field development. The qualitative models give considerable insight into such aspects as oil-column expansion and resaturation losses, interfault block aquifer support (with important implications to material balance calculations), possible leakage or spillage of oil across faults, and potential fault failure during (re)injection projects. Examples of dynamic fault leakage are presented from selected fields of the Niger delta.

  2. Feature Detection, Characterization and Confirmation Methodology: Final Report

    E-Print Network [OSTI]

    Karasaki, Kenzi

    2009-01-01

    of vertical borehole flow. The geothermal gradient is thegeothermal temperature gradient that is consistent with temperature profiles observed in boreholesgeothermal gradient) Fracture, porosity, lithology Velocity of intact granite, faults and fracture zone fractures, continuity and geometry of features between boreholes

  3. Review article Induced seismicity and hydraulic fracturing for the recovery of

    E-Print Network [OSTI]

    Foulger, G. R.

    Review article Induced seismicity and hydraulic fracturing for the recovery of hydrocarbons Richard mining (M 1.0e5.2); (h) geothermal operations (M 1.0e4.6) and (i) hydraulic fracturing for recovery seismicity occurs due to a reduction in effective stress on fault planes. Hydraulic fracturing operations can

  4. Heterogeneous slip and rupture models of the San Andreas fault zone based upon three-dimensional earthquake tomography

    SciTech Connect (OSTI)

    Foxall, W.

    1992-11-01

    Crystal fault zones exhibit spatially heterogeneous slip behavior at all scales, slip being partitioned between stable frictional sliding, or fault creep, and unstable earthquake rupture. An understanding the mechanisms underlying slip segmentation is fundamental to research into fault dynamics and the physics of earthquake generation. This thesis investigates the influence that large-scale along-strike heterogeneity in fault zone lithology has on slip segmentation. Large-scale transitions from the stable block sliding of the Central 4D Creeping Section of the San Andreas, fault to the locked 1906 and 1857 earthquake segments takes place along the Loma Prieta and Parkfield sections of the fault, respectively, the transitions being accomplished in part by the generation of earthquakes in the magnitude range 6 (Parkfield) to 7 (Loma Prieta). Information on sub-surface lithology interpreted from the Loma Prieta and Parkfield three-dimensional crustal velocity models computed by Michelini (1991) is integrated with information on slip behavior provided by the distributions of earthquakes located using, the three-dimensional models and by surface creep data to study the relationships between large-scale lithological heterogeneity and slip segmentation along these two sections of the fault zone.

  5. Significance of recurrent fault movement at Grays Point quarry, southeast Missouri

    SciTech Connect (OSTI)

    Diehl, S.F.; Throckmorton, C.K. ); Clendenin, C.W. )

    1993-03-01

    Geologic relationships indicate recurrent movement on a fault exposed at Grays Point, MO. Faulting offsets Middle-Late Ordovician Plattin Group, Decorah Group, Kimmswick Limestone, and Maquoketa Group strata. In plan, the fault is characterized by a relatively narrow zone (30--70 m) of northeast-striking fault slices associated with a northwest-striking zone of right-stepping en echelon fractures. This systematic fracture-fault array identifies right-lateral strike-slip movement. A vertically offset basal Decorah Group contact shows 22 m of down-to-the-southeast dip slip, which indicates a component of oblique slip. Oldest recognizable movement on the fault is evidenced by Maquoketa Group strata that fill a northeast-striking, wedge-shaped synform. Post-Ordovician movement along an adjacent subvertical fault displaces part of this synform 300 m right laterally. In thin section, the northwest-striking fracture set shows a polyphase history of deformation indicated by cataclastic textures and intrusion of carbonate-rich fluids. Three periods of movement occurred: (1) initial fracturing sealed by authigenic mineral cements; (2) renewed fracturing associated with recrystallization of sub-rounded clasts; and (3) subsequent brecciation marked by angular clasts and filling of fractures and vugs. Each successive fluid intrusion is characterized by an increase in grain size of the authigenic cement. The fault is subparallel to the regional, northeast-striking English Hill fault system. Polyphase oblique-slip deformation suggests that the fault, like others in southeastern Missouri, is a reactivated Late Proterozoic-Cambrian zone of weakness. Initial fault reactivation occurred during Middle-Late Ordovician as opposed to Devonian, as commonly interpreted for southeast Missouri. Multiple authigenic mineral cements imply that fluids may have been an important factor influencing the fault's tendency to be reactivated.

  6. Development of Characterization Technology for Fault Zone Hydrology

    SciTech Connect (OSTI)

    Karasaki, Kenzi; Onishi, Tiemi; Gasperikova, Erika; Goto, Junichi; Tsuchi, Hiroyuki; Miwa, Tadashi; Ueta, Keiichi; Kiho, Kenzo; MIyakawa, Kimio

    2010-08-06

    Several deep trenches were cut, and a number of geophysical surveys were conducted across the Wildcat Fault in the hills east of Berkeley, California. The Wildcat Fault is believed to be a strike-slip fault and a member of the Hayward Fault System, with over 10 km of displacement. So far, three boreholes of ~;; 150m deep have been core-drilled and borehole geophysical logs were conducted. The rocks are extensively sheared and fractured; gouges were observed at several depths and a thick cataclasitic zone was also observed. While confirming some earlier, published conclusions from shallow observations about Wildcat, some unexpected findings were encountered. Preliminary analysis indicates that Wildcat near the field site consists of multiple faults. The hydraulic test data suggest the dual properties of the hydrologic structure of the fault zone. A fourth borehole is planned to penetrate the main fault believed to lie in-between the holes. The main philosophy behind our approach for the hydrologic characterization of such a complex fractured system is to let the system take its own average and monitor a long term behavior instead of collecting a multitude of data at small length and time scales, or at a discrete fracture scale and to ?up-scale,? which is extremely tenuous.

  7. Reservoir-scale fracture permeability in the Dixie Valley, Nevada, geothermal field

    SciTech Connect (OSTI)

    Barton, C.A.; Zoback, M.D.; Hickman, S.; Morin, R.; Benoit, D.

    1998-08-01

    Wellbore image data recorded in six wells penetrating a geothermal reservoir associated with an active normal fault at Dixie Valley, Nevada, were used in conjunction with hydrologic tests and in situ stress measurements to investigate the relationship between reservoir productivity and the contemporary in situ stress field. The analysis of data from wells drilled into productive and non-productive segments of the Stillwater fault zone indicates that fractures must be both optimally oriented and critically stressed to have high measured permeabilities. Fracture permeability in all wells is dominated by a relatively small number of fractures oriented parallel to the local trend of the Stillwater Fault. Fracture geometry may also play a significant role in reservoir productivity. The well-developed populations of low angle fractures present in wells drilled into the producing segment of the fault are not present in the zone where production is not commercially viable.

  8. High-definition analysis of fluid-induced seismicity related to the mesoscale hydromechanical properties of a fault zone

    E-Print Network [OSTI]

    Vallée, Martin

    -strain and seismic measurements taken in the fractured damage zone during the pressurization indicated that seismicity is triggered along low-permeable, highly rigid, low-dip angle, mesoscale-inherited fractures where-so-rigid, aseismic, sub- vertical, fault-related fractures. Using a three-dimensional distinct-element representation

  9. Modeling fault-zone guided waves of microearthquakes in a geothermal...

    Open Energy Info (EERE)

    the identification and modeling of such guided waves is an effective tool to locate fracture-induced, low-velocity fault-zone structures in geothermal fields. Authors Lou, M.;...

  10. Lithological influence of aggregate in the alkali-carbonate reaction

    SciTech Connect (OSTI)

    Lopez-Buendia, A.M. . E-mail: angel.lopez@aidico.es; Climent, V. . E-mail: vcliment@grupogla.com; Verdu, P.

    2006-08-15

    The reactivity of carbonate rock with the alkali content of cement, commonly called alkali-carbonate reaction (ACR), has been investigated. Alkali-silica reaction (ASR) can also contribute in the alkali-aggregate reaction (AAR) in carbonate rock, mainly due to micro- and crypto-crystalline quartz or clay content in carbonate aggregate. Both ACR and ASR can occur in the same system, as has been also evidenced on this paper. Carbonate aggregate samples were selected using lithological reactivity criteria, taking into account the presence of dedolomitization, partial dolomitization, micro- and crypto-crystalline quartz. Selected rocks include calcitic dolostone with chert (CDX), calcitic dolostone with dedolomitization (CDD), limestone with chert (LX), marly calcitic dolostone with partial dolomitization (CD), high-porosity ferric dolostone with clays (FD). To evaluate the reactivity, aggregates were studied using expansion tests following RILEM AAR-2, AAR-5, a modification using LiOH AAR-5Li was also tested. A complementary study was done using petrographic monitoring with polarised light microscopy on aggregates immersed in NaOH and LiOH solutions after different ages. SEM-EDAX has been used to identify the presence of brucite as a product of dedolomitization. An ACR reaction showed shrinkage of the mortar bars in alkaline solutions explained by induced dedolomitization, while an ASR process typically displayed expansion. Neither shrinkage nor expansion was observed when mortar bars were immersed in solutions of lithium hydroxide. Carbonate aggregate classification with AAR pathology risk has been elaborated based on mechanical behaviours by expansion and shrinkage. It is proposed to be used as a petrographic method for AAR diagnosis to complement the RILEM AAR1 specifically for carbonate aggregate. Aggregate materials can be classified as I (non-reactive), II (potentially reactive), and III (probably reactive), considering induced dedolomitization ACR (dedolomitization degree) and ASR.

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

    SciTech Connect (OSTI)

    Gao, Dengliang

    2013-03-01

    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.

  12. Flemish fieldstone: unravelling lithological differences and diagenesis Research Unit: Sedimentary Geology and Engineering Geology

    E-Print Network [OSTI]

    Gent, Universiteit

    Flemish fieldstone: unravelling lithological differences and diagenesis Research Unit: Sedimentary Geology and Engineering Geology Topic: Fieldstone, natural stone, diagenesis, microscopy with a great interest in sedimentation processes and diagenesis, in petrology and Flemish stratigraphy

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

    E-Print Network [OSTI]

    Xue, Wenxu

    2011-02-22

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

  14. Limitations for detecting small-scale faults using the coherency analysis of seismic data 

    E-Print Network [OSTI]

    Barnett, David Benjamin

    2006-08-16

    be distinguished from noise. Results from application of the coherency analysis were applied to the characterization of a very deep fault and fracture system imaged by a field seismic data set. A series of reverse and strike-slip faults were detected and mapped...

  15. Evolution of vertical faults at an extensional plate boundary, southwest Iceland

    E-Print Network [OSTI]

    Kattenhorn, Simon

    Evolution of vertical faults at an extensional plate boundary, southwest Iceland James V. Grant1 Abstract Vertical faults having both opening and vertical displacements are common in southwest Iceland of both oblique and normal spreading in southwest Iceland. Individual fracture segments are commonly

  16. Recurrent faulting and petroleum accumulation, Cat Creek Anticline, central Montana

    SciTech Connect (OSTI)

    Nelson, W.J. (Illinois State Geological Survey, Champaign (United States))

    1991-06-01

    The Cat Creek anticline, scene of central Montana's first significant oil discovery, is underlain by a south-dipping high-angle fault (Cat Creek fault) that has undergone several episodes of movement with opposite sense of displacement. Borehole data suggest that the Cat Creek fault originated as a normal fault during Proterozoic rifting concurrent with deposition of the Belt Supergroup. Reverse faulting took place in Late Cambrian time, and again near the end of the Devonian Period. The Devonian episode, coeval with the Antler orogeny, raised the southern block several hundred feet. The southern block remained high through Meramecian time, then began to subside. Post-Atokan, pre-Middle Jurassic normal faulting lowered the southern block as much as 1,500 ft. During the Laramide orogeny (latest Cretaceous-Eocene) the Cat Creek fault underwent as much as 4,000 ft of reverse displacement and a comparable amount of left-lateral displacement. The Cat Creek anticline is a fault-propagation fold; en echelon domes and listric normal faults developed along its crest in response to wrenching. Oil was generated mainly in organic-rich shales of the Heath Formation (upper Chesterian Series) and migrated upward along tectonic fractures into Pennsylvanian, Jurassic, and Cretaceous reservoir rocks in structural traps in en echelon domes. Production has been achieved only from those domes where structural closure was retained from Jurassic through Holocene time.

  17. Mechanical properties and modeling of seal-forming lithologies

    SciTech Connect (OSTI)

    Kronenberg, A.K.; Russell, J.E.; Carter, N.L.; Mazariegos, R.; Ibanez, W.

    1993-01-01

    Specific goals and accomplishments of this research include: (1) The evaluation of models of salt diaper ascent that involve either power law, dislocation creep as determined experimentally by Horseman et al. (1993) or linear, fluid-assisted creep as reported by Spiers et al. (1988, 1990, 1992). We have compared models assuming these two, experimentally evaluated flow laws and examined the predictions they make regarding diaper incubation periods, ascent velocities, deviatoric stresses and strain rates. (2) The evaluation of the effects of differential loading on the initiation an of salt structures. (3) Examination of the role of basement faults on the initiation and morphologic evolution of salt structures. (4) Evaluation of the mechanical properties of shale as a function of pressure and determination of the nature of its brittle-ductile transition. (5) Evaluation of the mechanical anisotropies of shales with varying concentrations, distributions and preferred orientations of clay. (6) The determination of temperature and ratedependencies of strength for a shale constitutive model that can be used in numerical models that depend on viscous formulations. (7) Determination of the mechanisms of deformation for argillaceous rocks over awide range of conditions. (8) Evaluation of the effects of H[sub 2]O within clay interlayers, as adsorbed surface layers.

  18. Area balance and strain in an extensional fault system: Strategies for improved oil recovery in fractured chalk, Gilbertown Field, southwestern Alabama -- Year 2. Annual report, March 1997--March 1998

    SciTech Connect (OSTI)

    Pashin, J.C.; Raymond, D.E.; Rindsberg, A.K.; Alabi, G.G.; Carroll, R.E.

    1998-09-01

    Gilbertown Field is the oldest oil field in Alabama and has produced oil from fractured chalk of the Cretaceous Selma Group and glauconitic sandstone of the Eutaw Formation. Nearly all of Gilbertown Field is still in primary recovery, although waterflooding has been attempted locally. The objective of this project is to analyze the geologic structure and burial history of Mesozoic and Tertiary strata in Gilbertown Field and adjacent areas in order to suggest ways in which oil recovery can be improved. Indeed, the decline of oil production to marginally economic levels in recent years has made this type of analysis timely and practical. Key technical advancements being sought include understanding the relationship of requisite strain to production in Gilbertown reservoirs, incorporation of synsedimentary growth factors into models of area balance, quantification of the relationship between requisite strain and bed curvature, determination of the timing of hydrocarbon generation, and identification of the avenues and mechanisms of fluid transport.

  19. Optimal fault location 

    E-Print Network [OSTI]

    Knezev, Maja

    2008-10-10

    sequence of events newly obtained recording belongs. Software prototype of the proposed automated fault location analysis is developed using Java programming language. Fault location analysis is automatically triggered by appearance of new event files in a...

  20. Fracture Properties From Seismic Scattering

    E-Print Network [OSTI]

    Burns, Daniel R.

    2007-01-01

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

  1. Discrete Fracture Reservoir Simulation

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

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

  2. Potential Contaminant Pathways from Hydraulically Fractured Shale to Aquifers

    E-Print Network [OSTI]

    that fracking the shale could reduce that transport time to tens or hundreds of years. Conductive faults to reach a new equilibrium reflecting the significant changes caused by fracking the shale, which could for development. Hydraulic fracturing (fracking, the industry term for the operation; Kramer 2011) loosens

  3. Fault simulation and test generation for small delay faults 

    E-Print Network [OSTI]

    Qiu, Wangqi

    2007-04-25

    Delay faults are an increasingly important test challenge. Traditional delay fault models are incomplete in that they model only a subset of delay defect behaviors. To solve this problem, a more realistic delay fault model has been developed which...

  4. AVA simultaneous inversion of partially stacked seismic amplitude data for the spatial delineation of lithology and fluid units of deepwater

    E-Print Network [OSTI]

    Torres-Verdín, Carlos

    of lithology and fluid units of deepwater hydrocarbon reservoirs in the central Gulf of Mexico Arturo Contreras and delineate deepwater hydrocarbon reservoirs in the central Gulf of Mexico. Detailed AVA fluid/ lithology to fluid substitution. AVA reflectivity and angle-gather modeling indicate that the shale/sand interfaces

  5. Advanced Characterization of Fractured Reservoirs in Carbonate Rocks: The Michigan Basin

    SciTech Connect (OSTI)

    Wood, James R.; Harrison, William B.

    2002-12-02

    The purpose of the study was to collect and analyze existing data on the Michigan Basin for fracture patterns on scales ranging form thin section to basin. The data acquisition phase has been successfully concluded with the compilation of several large digital databases containing nearly all the existing information on formation tops, lithology and hydrocarbon production over the entire Michigan Basin. These databases represent the cumulative result of over 80 years of drilling and exploration.

  6. Solar system fault detection

    DOE Patents [OSTI]

    Farrington, R.B.; Pruett, J.C. Jr.

    1984-05-14

    A fault detecting apparatus and method are provided for use with an active solar system. The apparatus provides an indication as to whether one or more predetermined faults have occurred in the solar system. The apparatus includes a plurality of sensors, each sensor being used in determining whether a predetermined condition is present. The outputs of the sensors are combined in a pre-established manner in accordance with the kind of predetermined faults to be detected. Indicators communicate with the outputs generated by combining the sensor outputs to give the user of the solar system and the apparatus an indication as to whether a predetermined fault has occurred. Upon detection and indication of any predetermined fault, the user can take appropriate corrective action so that the overall reliability and efficiency of the active solar system are increased.

  7. Solar system fault detection

    DOE Patents [OSTI]

    Farrington, Robert B. (Wheatridge, CO); Pruett, Jr., James C. (Lakewood, CO)

    1986-01-01

    A fault detecting apparatus and method are provided for use with an active solar system. The apparatus provides an indication as to whether one or more predetermined faults have occurred in the solar system. The apparatus includes a plurality of sensors, each sensor being used in determining whether a predetermined condition is present. The outputs of the sensors are combined in a pre-established manner in accordance with the kind of predetermined faults to be detected. Indicators communicate with the outputs generated by combining the sensor outputs to give the user of the solar system and the apparatus an indication as to whether a predetermined fault has occurred. Upon detection and indication of any predetermined fault, the user can take appropriate corrective action so that the overall reliability and efficiency of the active solar system are increased.

  8. Development of Hydrologic Characterization Technology of Fault Zones

    SciTech Connect (OSTI)

    Karasaki, Kenzi; Onishi, Tiemi; Wu, Yu-Shu

    2008-03-31

    Through an extensive literature survey we find that there is very limited amount of work on fault zone hydrology, particularly in the field using borehole testing. The common elements of a fault include a core, and damage zones. The core usually acts as a barrier to the flow across it, whereas the damage zone controls the flow either parallel to the strike or dip of a fault. In most of cases the damage zone isthe one that is controlling the flow in the fault zone and the surroundings. The permeability of damage zone is in the range of two to three orders of magnitude higher than the protolith. The fault core can have permeability up to seven orders of magnitude lower than the damage zone. The fault types (normal, reverse, and strike-slip) by themselves do not appear to be a clear classifier of the hydrology of fault zones. However, there still remains a possibility that other additional geologic attributes and scaling relationships can be used to predict or bracket the range of hydrologic behavior of fault zones. AMT (Audio frequency Magneto Telluric) and seismic reflection techniques are often used to locate faults. Geochemical signatures and temperature distributions are often used to identify flow domains and/or directions. ALSM (Airborne Laser Swath Mapping) or LIDAR (Light Detection and Ranging) method may prove to be a powerful tool for identifying lineaments in place of the traditional photogrammetry. Nonetheless not much work has been done to characterize the hydrologic properties of faults by directly testing them using pump tests. There are some uncertainties involved in analyzing pressure transients of pump tests: both low permeability and high permeability faults exhibit similar pressure responses. A physically based conceptual and numerical model is presented for simulating fluid and heat flow and solute transport through fractured fault zones using a multiple-continuum medium approach. Data from the Horonobe URL site are analyzed to demonstrate the proposed approach and to examine the flow direction and magnitude on both sides of a suspected fault. We describe a strategy for effective characterization of fault zone hydrology. We recommend conducting a long term pump test followed by a long term buildup test. We do not recommend isolating the borehole into too many intervals. We do recommend ensuring durability and redundancy for long term monitoring.

  9. Dual-porosity reservoir modeling of the fractured Hanifa reservoir, Abqaiq Field, Saudi Arabia

    SciTech Connect (OSTI)

    Luthy, S.T. [Saudi Aramco, Dhahran (Saudi Arabia)

    1995-08-01

    Fractures play a significant role in the transmissibility of the Hanifa reservoir at Abqaiq Field. The Hanifa is a Type 2 fractured reservoir characterized by a finely-crystalline carbonate matrix which contains most of the reservoir storage porosity, and a stylolitic fracture system which provides essential permeability. Integration of borehole imaging data with available open-hole log, core, and well-test data from horizontal and vertical wells allowed for the distribution of fracture parameters, including fracture density, aperture, porosity, and permeability throughout a geocellular model. Analysis of over 5000 fractures showed that changes in lithology, grain size, and/or bed thickness do not correlate with changes in fracture densities. Review of P- and S-wave log data showed that porosity is negatively correlated with fracture density and mechanical rock strength. From these relationships, it was possible to utilize additional wells where porosity log data was available to calculate fracture densities. These wells were used to generate matrix porosity and permeability as well as fracture density attributes in a 12-sequence, 29-layer geocellular model. Fracture permeabilities compare favorably with well-test derived productivity indices. Three-dimensional visualization of model attributes showed that a monotonous and low (<10 md) distribution of matrix- related permeability contrasts sharply with highly variable and relatively high (ER 50 md) permeabilities of the fracture system. Reliability of the geocellular model to predict fracture densities and associated permeabilities has been confirmed by subsequent drilling of high cost horizontal wells, and is being used in reservoir engineering and development drilling planning efforts.

  10. Transient fault modeling and fault injection simulation 

    E-Print Network [OSTI]

    Yuan, Xuejun

    1996-01-01

    An accurate transient fault model is presented in this thesis. A 7-term exponential current upset model is derived from the results of a device-level, 3-dimensional, single-event-upset simulation. A curve-fitting algorithm is used to extract...

  11. Effect of faulting on ground-water movement in the Death Valley region, Nevada and California

    SciTech Connect (OSTI)

    Faunt, C.C.

    1997-12-31

    This study characterizes the hydrogeologic system of the Death Valley region, an area covering approximately 100,000 square kilometers. The study also characterizes the effects of faults on ground-water movement in the Death Valley region by synthesizing crustal stress, fracture mechanics,a nd structural geologic data. The geologic conditions are typical of the Basin and Range Province; a variety of sedimentary and igneous intrusive and extrusive rocks have been subjected to both compressional and extensional deformation. Faulting and associated fracturing is pervasive and greatly affects ground-water flow patterns. Faults may become preferred conduits or barriers to flow depending on whether they are in relative tension, compression, or shear and other factors such as the degree of dislocations of geologic units caused by faulting, the rock types involved, the fault zone materials, and the depth below the surface. The current crustal stress field was combined with fault orientations to predict potential effects of faults on the regional ground-water flow regime. Numerous examples of fault-controlled ground-water flow exist within the study area. Hydrologic data provided an independent method for checking some of the assumptions concerning preferential flow paths. 97 refs., 20 figs., 5 tabs.

  12. Geomechanics of hydraulic fracturing microseismicity

    E-Print Network [OSTI]

    Ze'ev, Reches

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

  13. Geomechanical properties of tight, low-porosity reser-voirs are largely governed by natural fracture networks.

    E-Print Network [OSTI]

    Tsvankin, Ilya

    inversion methods that operate with both 3D wide- azimuth surface data and VSP (vertical seismic profiling of surface seismic data. However, the corre- lation between areas of high fracture density and fault locations is not always straightforward. Therefore, fracture characterization increasingly relies on seismic

  14. Fracture Permeability and in Situ Stress in the Dixie Valley, Nevada, Geothermal Reservoir

    SciTech Connect (OSTI)

    M. D. Zoback

    1999-03-08

    We have collected and analyzed fracture and fluid flow data from wells both within and outside the producing geothermal reservoir at Dixie Valley. Data from wellbore imaging and flow tests in wells outside the producing field that are not sufficiently hydraulically connected to the reservoir to be of commercial value provide both the necessary control group of fracture populations and an opportunity to test the concepts proposed in this study on a regional, whole-reservoir scale. Results of our analysis indicate that fracture zones with high measured permeabilities within the producing segment of the fault are parallel to the local trend of the Stillwater fault and are optimally oriented and critically stressed for frictional failure in the overall east-southeast extensional stress regime measured at the site. In contrast, in the non-producing (i.e., relatively impermeable:) well 66-21 the higher ratio of S{sub hmin} to S{sub v} acts to decrease the shear stress available to drive fault slip. Thus, although many of the fractures at this site (like the Stillwater fault itself) are optimally oriented for normal faulting they are not critically stressed for frictional failure. Although some of the fractures observed in the non-producing well 45-14 are critically stressed for frictional failure, the Stillwater fault zone itself is frictionally stable. Thus, the high horizontal differential stress (i.e., S{sub Hmax}-S{sub hmin}) together with the severe misorientation of the Stillwater fault zone for normal faulting at this location appear to dominate the overall potential for fluid flow.

  15. High velocity impact fracture

    E-Print Network [OSTI]

    Teng, Xiaoqing

    2005-01-01

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

  16. Fracture Characteristics in a Disposal Pit on Mesita del Buey, Los Alamos National Laboratory

    SciTech Connect (OSTI)

    David T. Vaniman; Steven L. Reneau

    1998-12-01

    The characteristics of fractures in unit 2 of the Tshirege Member of the Bandelier Tuff were documented in Pit 39, a newly excavated 13.7 m deep disposal pit at Material Disposal Area G on Mesita del Buey. The average spacing between fractures is about 1.0 to 1.3 m, the average fracture aperture is about 3 to 5 mm, and the average fracture dip is about 76o to 77o. Fracture spacing and dip in Pit 39 are generally consistent with that reported from other fracture studies on the Pajarito Plateau, although the fracture apertures in Pit 39 are less than reported elsewhere. Measured fracture orientations are strongly affected by biases imparted by the orientations of the pit walls, which, combined with a small data set, make identification of potential preferred orientations dlfflcult. The most prominent fracture orientations observed in Pit 39, about E-W and N20E, are often not well represented elsewhere on the Pajarito Plateau. Fracture fills contain smectite to about 3 m depth, and calcite and opal may occur at all depths, principally associated with roots or root fossils (rhizoliths). Roots of pifion pine extend in fractures to the bottom of the pit along the north side, perhaps indicating a zone of preferred infiltration of water. Finely powdered tuff with clay-sized particles occurs within a number of fractures and may record abrasive disaggregation associated with small amounts of displacement on minor local faults.

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

    E-Print Network [OSTI]

    Forbis, Robert E.

    2014-01-01

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

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

    E-Print Network [OSTI]

    Forbis, Robert E.

    2014-01-01

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

  19. Characterization of EGS Fracture Network Lifecycles

    SciTech Connect (OSTI)

    Gillian R. Foulger

    2008-03-31

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

  20. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, Jeffrey R.; Glaser, Steven D.

    2008-01-01

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

  1. Catalog of borehole lithologic logs from the 600 Area, Hanford Site

    SciTech Connect (OSTI)

    Fecht, K R; Lillie, J T

    1982-03-01

    Rockwell Hanford Operations (Rockwell) geoscientists are studying the Hanford Site subsurface environment to assure safe management operations, disposal, and storage of radioactive waste. As part of this effort, geoscientists have collected geotechnical data from about 3000 boreholes drilled on the Hanford Site since the early 1900s. These boreholes have been used for subsurface geologic, hydrologic, and engineering investigation, water supply, ground-water monitoring, and natural gas production. This report is a catalog of all obtainable (about 800) lithologic logs from boreholes in a portion of the Hanford Site known as the 600 Area.

  2. Core Lithology, Valles Caldera No. 1, New Mexico | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTIONRobertsdale, Alabama (Utility Company)| Open(Evans,Oregon:Volcano, Hawaii | Open EnergyLithology,

  3. The detection of high impedance faults using random fault behavior 

    E-Print Network [OSTI]

    Carswell, Patrick Wayne

    1988-01-01

    and cleared by conventional overcurrent devices. Examples of high impedance fault scenarios include broken conductors and grounded conductors as is the case with tree faults. Most high impedance fault situations occur on the power distribution system due... of the most promising proposals are presented and commented upon as to their weaknesses and limitations if implemented on an actual power distribution system. A new algorithm is developed which attempts to detect the presence of a high impedance fault...

  4. Fault tolerant linear actuator

    DOE Patents [OSTI]

    Tesar, Delbert

    2004-09-14

    In varying embodiments, the fault tolerant linear actuator of the present invention is a new and improved linear actuator with fault tolerance and positional control that may incorporate velocity summing, force summing, or a combination of the two. In one embodiment, the invention offers a velocity summing arrangement with a differential gear between two prime movers driving a cage, which then drives a linear spindle screw transmission. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module.

  5. Computer hardware fault administration

    DOE Patents [OSTI]

    Archer, Charles J. (Rochester, MN); Megerian, Mark G. (Rochester, MN); Ratterman, Joseph D. (Rochester, MN); Smith, Brian E. (Rochester, MN)

    2010-09-14

    Computer hardware fault administration carried out in a parallel computer, where the parallel computer includes a plurality of compute nodes. The compute nodes are coupled for data communications by at least two independent data communications networks, where each data communications network includes data communications links connected to the compute nodes. Typical embodiments carry out hardware fault administration by identifying a location of a defective link in the first data communications network of the parallel computer and routing communications data around the defective link through the second data communications network of the parallel computer.

  6. Predicting fault damage zones by modeling dynamic rupture propagation and comparison

    E-Print Network [OSTI]

    Dunham, Eric M.

    seismic reflection data, image logs in wellbores, and studies of exhumed core. Of course, 3-D seismic data accurately. Direct observations of fractures and faults at depth in reservoirs typically come from 3-D are approximately 60­100 m wide. These attributes are similar to those observed in the SSC reservoir using wellbore

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

    E-Print Network [OSTI]

    Sesetty, Varahanaresh

    2012-10-19

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

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

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    2012-01-01

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

  9. Geothermal Ultrasonic Fracture Imager

    Broader source: Energy.gov [DOE]

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

  10. Geomechanics of hydraulic fracturing microseismicity

    E-Print Network [OSTI]

    Ze'ev, Reches

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

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

    E-Print Network [OSTI]

    Lolon, Elyezer P.

    2006-04-12

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

  12. Tectonic controls on fracture permeability in a geothermal reservoir at Dixie Valley, Nevada

    SciTech Connect (OSTI)

    Hickman, S.; Zoback, M.

    1998-08-01

    To help determine the nature and origins of permeability variations within a fault-hosted geothermal reservoir at Dixie Valley, Nevada, the authors conducted borehole televiewer logging and hydraulic fracturing stress measurements in six wells drilled into the Stillwater fault zone at depths of 2--3 km. Televiewer logs from wells penetrating the highly permeable portion of the fault zone revealed extensive drilling-induced tensile fractures. As the Stillwater fault at this location dips S45{degree}E at {approximately} 53{degree} it is nearly at the optimal orientation for normal faulting in the current stress field. Hydraulic fracturing tests from these permeable wells show that the magnitude of S{sub hmin} is very low relative to the vertical stress S{sub v}. Similar measurements conducted in two wells penetrating a relatively impermeable segment of the Stillwater fault zone 8 and 20 km southwest of the producing geothermal reservoir indicate that the orientation of S{sub hmin} is S20{degree}E and S41{degree}E, respectively, with S{sub hmin}/S{sub v} ranging from 0.55--0.64 at depths of 1.9--2.2 km. This stress orientation is near optimal for normal faulting on the Stillwater fault in the northernmost non-producing well, but {approximately} 40{degree} rotated from the optimal orientation for normal faulting in the southernmost well. The observation that borehole breakouts were present in these nonproducing wells, but absent in wells drilled into the permeable main reservoir, indicates a significant increase in the magnitude of maximum horizontal principal stress, S{sub Hmax}, in going from the producing to non-producing segments of the fault. The increase in S{sub Hmaz}, coupled with elevated S{sub hmin}/S{sub v} values and a misorientation of the Stillwater fault zone with respect to the principal stress directions, leads to a decrease in the proximity of the fault zone to Coulomb failure. This suggests that a necessary condition for high reservoir permeability is that the Stillwater fault zone be critically stressed for frictional failure in the current stress field.

  13. Fracture mechanics: 26. volume

    SciTech Connect (OSTI)

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

    1995-12-31

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

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

    SciTech Connect (OSTI)

    Robert Jacobi; John Fountain

    2001-06-30

    In the structure task, the authors completed reducing the data they had collected from a N-S transect on the east side of Seneca Lake. They 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 definitely 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 some exposures along Seneca Lake, but the lensing nature of the individual sandstones can preclude long-distance definite 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 they display an interpreted seismic line that crosses the Glodes Corners and Muck Farms 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 them to extrapolate Trenton-Black River trends away from confirmatory seismic lines.

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

    SciTech Connect (OSTI)

    Robert Jacobi; John Fountain

    2002-01-30

    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.

  16. Fault interaction near Hollister, California

    SciTech Connect (OSTI)

    Mavko, G.M.

    1982-09-10

    A numerical model is used to study fault stress slip near Hollister, California. The geometrically complex system of interacting faults, including the San Andreas, Calaveras, Sargent, and Busch faults, is approximated with a two-dimensional distribution of short planar fault segments in an elastic medium. The steady stress and slip rate are simulated by specifying frictional strength and stepping the remote stress ahead in time. The resulting computed fault stress is roughly proportional to the observed spatial density of small earthquakes, suggesting that the distinction between segments characterized by earthquakes and those with aseismic creep results, in part, from geometry. A nonsteady simulation is made by introducing, in addition, stress drops for individual moderate earthquakes. A close fit of observed creep with calculated slip on the Calaveras and San Andreas faults suggests that many changes in creep rate (averaged over several months) are caused by local moderate earthquakes. In particular, a 3-year creep lag preceding the August 6, 1979, Coyote Lake earthquake on the Calaveras fault seems to have been a direct result of the November 28, 1974, Thanksgiving Day earthquake on the Busch fault. Computed lags in slip rate preceding some other moderate earthquakes in the area are also due to earlier earthquakes. Although the response of the upper 1 km of the fault zone may cause some individual creep events and introduce delays in others, the long-term rate appears to reflect deep slip.

  17. Fault current limiter

    DOE Patents [OSTI]

    Darmann, Francis Anthony

    2013-10-08

    A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.

  18. Fault Current Limiters

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12, 2015Executive Order14, 20111,FYDepartment of5 NovemberFarms to FuelFault

  19. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, J R; Glaser, Steven D

    2007-01-01

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

  20. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, Jeffrey R.; Glaser, Steven D.

    2008-01-01

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

  1. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, J R; Glaser, Steven D

    2007-01-01

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

  2. Colorado Regional Faults

    SciTech Connect (OSTI)

    Hussein, Khalid

    2012-02-01

    Citation Information: Originator: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Originator: Colorado Geological Survey (CGS) Publication Date: 2012 Title: Regional Faults Edition: First Publication Information: Publication Place: Earth Science & Observation Center, Cooperative Institute for Research in Environmental Science, University of Colorado, Boulder Publisher: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Description: This layer contains the regional faults of Colorado Spatial Domain: Extent: Top: 4543192.100000 m Left: 144385.020000 m Right: 754585.020000 m Bottom: 4094592.100000 m Contact Information: Contact Organization: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Contact Person: Khalid Hussein Address: CIRES, Ekeley Building Earth Science & Observation Center (ESOC) 216 UCB City: Boulder State: CO Postal Code: 80309-0216 Country: USA Contact Telephone: 303-492-6782 Spatial Reference Information: Coordinate System: Universal Transverse Mercator (UTM) WGS’1984 Zone 13N False Easting: 500000.00000000 False Northing: 0.00000000 Central Meridian: -105.00000000 Scale Factor: 0.99960000 Latitude of Origin: 0.00000000 Linear Unit: Meter Datum: World Geodetic System 1984 (WGS ’984) Prime Meridian: Greenwich Angular Unit: Degree Digital Form: Format Name: Shape file

  3. Optimized Fault Location Final Project Report

    E-Print Network [OSTI]

    Optimized Fault Location Final Project Report Power Systems Engineering Research Center A National Engineering Research Center Optimized Fault Location Concurrent Technologies Corporation Final Project Report

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

    E-Print Network [OSTI]

    Underwood, Jarrod

    2013-11-15

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

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

    E-Print Network [OSTI]

    Ahmed, Ibraheem 1987-

    2012-11-30

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

  6. Observer-based fault detection for nuclear reactors

    E-Print Network [OSTI]

    Li, Qing, 1972-

    2001-01-01

    This is a study of fault detection for nuclear reactor systems. Basic concepts are derived from fundamental theories on system observers. Different types of fault- actuator fault, sensor fault, and system dynamics fault ...

  7. Thrust faulting in Temblor Range, Kern County, California

    SciTech Connect (OSTI)

    Simonson, R.R.

    1991-02-01

    Surface and subsurface studies confirm the presence of overthrusting in the Temblor Range between Gonyer Canyon and Recruit Pass. In the subsurface, three wells have penetrated the Cree fault, the Hudbay Cree' No. 1 (7,300 ft), the Frantzen Oil Company Cree' No. 1 (5,865 ft) and the Arco Cree Fee' 1A well (5,915 ft). Below the fault, 25 to 35{degree} of westerly dips on the west flank of the sub-thrust Phelps anticline are encountered. The McDonald section below the fault is comprised of siliceous fractured shale which contains live oil and gas showings. A drill-stem test of the interval from 8,247 to 8,510 ft in the Frantzen well resulted in a recovery of 1,200 ft clean 34{degree} oil and 40 MCF per day gas. The shut in pressure was 3,430 lb, which is a normal hydrostatic pressure common to the producing structures in the southern San Joaquin Valley. The equivalent of this interval has produced over 7,000 bbl of oil in the Arco Cree' 1A well. The Arco Cree Fee' No. 1A well crossed the axis of the Phelps Anticline as indicated by good dipmeter and bottomed in Lower Zemorrian at 14,512 ft total depth. This well was not drilled deep enough to reach the Point of Rocks Sand and did not test the gas showings in the lower Miocene section. In the Gonyer Canyon area, subsurface evidence indicated conditions are similar to those in the Cree area because a large structure is present below a thrust fault. It is believed that significant accumulations will be found beneath thrust faults in the eastern part of the Temblor Range where conditions are similar to those that were instrumental in forming fields such as the Elk Hills, B. V. Hills, Belgian Anticline and others.

  8. Fracture Conductivity of the Eagle Ford Shale 

    E-Print Network [OSTI]

    Guzek, James J

    2014-07-25

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

  9. Reservoir fracture characterizations from seismic scattered waves

    E-Print Network [OSTI]

    Fang, Xinding

    2012-01-01

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

  10. Merguerian, Charles, 1995a, The Taconic problem -alive and well in New York City The Taconic problem in NYC, focuses on ductile-fault imbrication of three lithologically

    E-Print Network [OSTI]

    Merguerian, Charles

    Merguerian, Charles, 1995a, The Taconic problem - alive and well in New York City (NYC, 1995a, The Taconic problem - alive and well in New York City (NYC) (abs.): Geological Society

  11. Microearthquake Technology for EGS Fracture Characterization...

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

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

  12. Fracture prediction in metal sheets

    E-Print Network [OSTI]

    Lee, Young-Woong

    2005-01-01

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

  13. Fluid Flow Modeling in Fractures

    E-Print Network [OSTI]

    Sarkar, Sudipta

    2004-01-01

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

  14. Arc fault detection system

    DOE Patents [OSTI]

    Jha, Kamal N. (Bethel Park, PA)

    1999-01-01

    An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard.

  15. Arc fault detection system

    DOE Patents [OSTI]

    Jha, K.N.

    1999-05-18

    An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard. 1 fig.

  16. Fractured Petroleum Reservoirs

    SciTech Connect (OSTI)

    Firoozabadi, Dr. Abbas

    2000-01-18

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

  17. Fracture Mechanics and Failure Analysis

    E-Print Network [OSTI]

    New South Wales, University of

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

  18. Hot Pot Detail - Evidence of Quaternary Faulting

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

    Lane, Michael

    2013-06-27

    Compilation of published data, field observations and photo interpretation relevant to Quaternary faulting at Hot Pot.

  19. Hot Pot Detail - Evidence of Quaternary Faulting

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

    Lane, Michael

    Compilation of published data, field observations and photo interpretation relevant to Quaternary faulting at Hot Pot.

  20. Infiltration into Fractured Bedrock

    SciTech Connect (OSTI)

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

    2007-09-01

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

  1. Fault-tolerant TCP mechanisms 

    E-Print Network [OSTI]

    Satapati, Suresh Kumar

    2000-01-01

    While fault-tolerance is supported by a variety of critical services that can be accessed over the Internet, they are not robust in that they are oblivious of the impact of their tolerant mechanisms on the service they ...

  2. Q AS A LITHOLOGICAL/HYDROCARBON INDICATOR: FROM FULL WAVEFORM SONIC TO 3D SURFACE SEISMIC

    SciTech Connect (OSTI)

    Jorge O. Parra; C.L. Hackert; L. Wilson; H.A. Collier; J. Todd Thomas

    2006-03-31

    The goal of this project was to develop a method to exploit viscoelastic rock and fluid properties to greatly enhance the sensitivity of surface seismic measurements to the presence of hydrocarbon saturation. To reach the objective, Southwest Research Institute scientists used well log, lithology, production, and 3D seismic data from an oil reservoir located on the Waggoner Ranch in north central Texas. The project was organized in three phases. In the first phase, we applied modeling techniques to investigate seismic- and acoustic-frequency wave attenuation and its effect on observable wave attributes. We also gathered existing data and acquired new data from the Waggoner Ranch field, so that all needed information was in place for the second phase. During the second phase, we developed methods to extract attenuation from borehole acoustic and surface seismic data. These methods were tested on synthetic data constructed from realistic models and real data. In the third and final phase of the project, we applied this technology to a full data set from the Waggoner site. The results presented in this Final Report show that geological conditions at the site did not allow us to obtain interpretable results from the Q processing algorithm for 3D seismic data. However, the Q-log processing algorithm was successfully applied to full waveform sonic data from the Waggoner site. A significant part of this project was technology transfer. We have published several papers and conducted presentations at professional conferences. In particular, we presented the Q-log algorithm and applications at the Society of Exploration Geophysicists (SEG) Development and Production Forum in Austin, Texas, in May 2005. The presentation attracted significant interest from the attendees and, at the request of the SEG delegates, it was placed on the Southwest Research Institute Internet site. The presentation can be obtained from the following link: http://www.swri.org/4org/d15/elecsys/resgeo/ppt/Algorithm.pps In addition, we presented a second application of the Q algorithm at the SEG International Conference in Houston, Texas, in May 2005. The presentation attracted significant interest there as well, and it can be obtained from the following link: http://www.swri.org/4org/d15/elecsys/resgeo/ppt/attenuation.pps.

  3. Internal structure of the Kern Canyon Fault, California: a deeply exhumed strike-slip fault 

    E-Print Network [OSTI]

    Neal, Leslie Ann

    2002-01-01

    Deformation and mineral alteration adjacent to a 2 km long segment of the Kern Canyon fault near Lake Isabella, California are studied to characterize the internal structure of the fault zone and to understand the development of fault structure...

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

    E-Print Network [OSTI]

    Narasimhan, T.N.

    2014-01-01

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

  5. Reservoir fracture mapping using microearthquakes: Austin chalk, Giddings field, TX and 76 field, Clinton Co., KY

    SciTech Connect (OSTI)

    Phillips, W.S.; Rutledge, J.T.; Gardner, T.L.; Fairbanks, T.D.; Miller, M.E.; Schuessler, B.K.

    1996-11-01

    Patterns of microearthquakes detected downhole defined fracture orientation and extent in the Austin chalk, Giddings field, TX and the 76 field, Clinton Co., KY. We collected over 480 and 770 microearthquakes during hydraulic stimulation at two sites in the Austin chalk, and over 3200 during primary production in Clinton Co. Data were of high enough quality that 20%, 31% and 53% of the events could be located, respectively. Reflected waves constrained microearthquakes to the stimulated depths at the base of the Austin chalk. In plan view, microearthquakes defined elongate fracture zones extending from the stimulation wells parallel to the regional fracture trend. However, widths of the stimulated zones differed by a factor of five between the two Austin chalk sites, indicating a large difference in the population of ancillary fractures. Post-stimulation production was much higher from the wider zone. At Clinton Co., microearthquakes defined low-angle, reverse-fault fracture zones above and below a producing zone. Associations with depleted production intervals indicated the mapped fractures had been previously drained. Drilling showed that the fractures currently contain brine. The seismic behavior was consistent with poroelastic models that predicted slight increases in compressive stress above and below the drained volume.

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

    Office of Environmental Management (EM)

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

  7. Sandia Energy - PV Arc-Fault and Ground Fault Detection and Mitigation...

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

    Program Home Stationary Power Energy Conversion Efficiency Solar Energy Photovoltaics PV Systems Reliability PV Arc-Fault and Ground Fault Detection and Mitigation Program PV...

  8. Phase Field Fracture Mechanics.

    SciTech Connect (OSTI)

    Robertson, Brett Anthony

    2015-11-01

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

  9. Procedure for estimating fracture energy from fracture surface roughness

    DOE Patents [OSTI]

    Williford, Ralph E. (Kennewick, WA)

    1989-01-01

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

  10. Brittle Fracture Ductile to Brittle transition

    E-Print Network [OSTI]

    Subramaniam, Anandh

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

  11. FRACTURED PETROLEUM RESERVOIRS

    SciTech Connect (OSTI)

    Abbas Firoozabadi

    1999-06-11

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

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

    SciTech Connect (OSTI)

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

    1995-05-01

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

  13. Fracture permeability in the Matalibong-25 corehole, Tiwi geothermal field, Philippines

    SciTech Connect (OSTI)

    Nielson, D.L.; Moore, J.N.; Clemente, W.C.

    1996-12-31

    The Tiwi geothermal field is located in southern Luzon on the northeast flank of Mt. Malinao, an andesitic volcano that was active 0.5 to 0.06 Ma. Matalibong-25 (Mat-25) was drilled through the Tiwi reservoir to investigate lithologic and fracture controls on reservoir permeability and to monitor reservoir pressure. Continuous core was collected from 2586.5 to 8000 feet (789 to 2439 meters) with greater than 95% recovery. The reservoir rocks observed in Mat-25 consist mainly of andesitic and basaltic lavas and volcaniclastic rocks above 6600 feet depth (2012 meters) and andesitic sediments below, with a transition from subaerial to subaqueous (marine) deposition at 5250 feet (1601 meters). The rocks in the reservoir interval are strongly altered and veined. Common secondary minerals include chlorite, illite, quartz, calcite rite, epidote, anhydrite, adularia and wairakite. An {sup 39}Ar/{sup 40}Ar age obtained on adularia from a quartz-adularia-cemented breccia at a depth of 6066 feet (2012 meters) indicates that the hydrothermal system has been active for at least 320,000 years. Fractures observed in the core were classified as either veins (sealed) or open fractures, with the latter assumed to represent fluid entries in the geothermal system. Since the core was not oriented, only fracture frequency and dip angle with respect to the core axis could be determined. The veins and open fractures are predominantly steeply dipping and have a measured density of up to 0.79 per foot in the vertical well. Below 6500 feet (1982 meters) there is a decrease in fracture intensity and in fluid inclusion temperatures.

  14. Simulation of naturally fractured reservoirs

    SciTech Connect (OSTI)

    Saidi, A.M.

    1983-11-01

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

  15. Fracture-Induced Anisotropic Attenuation

    E-Print Network [OSTI]

    2012-03-23

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

  16. Seismic anisotropy of fractured rock

    E-Print Network [OSTI]

    M. Schoenberg, C. M. Sayers

    2000-02-18

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

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

    SciTech Connect (OSTI)

    Robert Jacobi; John Fountain

    2001-02-28

    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.

  18. Sensor Fault Detection and Isolation System 

    E-Print Network [OSTI]

    Yang, Cheng-Ken

    2014-08-01

    The purpose of this research is to develop a Fault Detection and Isolation (FDI) system which is capable to diagnosis multiple sensor faults in nonlinear cases. In order to lead this study closer to real world applications ...

  19. Characterization of Damage in Sandstones along the Mojave Section of the San Andreas Fault: Implications for the Shallow Extent of Damage

    E-Print Network [OSTI]

    Ben-Zion, Yehuda

    Characterization of Damage in Sandstones along the Mojave Section of the San Andreas Fault: Implications for the Shallow Extent of Damage Generation ORY DOR,1,5 JUDITH S. CHESTER,2 YEHUDA BEN-ZION,1 shallow generation of rock damage during an earthquake rupture, we measure the degree of fracture damage

  20. Boullier The fault zone geology 1 Fault zone geology: lessons from drilling through the Nojima and 1

    E-Print Network [OSTI]

    Boyer, Edmond

    Boullier The fault zone geology 1 Fault zone geology: lessons from active faults with the aim of 11 learning about the geology of the fault all 18 their objectives, have still contributed to a better geological

  1. Interferometric hydrofracture microseism localization using neighboring fracture

    E-Print Network [OSTI]

    Poliannikov, Oleg V.

    2011-05-19

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

  2. 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 ...

  3. On the fracture toughness of advanced materials

    E-Print Network [OSTI]

    Launey, Maximilien E.

    2009-01-01

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

  4. 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. ...

  5. Fault Models for Quantum Mechanical Switching Networks

    E-Print Network [OSTI]

    Jacob Biamonte; Jeff S. Allen; Marek A. Perkowski

    2010-01-19

    The difference between faults and errors is that, unlike faults, errors can be corrected using control codes. In classical test and verification one develops a test set separating a correct circuit from a circuit containing any considered fault. Classical faults are modelled at the logical level by fault models that act on classical states. The stuck fault model, thought of as a lead connected to a power rail or to a ground, is most typically considered. A classical test set complete for the stuck fault model propagates both binary basis states, 0 and 1, through all nodes in a network and is known to detect many physical faults. A classical test set complete for the stuck fault model allows all circuit nodes to be completely tested and verifies the function of many gates. It is natural to ask if one may adapt any of the known classical methods to test quantum circuits. Of course, classical fault models do not capture all the logical failures found in quantum circuits. The first obstacle faced when using methods from classical test is developing a set of realistic quantum-logical fault models. Developing fault models to abstract the test problem away from the device level motivated our study. Several results are established. First, we describe typical modes of failure present in the physical design of quantum circuits. From this we develop fault models for quantum binary circuits that enable testing at the logical level. The application of these fault models is shown by adapting the classical test set generation technique known as constructing a fault table to generate quantum test sets. A test set developed using this method is shown to detect each of the considered faults.

  6. Discrete Fracture Reservoir Simulation

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

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

  7. High temperature superconducting fault current limiter

    DOE Patents [OSTI]

    Hull, J.R.

    1997-02-04

    A fault current limiter for an electrical circuit is disclosed. The fault current limiter includes a high temperature superconductor in the electrical circuit. The high temperature superconductor is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter. 15 figs.

  8. High temperature superconducting fault current limiter

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL)

    1997-01-01

    A fault current limiter (10) for an electrical circuit (14). The fault current limiter (10) includes a high temperature superconductor (12) in the electrical circuit (14). The high temperature superconductor (12) is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter (10).

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

    SciTech Connect (OSTI)

    Gary Mavko

    2004-11-30

    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

  10. Wave Propagation in Fractured Poroelastic Media

    E-Print Network [OSTI]

    robiel

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

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

    SciTech Connect (OSTI)

    Robert Jacobi; John Fountain

    2002-06-30

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

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

    Open Energy Info (EERE)

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

  13. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, Jeffrey R.; Glaser, Steven D.

    2008-01-01

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

  14. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, J R; Glaser, Steven D

    2007-01-01

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

  15. The FRAC Act: The Fracturing Responsibility and

    E-Print Network [OSTI]

    Smerdon, Jason E.

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

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

    E-Print Network [OSTI]

    Ritchie, Robert

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

  17. 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

  18. Fracture of aluminum naval structures

    E-Print Network [OSTI]

    Galanis, Konstantinos, 1970-

    2007-01-01

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

  19. Sensitivity analysis of fracture scattering

    E-Print Network [OSTI]

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

    2010-01-01

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

  20. Use of outcrop analogues to predict lithology influence on the seismic signature Kathleen Baker* and Mike Batzle, Colorado School of Mines, Richard Gibson, Texas A&M University

    E-Print Network [OSTI]

    with outcrop studies, well log and seismic interpretation of deep-water sediments, forward and inverse modeling the interpretation of subsurface information such as well logs, seismic data and regional geologic models. Here we the influence of lithology on the seismic signature. Method To better interpret seismic DHIs it is essential

  1. Capillary fracture of soft gels

    E-Print Network [OSTI]

    Joshua B. Bostwick; Karen E. Daniels

    2013-10-16

    A liquid droplet resting on a soft gel substrate can deform that substrate to the point of material failure, whereby fractures develop on the gel surface that propagate outwards from the contact-line in a starburst pattern. In this paper, we characterize i) the initiation process in which the number of arms in the starburst is controlled by the ratio of surface tension contrast to the gel's elastic modulus and ii) the propagation dynamics showing that once fractures are initiated they propagate with a universal power law $L\\propto t^{3/4}$. We develop a model for crack initiation by treating the gel as a linear elastic solid and computing the deformations within the substrate from the liquid/solid wetting forces. The elastic solution shows that both the location and magnitude of the wetting forces are critical in providing a quantitative prediction for the number of fractures and, hence, an interpretation of the initiation of capillary fractures. This solution also reveals that the depth of the gel is an important factor in the fracture process, as it can help mitigate large surface tractions; this finding is confirmed with experiments. We then develop a model for crack propagation by considering the transport of an inviscid fluid into the fracture tip of an incompressible material, and find that a simple energy-conservation argument can explain the observed material-independent power law. We compare predictions for both linear elastic and neo-Hookean solids finding that the latter better explains the observed exponent.

  2. Fault-tolerant dynamic task graph scheduling

    SciTech Connect (OSTI)

    Kurt, Mehmet C.; Krishnamoorthy, Sriram; Agrawal, Kunal; Agrawal, Gagan

    2014-11-16

    In this paper, we present an approach to fault tolerant execution of dynamic task graphs scheduled using work stealing. In particular, we focus on selective and localized recovery of tasks in the presence of soft faults. We elicit from the user the basic task graph structure in terms of successor and predecessor relationships. The work stealing-based algorithm to schedule such a task graph is augmented to enable recovery when the data and meta-data associated with a task get corrupted. We use this redundancy, and the knowledge of the task graph structure, to selectively recover from faults with low space and time overheads. We show that the fault tolerant design retains the essential properties of the underlying work stealing-based task scheduling algorithm, and that the fault tolerant execution is asymptotically optimal when task re-execution is taken into account. Experimental evaluation demonstrates the low cost of recovery under various fault scenarios.

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

    E-Print Network [OSTI]

    Perll, Chris

    2013-12-31

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

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

    E-Print Network [OSTI]

    Ogbechie, Joachim Nwabunwanne

    2012-02-14

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

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

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    2011-01-01

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

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

    E-Print Network [OSTI]

    Zhang, Yang

    2005-01-01

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

  7. A fault location approach for fuzzy fault section estimation on radial distribution feeders 

    E-Print Network [OSTI]

    Andoh, Kwame Sarpong

    2000-01-01

    Locating the faulted section of a distribution system is a difficult task because of lack of accurate system models and the presence of uncertainty in the data used for estimating the fault section. Many of the methods used to account...

  8. Realistic fault modeling and quality test generation of combined delay faults 

    E-Print Network [OSTI]

    Thadhlani, Ajaykumar A

    2001-01-01

    With increasing operating speed and shrinking technology, timing defects in integrated circuits are becoming increasingly important. The well established stuck-at-fault model is not sufficient because it is a static fault model and does not account...

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

    E-Print Network [OSTI]

    Santos, Juan

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

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

    E-Print Network [OSTI]

    Narasimhan, T.N.

    2014-01-01

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

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

    SciTech Connect (OSTI)

    Potirakis, S. M.; Karadimitrakis, A.; Eftaxias, K.

    2013-06-15

    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.

  12. Earthquake Nucleation on Geometrically Complex Faults

    E-Print Network [OSTI]

    Fang, Zijun

    2009-01-01

    Preseismic fault slip and earthquake prediction, J. Geophys.Day, The 1999 Izmit, Turkey, earthquake: A 3D dynamic stresstransfer model of intra-earthquake triggering, Bull.

  13. Earthquake Nucleation on Geometrically Complex Faults

    E-Print Network [OSTI]

    Fang, Zijun

    2009-01-01

    fault slip and earthquake prediction, J. Geophys. Res. , [implications for an earthquake prediction field monitoringpredictions of hypocenter location and occurrence time of earthquakes,

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

    E-Print Network [OSTI]

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

    2000-01-01

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

  15. Accurate resistive bridge fault modeling, simulation, and test generation 

    E-Print Network [OSTI]

    Sar-Dessai, Vijay Ramesh

    1999-01-01

    Resistive bridging faults in CMOS combinational circuits are studied in this work. Bridging faults are modeled using HSPICE circuit simulation of the various types of bridging faults that can occur in CMOS combinational ...

  16. Earthquake behavior and structure of oceanic transform faults

    E-Print Network [OSTI]

    Roland, Emily Carlson

    2012-01-01

    Oceanic transform faults that accommodate strain at mid-ocean ridge offsets represent a unique environment for studying fault mechanics. Here, I use seismic observations and models to explore how fault structure affects ...

  17. Fault Intersection | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTIONRobertsdale, AlabamaETEC GmbHFarinello Geothermal Power Station JumpFaroeFaulk County,Fault

  18. Fault Mapping | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTIONRobertsdale, AlabamaETEC GmbHFarinello Geothermal Power Station JumpFaroeFaulk County,FaultMapping

  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

    2009-05-15

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

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

    E-Print Network [OSTI]

    Correa Castro, Juan

    2011-08-08

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

  1. Investigation of active faulting at the Emigrant Peak fault in Nevada using shallow seismic reflection and ground penetrating radar

    E-Print Network [OSTI]

    Christie, Michael Wayne

    2007-12-18

    The objective of this study was to assess fault displacement, off-fault deformation, and alluvial fan stratigraphy at the Emigrant Peak fault zone (EPFZ) in Fish Lake Valley, Nevada utilizing shallow seismic reflection (SSR) and ground penetrating...

  2. Evaluation of faulting characteristics and ground acceleration associated with recent movement along the Meers Fault, Southwestern Oklahoma 

    E-Print Network [OSTI]

    Burrell, Richard Dennis

    1997-01-01

    being cited as responsible for the Meers Fault scarp. Earthquakes of magnitude 7 to 8 occurring in conjunction with recent reactivation of the fault have been calculated. However, evidence found within the Wichita Mountains just south of the fault...

  3. Improving Distribution System Reliability Through Risk-base Doptimization of Fault Management and Improved Computer-based Fault Location 

    E-Print Network [OSTI]

    Dong, Yimai

    2013-11-07

    regulation on power quality. Optimization in fault management tasks has the potential of improving system reliability by reducing the duration and scale of outages caused by faults through fast fault isolation and service restoration. The research reported...

  4. PERSPECTIVES Deep Earthquakes: A Fault Too Big?

    E-Print Network [OSTI]

    Stein, Seth

    PERSPECTIVES Deep Earthquakes: A Fault Too Big? Seth Stein Because deep Earth processes are inacces. Recent results for the mys- terious deep earthquakes that occur to depths greater than 600 km is that large deep earthquakes (1-3) seem to have occurred on faults larger than ex- pected from the competing

  5. INDUCTION MOTOR FAULT DIAGNOSTIC AND MONITORING METHODS

    E-Print Network [OSTI]

    Povinelli, Richard J.

    INDUCTION MOTOR FAULT DIAGNOSTIC AND MONITORING METHODS by Aderiano M. da Silva, B.S. A Thesis;i Abstract Induction motors are used worldwide as the "workhorse" in industrial applications material. However, induction motor faults can be detected in an initial stage in order to prevent

  6. Sensor Fault Diagnosis Using Principal Component Analysis 

    E-Print Network [OSTI]

    Sharifi, Mahmoudreza

    2010-07-14

    The purpose of this research is to address the problem of fault diagnosis of sensors which measure a set of direct redundant variables. This study proposes: 1. A method for linear senor fault diagnosis 2. An analysis of isolability and detectability...

  7. Detailed Geophysical Fault Characterization in Yucca Flat, Nevada Test Site, Nevada

    SciTech Connect (OSTI)

    Theodore H. Asch; Donald Sweetkind; Bethany L. Burton; Erin L. Wallin

    2009-02-10

    Yucca Flat is a topographic and structural basin in the northeastern part of the Nevada Test Site (NTS) in Nye County, Nevada. Between the years 1951 and 1992, 659 underground nuclear tests took place in Yucca Flat; most were conducted in large, vertical excavations that penetrated alluvium and the underlying Cenozoic volcanic rocks. Radioactive and other potential chemical contaminants at the NTS are the subject of a long-term program of investigation and remediation by the U.S. Department of Energy (DOE), National Nuclear Security Administration, Nevada Site Office, under its Environmental Restoration Program. As part of the program, the DOE seeks to assess the extent of contamination and to evaluate the potential risks to humans and the environment from byproducts of weapons testing. To accomplish this objective, the DOE Environmental Restoration Program is constructing and calibrating a ground-water flow model to predict hydrologic flow in Yucca Flat as part of an effort to quantify the subsurface hydrology of the Nevada Test Site. A necessary part of calibrating and evaluating a model of the flow system is an understanding of the location and characteristics of faults that may influence ground-water flow. In addition, knowledge of fault-zone architecture and physical properties is a fundamental component of the containment of the contamination from underground nuclear tests, should such testing ever resume at the Nevada Test Site. The goal of the present investigation is to develop a detailed understanding of the geometry and physical properties of fault zones in Yucca Flat. This study was designed to investigate faults in greater detail and to characterize fault geometry, the presence of fault splays, and the fault-zone width. Integrated geological and geophysical studies have been designed and implemented to work toward this goal. This report describes the geophysical surveys conducted near two drill holes in Yucca Flat, the data analyses performed, and the integrated interpretations developed from the suite of geophysical methodologies utilized in this investigation. Data collection for this activity started in the spring of 2005 and continued into 2006. A suite of electrical geophysical surveys were run in combination with ground magnetic surveys; these surveys resulted in high-resolution subsurface data that portray subsurface fault geometry at the two sites and have identified structures not readily apparent from surface geologic mapping, potential field geophysical data, or surface effects fracture maps.

  8. Physiochemical Evidence of Faulting Processes and Modeling of Fluid in Evolving Fault Systems in Southern California

    SciTech Connect (OSTI)

    Boles, James [Professor

    2013-05-24

    Our study targets recent (Plio-Pleistocene) faults and young (Tertiary) petroleum fields in southern California. Faults include the Refugio Fault in the Transverse Ranges, the Ellwood Fault in the Santa Barbara Channel, and most recently the Newport- Inglewood in the Los Angeles Basin. Subsurface core and tubing scale samples, outcrop samples, well logs, reservoir properties, pore pressures, fluid compositions, and published structural-seismic sections have been used to characterize the tectonic/diagenetic history of the faults. As part of the effort to understand the diagenetic processes within these fault zones, we have studied analogous processes of rapid carbonate precipitation (scaling) in petroleum reservoir tubing and manmade tunnels. From this, we have identified geochemical signatures in carbonate that characterize rapid CO2 degassing. These data provide constraints for finite element models that predict fluid pressures, multiphase flow patterns, rates and patterns of deformation, subsurface temperatures and heat flow, and geochemistry associated with large fault systems.

  9. Method for directional hydraulic fracturing

    DOE Patents [OSTI]

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

    1994-01-01

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

  10. Self-triggering superconducting fault current limiter

    DOE Patents [OSTI]

    Yuan, Xing (Albany, NY); Tekletsadik, Kasegn (Rexford, NY)

    2008-10-21

    A modular and scaleable Matrix Fault Current Limiter (MFCL) that functions as a "variable impedance" device in an electric power network, using components made of superconducting and non-superconducting electrically conductive materials. The matrix fault current limiter comprises a fault current limiter module that includes a superconductor which is electrically coupled in parallel with a trigger coil, wherein the trigger coil is magnetically coupled to the superconductor. The current surge doing a fault within the electrical power network will cause the superconductor to transition to its resistive state and also generate a uniform magnetic field in the trigger coil and simultaneously limit the voltage developed across the superconductor. This results in fast and uniform quenching of the superconductors, significantly reduces the burnout risk associated with non-uniformity often existing within the volume of superconductor materials. The fault current limiter modules may be electrically coupled together to form various "n" (rows).times."m" (columns) matrix configurations.

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

    E-Print Network [OSTI]

    Pruess, K.

    2010-01-01

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

  12. Harmonic experiments to model fracture induced anisotropy

    E-Print Network [OSTI]

    Santos, Juan

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

  13. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, Jeffrey R.; Glaser, Steven D.

    2008-01-01

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

  14. Modeling of Acid Fracturing in Carbonate Reservoirs 

    E-Print Network [OSTI]

    Al Jawad, Murtada s

    2014-06-05

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

  15. Lisburne Formation fracture characterization and flow modeling 

    E-Print Network [OSTI]

    Karpov, Alexandre Valerievich

    2001-01-01

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

  16. Acoustic Character Of Hydraulic Fractures In Granite

    E-Print Network [OSTI]

    Paillet, Frederick I.

    1983-01-01

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

  17. 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

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

    E-Print Network [OSTI]

    Grujicic, Mica

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

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

    E-Print Network [OSTI]

    Ritchie, Robert

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

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

    E-Print Network [OSTI]

    Espinosa, Horacio D.

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

  1. 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

  2. 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

  3. Identifying Best Practices in Hydraulic Fracturing Using

    E-Print Network [OSTI]

    Mohaghegh, Shahab

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

  4. 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

  5. FRACTURE TOUGHNESS OF WOOD AND WOOD COMPOSITES

    E-Print Network [OSTI]

    Nairn, John A.

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

  6. Models for MetaVCeramic Interface Fracture

    E-Print Network [OSTI]

    Suo, Zhigang

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

  7. FRACTURE IN DISORDERED BRITTLE MEDIA A Dissertation

    E-Print Network [OSTI]

    Sethna, James P.

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

  8. Presented by Statistical Physics of Fracture

    E-Print Network [OSTI]

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

  9. Image-Guided Fracture David Mould

    E-Print Network [OSTI]

    Mould, David

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

  10. Sensitivity analysis of fracture scattering

    E-Print Network [OSTI]

    Fang, Xinding

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

  11. 3-D RESERVOIR AND STOCHASTIC FRACTURE NETWORK MODELING FOR ENHANCED OIL RECOVERY, CIRCLE RIDGE PHOSPHORIA/TENSLEEP RESERVOIR, WIND RIVER RESERVATION, ARAPAHO AND SHOSHONE TRIBES, WYOMING

    SciTech Connect (OSTI)

    Paul La Pointe; Jan Hermanson; Robert Parney; Thorsten Eiben; Mike Dunleavy; Ken Steele; John Whitney; Darrell Eubanks; Roger Straub

    2002-11-18

    This report describes the results made in fulfillment of contract DE-FG26-00BC15190, ''3-D Reservoir and Stochastic Fracture Network Modeling for Enhanced Oil Recovery, Circle Ridge Phosphoria/Tensleep Reservoir, Wind River Reservation, Arapaho and Shoshone Tribes, Wyoming''. The goal of this project is to improve the recovery of oil from the Tensleep and Phosphoria Formations in Circle Ridge Oilfield, located on the Wind River Reservation in Wyoming, through an innovative integration of matrix characterization, structural reconstruction, and the characterization of the fracturing in the reservoir through the use of discrete fracture network models. Fields in which natural fractures dominate reservoir permeability, such as the Circle Ridge Field, often experience sub-optimal recovery when recovery processes are designed and implemented that do not take advantage of the fracture systems. For example, a conventional waterflood in a main structural block of the Field was implemented and later suspended due to unattractive results. It is estimated that somewhere less than 20% of the OOIP in the Circle Ridge Field have been recovered after more than 50 years' production. Marathon Oil Company identified the Circle Ridge Field as an attractive candidate for several advanced IOR processes that explicitly take advantage of the natural fracture system. These processes require knowledge of the distribution of matrix porosity, permeability and oil saturations; and understanding of where fracturing is likely to be well-developed or poorly developed; how the fracturing may compartmentalize the reservoir; and how smaller, relatively untested subthrust fault blocks may be connected to the main overthrust block. For this reason, the project focused on improving knowledge of the matrix properties, the fault block architecture and to develop a model that could be used to predict fracture intensity, orientation and fluid flow/connectivity properties. Knowledge of matrix properties was greatly extended by calibrating wireline logs from 113 wells with incomplete or older-vintage logging suites to wells with a full suite of modern logs. The model for the fault block architecture was derived by 3D palinspastic reconstruction. This involved field work to construct three new cross-sections at key areas in the Field; creation of horizon and fault surface maps from well penetrations and tops; and numerical modeling to derive the geometry, chronology, fault movement and folding history of the Field through a 3D restoration of the reservoir units to their original undeformed state. The methodology for predicting fracture intensity and orientation variations throughout the Field was accomplished by gathering outcrop and subsurface image log fracture data, and comparing it to the strain field produced by the various folding and faulting events determined through the 3D palinspastic reconstruction. It was found that the strains produced during the initial folding of the Tensleep and Phosphoria Formations corresponded well without both the orientations and relative fracture intensity measured in outcrop and in the subsurface. The results have led to a 15% to 20% increase in estimated matrix pore volume, and to the plan to drill two horizontal drain holes located and oriented based on the modeling results. Marathon Oil is also evaluating alternative tertiary recovery processes based on the quantitative 3D integrated reservoir model.

  12. Mechanical Models of Fault-Related Folding

    SciTech Connect (OSTI)

    Johnson, A. M.

    2003-01-09

    The subject of the proposed research is fault-related folding and ground deformation. The results are relevant to oil-producing structures throughout the world, to understanding of damage that has been observed along and near earthquake ruptures, and to earthquake-producing structures in California and other tectonically-active areas. The objectives of the proposed research were to provide both a unified, mechanical infrastructure for studies of fault-related foldings and to present the results in computer programs that have graphical users interfaces (GUIs) so that structural geologists and geophysicists can model a wide variety of fault-related folds (FaRFs).

  13. Fault-Tolerant Exact State Transmission

    E-Print Network [OSTI]

    Zhao-Ming Wang; Lian-Ao Wu; Michele Modugno; Wang Yao; Bin Shao

    2012-05-02

    We show that a category of one-dimensional XY-type models may enable high-fidelity quantum state transmissions, regardless of details of coupling configurations. This observation leads to a fault- tolerant design of a state transmission setup. The setup is fault-tolerant, with specified thresholds, against engineering failures of coupling configurations, fabrication imperfections or defects, and even time-dependent noises. We propose the implementation of the fault-tolerant scheme using hard-core bosons in one-dimensional optical lattices.

  14. Cooperative application/OS DRAM fault recovery.

    SciTech Connect (OSTI)

    Ferreira, Kurt Brian; Bridges, Patrick G. (University of New Mexico, Albuquerque, NM); Heroux, Michael Allen; Hoemmen, Mark; Brightwell, Ronald Brian

    2012-05-01

    Exascale systems will present considerable fault-tolerance challenges to applications and system software. These systems are expected to suffer several hard and soft errors per day. Unfortunately, many fault-tolerance methods in use, such as rollback recovery, are unsuitable for many expected errors, for example DRAM failures. As a result, applications will need to address these resilience challenges to more effectively utilize future systems. In this paper, we describe work on a cross-layer application/OS framework to handle uncorrected memory errors. We illustrate the use of this framework through its integration with a new fault-tolerant iterative solver within the Trilinos library, and present initial convergence results.

  15. Fault Detection and Diagnosis in Building HVAC Systems

    E-Print Network [OSTI]

    Najafi, Massieh

    2010-01-01

    of outside air condition, occupant behavior, and buildingair condition and occupant behavior) and fault condition (

  16. RESEARCH PROGRAM ON FRACTURED PETROLEUM RESERVOIRS

    SciTech Connect (OSTI)

    Abbas Firoozabadi

    2002-04-12

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

  17. Fracture-permeability behavior of shale

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

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

    2015-05-08

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

  18. Fracture-permeability behavior of shale

    SciTech Connect (OSTI)

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

    2015-05-08

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

  19. Interaction between Injection Points during Hydraulic Fracturing

    E-Print Network [OSTI]

    Hals, Kjetil M D

    2012-01-01

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

  20. Conditions during syntectonic vein formation in the footwall of the Absaroka thrust fault of the Idaho-Wyoming-Utah fold and thrust belt 

    E-Print Network [OSTI]

    Lambert, George Randall

    1993-01-01

    Results. . Isotope Thermometry . FRACTURE MECHANICS . Analysis Procedure and Results DISCUSSION . Thrust Faulting and Overburden Temperatures. Geothermal Gradient Constraints. Twtn Creek Formation Fluid Flow? Closed system. Open System. . tv vt...C. The lithostatic and hydrostatic thermobartc gradients were calculated using a 26 MPa/km hthostatic gradient, a 10 MPa/km hydrostatic gradient and a 25oC/km geothermal gradient. The present mean surface temperature in this portion of the Idaho-Wyoming-Utah fold...

  1. Permeability Calculation in a Fracture Network - 12197

    SciTech Connect (OSTI)

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

    2012-07-01

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

  2. Initiation of the San Jacinto Fault and its Interaction with the San Andreas Fault: Insights from Geodynamic Modeling

    E-Print Network [OSTI]

    Liu, Mian

    Initiation of the San Jacinto Fault and its Interaction with the San Andreas Fault: Insights from Geodynamic Modeling QINGSONG LI 1,2 and MIAN LIU 1 Abstract--The San Andreas Fault (SAF) is the Pacific is accommodated by the San Jacinto Fault (SJF). Here we investigate the initiation of the SJF and its interaction

  3. 1. Detect ground faults in PV arrays mounted on the roofs of 2. Interrupt the fault current

    E-Print Network [OSTI]

    Johnson, Eric E.

    1. Detect ground faults in PV arrays mounted on the roofs of dwellings 2. Interrupt the fault current 3. Indicate that a ground fault had occurred 4. Disconnect the faulted part of the PV array 5. "Crowbar" (short-circuit) the PV array The original GFPD prototype was developed in two versions that were

  4. The propagation and linkage of normal faults: Insights from the Strathspey-Brent-Statfjord fault array, northern North Sea

    E-Print Network [OSTI]

    McLeod, Aileen E.

    2001-01-01

    Through examination of the scaling relations of faults and the use of seismic stratigraphic techniques,

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

    E-Print Network [OSTI]

    Wang, J.S.Y.

    2013-01-01

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

  6. Structure of the eastern Red Rocks and Wind Ridge thrust faults, Wyoming: how a thrust fault gains displacement along strike 

    E-Print Network [OSTI]

    Huntsman, Brent Stanley

    1983-01-01

    OF FIELD MAPPING Methods . Thrust Faults . The Wind Ridge Thrust Fault System The Red Rocks Thrust Fault System CLAY MODEL STUDIES Purpose and Description Model Results DISCUSSION OF RESULTS Kinematics of the Red Rocks Thrust Fault Termination... . Kinematics of the Southern Wind Ridge Thrust Fault . . . A Conceptual Model of the Red Rocks Thrust Fault Termination Implications of the Red Rocks Fault Termination . . . . . . Page V1 V11 1X X1 X11 7 9 17 18 18 21 24 27 35 35 38 49 49...

  7. A connecting network with fault tolerance capabilities

    SciTech Connect (OSTI)

    Ciminiera, L.; Serra, A.

    1986-06-01

    A new multistage interconnection network is presented in this paper. It is able to handle the communications between the connected devices correctly, even in the presence of fault(s) in the network. This goal is achieved by using redundant paths with a fast procedure able to dynamically reroute the message. It is also shown that the rerouting properties are still valid when broadcasting transmission is used.

  8. The Statistical Reservoir Model: calibrating faults and fractures, and predicting reservoir response to water flood

    E-Print Network [OSTI]

    geomechanics to have a significant influence on hydrocarbon production rates through changes in the effective 2004). Geomechanics not only predicts a reservoir response in the near field, but also at long range i

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

    E-Print Network [OSTI]

    Pieve La Rosa, Andres Eduardo

    2011-08-08

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

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

    E-Print Network [OSTI]

    Nelson, J.T.

    2009-01-01

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

  11. GEOLOGIC NOTE Fault linkage and graben

    E-Print Network [OSTI]

    Fossen, Haakon

    . Schultz $ Geomechanics-Rock Fracture Group, Department of Geological Sciences and Engineering/172 (1982), and his Ph.D. in geomechanics from Purdue University (1987). He worked at the Lunar

  12. Layer thickness and the shape of faults A. Benedicto

    E-Print Network [OSTI]

    . Paris XI, France R. A. Schultz Dept. Geological Sciences, Geomechanics-Rock Fracture Group, Mackay

  13. Fault-tolerant Sensor Network based on Fault Evaluation Matrix and Compensation for Intermittent Observation

    E-Print Network [OSTI]

    Fault-tolerant Sensor Network based on Fault Evaluation Matrix and Compensation for Intermittent-tolerant sensor network configuration problem for a target navigation. A sensor network system consists of many sensor nodes and its network connections. Each sensor node can exchange information by wireless

  14. Realization of User Level Fault Tolerant Policy Management through a Holistic Approach for Fault Correlation

    SciTech Connect (OSTI)

    Park, Byung H [ORNL; Naughton, III, Thomas J [ORNL; Agarwal, Pratul K [ORNL; Bernholdt, David E [ORNL; Geist, Al [ORNL; Tippens, Jennifer L [ORNL

    2011-01-01

    Many modern scientific applications, which are designed to utilize high performance parallel com- puters, occupy hundreds of thousands of computational cores running for days or even weeks. Since many scien- tists compete for resources, most supercomputing centers practice strict scheduling policies and perform meticulous accounting on their usage. Thus computing resources and time assigned to a user is considered invaluable. However, most applications are not well prepared for un- foreseeable faults, still relying on primitive fault tolerance techniques. Considering that ever-plunging mean time to interrupt (MTTI) is making scientific applications more vulnerable to faults, it is increasingly important to provide users not only an improved fault tolerant environment, but also a framework to support their own fault tolerance policies so that their allocation times can be best utilized. This paper addresses a user level fault tolerance policy management based on a holistic approach to digest and correlate fault related information. It introduces simple semantics with which users express their policies on faults, and illustrates how event correlation techniques can be applied to manage and determine the most preferable user policies. The paper also discusses an implementation of the framework using open source software, and demonstrates, as an example, how a molecular dynamics simulation application running on the institutional cluster at Oak Ridge National Laboratory benefits from it.

  15. Measuring and Modeling Fault Density for Plume-Fault Encounter Probability Estimation

    SciTech Connect (OSTI)

    Jordan, P.D.; Oldenburg, C.M.; Nicot, J.-P.

    2011-05-15

    Emission of carbon dioxide from fossil-fueled power generation stations contributes to global climate change. Storage of this carbon dioxide within the pores of geologic strata (geologic carbon storage) is one approach to mitigating the climate change that would otherwise occur. The large storage volume needed for this mitigation requires injection into brine-filled pore space in reservoir strata overlain by cap rocks. One of the main concerns of storage in such rocks is leakage via faults. In the early stages of site selection, site-specific fault coverages are often not available. This necessitates a method for using available fault data to develop an estimate of the likelihood of injected carbon dioxide encountering and migrating up a fault, primarily due to buoyancy. Fault population statistics provide one of the main inputs to calculate the encounter probability. Previous fault population statistics work is shown to be applicable to areal fault density statistics. This result is applied to a case study in the southern portion of the San Joaquin Basin with the result that the probability of a carbon dioxide plume from a previously planned injection had a 3% chance of encountering a fully seal offsetting fault.

  16. Fault Detection and Load Distribution for the Wind Farm Challenge

    SciTech Connect (OSTI)

    Borchehrsen, Anders B.; Larsen, Jesper A.; Stoustrup, Jakob

    2014-08-24

    In this paper a fault detection system and a fault tolerant controller for a wind farm model. The wind farm model used is the one proposed as a public challenge. In the model three types of faults are introduced to a wind farm consisting of nine turbines. A fault detection system designed, by taking advantage of the fact that within a wind farm several wind turbines will be operating under all most identical conditions. The turbines are then grouped, and then turbines within each group are used to generate residuals for turbines in the group. The generated residuals are then evaluated using dynamical cumulative sum. The designed fault detection system is cable of detecting all three fault types occurring in the model. But there is room for improving the fault detection in some areas. To take advantage of the fault detection system a fault tolerant controller for the wind farm has been designed. The fault tolerant controller is a dispatch controller which is estimating the possible power at each individual turbine and then setting the reference accordingly. The fault tolerant controller has been compared to a reference controller. And the comparison shows that the fault tolerant controller performance better in all measures. The fault detection and a fault tolerant controller has been designed, and based on the simulated results the overall performance of the wind farm is improved on all measures. Thereby this is a step towards improving the overall performance of current and future wind farms.

  17. Apparatus and method for monitoring underground fracturing

    DOE Patents [OSTI]

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

    1999-08-10

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

  18. Apparatus and method for monitoring underground fracturing

    DOE Patents [OSTI]

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

    1999-08-10

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

  19. Fault Locating, Prediction and Protection (FLPPS)

    SciTech Connect (OSTI)

    Yinger, Robert, J.; Venkata, S., S.; Centeno, Virgilio

    2010-09-30

    One of the main objectives of this DOE-sponsored project was to reduce customer outage time. Fault location, prediction, and protection are the most important aspects of fault management for the reduction of outage time. In the past most of the research and development on power system faults in these areas has focused on transmission systems, and it is not until recently with deregulation and competition that research on power system faults has begun to focus on the unique aspects of distribution systems. This project was planned with three Phases, approximately one year per phase. The first phase of the project involved an assessment of the state-of-the-art in fault location, prediction, and detection as well as the design, lab testing, and field installation of the advanced protection system on the SCE Circuit of the Future located north of San Bernardino, CA. The new feeder automation scheme, with vacuum fault interrupters, will limit the number of customers affected by the fault. Depending on the fault location, the substation breaker might not even trip. Through the use of fast communications (fiber) the fault locations can be determined and the proper fault interrupting switches opened automatically. With knowledge of circuit loadings at the time of the fault, ties to other circuits can be closed automatically to restore all customers except the faulted section. This new automation scheme limits outage time and increases reliability for customers. The second phase of the project involved the selection, modeling, testing and installation of a fault current limiter on the Circuit of the Future. While this project did not pay for the installation and testing of the fault current limiter, it did perform the evaluation of the fault current limiter and its impacts on the protection system of the Circuit of the Future. After investigation of several fault current limiters, the Zenergy superconducting, saturable core fault current limiter was selected for installation. Because of some testing problems with the Zenergy fault current limiter, installation was delayed until early 2009 with it being put into operation on March 6, 2009. A malfunction of the FCL controller caused the DC power supply to the superconducting magnet to be turned off. This inserted the FCL impedance into the circuit while it was in normal operation causing a voltage resonance condition. While these voltages never reached a point where damage would occur on customer equipment, steps were taken to insure this would not happen again. The FCL was reenergized with load on December 18, 2009. A fault was experienced on the circuit with the FCL in operation on January 14, 2010. The FCL operated properly and reduced the fault current by about 8%, what was expected from tests and modeling. As of the end of the project, the FCL was still in operation on the circuit. The third phase of the project involved the exploration of several advanced protection ideas that might be at a state where they could be applied to the Circuit of the Future and elsewhere in the SCE electrical system. Based on the work done as part of the literature review and survey, as well as a number of internal meetings with engineering staff at SCE, a number of ideas were compiled. These ideas were then evaluated for applicability and ability to be applied on the Circuit of the Future in the time remaining for the project. Some of these basic ideas were implemented on the circuit including measurement of power quality before and after the FCL. It was also decided that we would take what was learned as part of the Circuit of the Future work and extend it to the next generation circuit protection for SCE. Also at this time, SCE put in a proposal to the DOE for the Irvine Smart Grid Demonstration using ARRA funding. SCE was successful in obtaining funding for this proposal, so it was felt that exploration of new protection schemes for this Irvine Smart Grid Demonstration would be a good use of the project resources. With this in mind, a protection system that uses fault interrupting switches, hi

  20. Are Carotid Stent Fractures Clinically Significant?

    SciTech Connect (OSTI)

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

    2012-04-15

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

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

    E-Print Network [OSTI]

    Berthelot, Jan Marie

    1990-01-01

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

  2. Mechanical properties and modeling of seal-forming lithologies. Technical progress report No. 3, March 15, 1992--June 14, 1993

    SciTech Connect (OSTI)

    Kronenberg, A.K.; Russell, J.E.; Carter, N.L.; Mazariegos, R.; Ibanez, W.

    1993-06-01

    Specific goals and accomplishments of this research include: (1) The evaluation of models of salt diaper ascent that involve either power law, dislocation creep as determined experimentally by Horseman et al. (1993) or linear, fluid-assisted creep as reported by Spiers et al. (1988, 1990, 1992). We have compared models assuming these two, experimentally evaluated flow laws and examined the predictions they make regarding diaper incubation periods, ascent velocities, deviatoric stresses and strain rates. (2) The evaluation of the effects of differential loading on the initiation an of salt structures. (3) Examination of the role of basement faults on the initiation and morphologic evolution of salt structures. (4) Evaluation of the mechanical properties of shale as a function of pressure and determination of the nature of its brittle-ductile transition. (5) Evaluation of the mechanical anisotropies of shales with varying concentrations, distributions and preferred orientations of clay. (6) The determination of temperature and ratedependencies of strength for a shale constitutive model that can be used in numerical models that depend on viscous formulations. (7) Determination of the mechanisms of deformation for argillaceous rocks over awide range of conditions. (8) Evaluation of the effects of H{sub 2}O within clay interlayers, as adsorbed surface layers.

  3. Method of fracturing a geological formation

    DOE Patents [OSTI]

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

    1990-01-01

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

  4. Hydraulic Fracturing Poster | Department of Energy

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

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

  5. A compendium of fracture flow models, 1994

    SciTech Connect (OSTI)

    Diodato, D.M.

    1994-11-01

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

  6. 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...

  7. 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...

  8. The Influence of fold and fracture development on reservoir behavior of the Lisburne Group of northern Alaska

    SciTech Connect (OSTI)

    Wesley K. Wallace; Catherine L. Hanks; Jerry Jensen: Michael T. Whalen; Paul Atkinson; Joseph Brinton; Thang Bui; Margarete Jadamec; Alexandre Karpov; John Lorenz; Michelle M. McGee; T.M. Parris; Ryan Shackleton

    2004-07-01

    The Carboniferous Lisburne Group is a major carbonate reservoir unit in northern Alaska. The Lisburne is folded and thrust faulted where it is exposed throughout the Brooks Range, but is relatively undeformed in areas of current production in the subsurface of the North Slope. The objectives of this study were to develop a better understanding of four major aspects of the Lisburne: (1) The geometry and kinematics of folds and their truncation by thrust faults. (2) The influence of folding on fracture patterns. (3) The influence of deformation on fluid flow. (4) Lithostratigraphy and its influence on folding, faulting, fracturing, and reservoir characteristics. Symmetrical detachment folds characterize the Lisburne in the northeastern Brooks Range. In contrast, Lisburne in the main axis of the Brooks Range is deformed into imbricate thrust sheets with asymmetrical hangingwall anticlines and footwall synclines. The Continental Divide thrust front separates these different structural styles in the Lisburne and also marks the southern boundary of the northeastern Brooks Range. Field studies were conducted for this project during 1999 to 2001 in various locations in the northeastern Brooks Range and in the vicinity of Porcupine Lake, immediately south of the Continental Divide thrust front. Results are summarized below for the four main subject areas of the study.

  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. Characterization of dipping fractures in transversely isotropic background

    E-Print Network [OSTI]

    Tsvankin, Ilya

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

  11. Incorporating Rigorous Height Determination into Unified Fracture Design 

    E-Print Network [OSTI]

    Pitakbunkate, Termpan

    2010-10-12

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

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

    E-Print Network [OSTI]

    Xiang, Jing

    2012-02-14

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

  13. FINITE FRACTURE MECHANICS OF MATRIX MICROCRACKING IN COMPOSITES

    E-Print Network [OSTI]

    Nairn, John A.

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

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

    E-Print Network [OSTI]

    Zheng, Yingcai

    2012-01-01

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

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

    E-Print Network [OSTI]

    Xue, Liang, 1973-

    2007-01-01

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

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

    E-Print Network [OSTI]

    Cai, Wei

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

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

    E-Print Network [OSTI]

    Rahman, Sharif

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

  18. UNIVERSITY OF CALGARY Modeling Fracture Formation on Growing Surfaces

    E-Print Network [OSTI]

    Prusinkiewicz, Przemyslaw

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

  19. Faulted joints: kinematics, displacementlength scaling relations and criteria for their identication

    E-Print Network [OSTI]

    Engelder, Terry

    and kinematics based on two sets of joints, pinnate joints and fault striations, reveal that some mesoscale faults (i.e., faults without linked fault segments) at the mesoscale: ªneoformed faultsº which form

  20. A Hybrid Model Based and Statistical Fault Diagnosis System for Industrial Process 

    E-Print Network [OSTI]

    Lin, Chen-Han

    2014-11-21

    This thesis presents a hybrid model based and statistical fault diagnosis system, which applied on the nonlinear three-tank model. The purpose of fault diagnosis is generating and analyzing the residual to find out the fault occurrence. This fault...

  1. VCSEL fault location apparatus and method

    DOE Patents [OSTI]

    Keeler, Gordon A. (Albuquerque, NM); Serkland, Darwin K. (Albuquerque, NM)

    2007-05-15

    An apparatus for locating a fault within an optical fiber is disclosed. The apparatus, which can be formed as a part of a fiber-optic transmitter or as a stand-alone instrument, utilizes a vertical-cavity surface-emitting laser (VCSEL) to generate a test pulse of light which is coupled into an optical fiber under test. The VCSEL is subsequently reconfigured by changing a bias voltage thereto and is used as a resonant-cavity photodetector (RCPD) to detect a portion of the test light pulse which is reflected or scattered from any fault within the optical fiber. A time interval .DELTA.t between an instant in time when the test light pulse is generated and the time the reflected or scattered portion is detected can then be used to determine the location of the fault within the optical fiber.

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

    E-Print Network [OSTI]

    Tao, Qingfeng

    2010-07-14

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

  3. Fault-tolerant three-level inverter

    DOE Patents [OSTI]

    Edwards, John; Xu, Longya; Bhargava, Brij B.

    2006-12-05

    A method for driving a neutral point clamped three-level inverter is provided. In one exemplary embodiment, DC current is received at a neutral point-clamped three-level inverter. The inverter has a plurality of nodes including first, second and third output nodes. The inverter also has a plurality of switches. Faults are checked for in the inverter and predetermined switches are automatically activated responsive to a detected fault such that three-phase electrical power is provided at the output nodes.

  4. Development of a bridge fault extractor tool 

    E-Print Network [OSTI]

    Bhat, Nandan D.

    2005-02-17

    are tools that analyze chip layouts and produce a realistic list of bridging faults within that chip. FedEx, previously developed at Texas A&M University, extracts all two-node intralayer bridges of any given chip layout and optionally extracts all two...) for this tool which aids in more effectively visualizing the bridge faults across the chip. The final aim of this thesis was to perform FedEx output analysis to understand the nature of the defects, such as variation of critical area (the area where...

  5. Motivation Methodology Conclusions A Fault Tolerance Bisimulation Proof for

    E-Print Network [OSTI]

    Francalanza, Adrian

    Motivation Methodology Conclusions A Fault Tolerance Bisimulation Proof for Consensus Adrian of Somewhere and Elsewhere A Fault Tolerance Bisimulation Proof for Consensus #12;Motivation Methodology Conclusions Outline 1 Motivation 2 Methodology 3 Conclusions Adrian Francalanza, Matthew Hennessy Universities

  6. Upper crustal faulting in an obliquely extending orogen, structural...

    Open Energy Info (EERE)

    field in the central Coso Range, eastern California, image brittle faults and other structures in a zone of localized crustal extension between two major strike-slip faults. The...

  7. Occupancy Based Fault Detection on Building Level - a Feasibility Study 

    E-Print Network [OSTI]

    Tuip, B.; Houten, M.; Trcka, M.; Hensen, M.

    2010-01-01

    -line, self learning fault detection tool on building level. Taking passive user behavior into account, the tool aims to distinguish real faults from unexpected user behavior. An artificial neural network model is used to predict building energy consumption...

  8. Two Similarity Measure Approaches to Whole Building Fault Diagnosis 

    E-Print Network [OSTI]

    Lin, G.; Claridge, D.

    2012-01-01

    similarity are defined and the methodology for implementing the proposed whole building fault diagnosis approaches is presented. Cosine similarity and Euclidean distance similarity are applied to two field observed fault test cases, and both the cosine...

  9. Dining philosophers with masking tolerance to crash faults 

    E-Print Network [OSTI]

    Idimadakala, Vijaya K.

    2009-05-15

    We examine the tolerance of dining philosopher algorithms subject to process crash faults in arbitrary conflict graphs. This classic problem is unsolvable in asynchronous message-passing systems subject to even a single crash fault. By contrast...

  10. Synthesis and evaluation of fault-tolerant quantum computer architectures

    E-Print Network [OSTI]

    Cross, Andrew W. (Andrew William), 1979-

    2005-01-01

    Fault-tolerance is the cornerstone of practical, large-scale quantum computing, pushed into its prominent position with heroic theoretical efforts. The fault-tolerance threshold, which is the component failure probability ...

  11. Development of a Hydrologic Characterization Technology for Fault Zones Final Report

    E-Print Network [OSTI]

    Karasaki, Kenzi

    2014-01-01

    times by triggering a GFCI (Ground Fault Circuit Interrupt).time, rain caused a GFCI (ground fault circuit interrupt),

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

    E-Print Network [OSTI]

    Rutqvist, J.

    2011-01-01

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

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

    E-Print Network [OSTI]

    Cotte, F.P.

    2012-01-01

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

  14. 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...

  15. Images of Fracture Sustainability Test on Stripa Granite

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

    Tim Kneafsey

    2014-05-11

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

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

    Office of Scientific and Technical Information (OSTI)

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

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

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

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

  18. 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.

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

    E-Print Network [OSTI]

    Perez Garcia, Laura Elena

    2006-04-12

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

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

    Office of Scientific and Technical Information (OSTI)

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

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

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

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

  2. Elastic properties of saturated porous rocks with aligned fractures

    E-Print Network [OSTI]

    2003-12-02

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

  3. Irradiation Effects on Human Cortical Bone Fracture Behavior

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

    Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking...

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

    Office of Scientific and Technical Information (OSTI)

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

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

    E-Print Network [OSTI]

    Guo, Dongning

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

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

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

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

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

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

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

  8. Irradiation Effects on Human Cortical Bone Fracture Behavior

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

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

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

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

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

  10. Fault-Tolerant Non-interference Extended Version

    E-Print Network [OSTI]

    Russo, Alejandro

    a fault (induced by holding a light-bulb near the processor!) triggers a single bit flip in a malicious

  11. Adjustable direct current and pulsed circuit fault current limiter

    DOE Patents [OSTI]

    Boenig, Heinrich J.; Schillig, Josef B.

    2003-09-23

    A fault current limiting system for direct current circuits and for pulsed power circuit. In the circuits, a current source biases a diode that is in series with the circuits' transmission line. If fault current in a circuit exceeds current from the current source biasing the diode open, the diode will cease conducting and route the fault current through the current source and an inductor. This limits the rate of rise and the peak value of the fault current.

  12. Detachment Faulting & Geothermal Resources- Pearl Hot Spring, NV

    Broader source: Energy.gov [DOE]

    Detachment Faulting & Geothermal Resources - Pearl Hot Spring, NV presentation at the April 2013 peer review meeting held in Denver, Colorado.

  13. Fracture of solid state laser slabs

    SciTech Connect (OSTI)

    Marion, J.E.

    1986-07-01

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

  14. Hydraulic fracturing slurry transport in horizontal pipes

    SciTech Connect (OSTI)

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

    1990-09-01

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

  15. ELECTROMAGNETIC IMAGES OF THE TINTINA FAULT (NORTHERN CANADIAN CORDILLERA)

    E-Print Network [OSTI]

    Jones, Alan G.

    ELECTROMAGNETIC IMAGES OF THE TINTINA FAULT (NORTHERN CANADIAN CORDILLERA) Juanjo Ledo1 , Alan G to obtain a crustal scale electromagnetic image of the fault. A short, higher station density profile-dimensional (2- D) electromagnetic behavior of the fault. Distortion decomposition of the responses corroborated

  16. NASA Technical Memorandum 89098 The Fault-Tree Compiler

    E-Print Network [OSTI]

    Butler, Ricky W.

    L - NASA Technical Memorandum 89098 The Fault-Tree Compiler Anna L. Martensen Ricky W. Butler in preliminary design analysis. The goal of the Fault Tree Compiler (m)program is to provide the user with a tool also be performed, providing the user The motivation for the development of the Fault Tree Compiler

  17. Development of the Global Earthquake Model's neotectonic fault database

    E-Print Network [OSTI]

    New Hampshire, University of

    Development of the Global Earthquake Model's neotectonic fault database Annemarie Christophersen1 database and a unique graphical interface for the compilation of new fault data. A key design principle is that of an electronic field notebook for capturing observations a geologist would make about a fault. The database

  18. Synthesizing Round Based FaultTolerant Programs using Genetic Programming

    E-Print Network [OSTI]

    Fernandez, Thomas

    Synthesizing Round Based Fault­Tolerant Programs using Genetic Programming Ling Zhu and Sandeep based distributed fault­tolerant programs using stack based genetic pro­ gramming. Our approach evolves a fault­tolerant program based on a round based structure and the program specification. To permit

  19. Statistical estimation of multiple faults in aircraft gas turbine engines

    E-Print Network [OSTI]

    Ray, Asok

    415 Statistical estimation of multiple faults in aircraft gas turbine engines S Sarkar, C Rao of multiple faults in aircraft gas-turbine engines, based on a statistical pattern recognition tool called commercial aircraft engine. Keywords: aircraft propulsion, gas turbine engines, multiple fault estimation

  20. Online Fault Detection and Tolerance for Photovoltaic Energy Harvesting Systems

    E-Print Network [OSTI]

    Pedram, Massoud

    Online Fault Detection and Tolerance for Photovoltaic Energy Harvesting Systems Xue Lin 1 , Yanzhi, yanzhiwa, dizhu, pedram}@usc.edu, 2 naehyuck@elpl.snu.ac.kr ABSTRACT Photovoltaic energy harvesting systems, Performance, Reliability. Keywords Photovoltaic System, Fault Detection, Fault Tolerance, Photovoltaic Panel

  1. Symbolic Dynamic Analysis of Transient Time Series for Fault

    E-Print Network [OSTI]

    Ray, Asok

    Symbolic Dynamic Analysis of Transient Time Series for Fault Detection in Gas Turbine Engines paper presents a symbolic dynamics-based method for detection of incipient faults in gas turbine engines dynamics, fault detection, aircraft gas turbine engines 1 Introduction Performance monitoring of aircraft

  2. Self-potential observations during hydraulic fracturing

    SciTech Connect (OSTI)

    Moore, Jeffrey R.; Glaser, Steven D.

    2007-09-13

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

  3. An algorithm for faulted phase and feeder selection under high impedance fault conditions 

    E-Print Network [OSTI]

    Benner, Carl Lee

    1988-01-01

    . One method based on increases in third and fifth harmonic symmetrical current components under high impedance fault conditions has been proposed by Balser et. Journal model is IEEE Transactions on Power Delivery. al, of Power Technologies Inc [1...

  4. Unifying sensor fault detection with energy conservation

    E-Print Network [OSTI]

    Dobson, Simon

    Unifying sensor fault detection with energy conservation Lei Fang and Simon Dobson School energy usage. Section 2 presents our framework, which is evaluated in section 3 by means of some reliability. Sensors are often energy-hungry and cannot operate over the long term, and the data they gather

  5. Symmetrical Fault Analysis 1.0 Definition

    E-Print Network [OSTI]

    McCalley, James D.

    , shunt admittances, and -Y phase shifts are neglected. Synchronous machines (generators and motors-286]. We begin with the simplest of examples. 3.0 Example Consider a single generator supplying an R that will be faulted). Eg: steady-state internal gen voltage Xd: synchronous (steady-state) reactance IL: load

  6. All row, planar fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D; Smith, Brian Edward

    2013-07-23

    An apparatus, program product and method for detecting nodal faults may simultaneously cause designated nodes of a cell to communicate with all nodes adjacent to each of the designated nodes. Furthermore, all nodes along the axes of the designated nodes are made to communicate with their adjacent nodes, and the communications are analyzed to determine if a node or connection is faulty.

  7. Safety Requirements and Fault Trees using Retrenchment

    E-Print Network [OSTI]

    Banach, Richard

    this initial model has been created, the elicitation of safety requirements yields a fresh set of criteria are applied, the information linking the design and the safety assessment phases is often carried outSafety Requirements and Fault Trees using Retrenchment R. Banach and R. Cross Computer Science

  8. Coordinated Fault Tolerance for High-Performance Computing

    SciTech Connect (OSTI)

    Dongarra, Jack; Bosilca, George; et al.

    2013-04-08

    Our work to meet our goal of end-to-end fault tolerance has focused on two areas: (1) improving fault tolerance in various software currently available and widely used throughout the HEC domain and (2) using fault information exchange and coordination to achieve holistic, systemwide fault tolerance and understanding how to design and implement interfaces for integrating fault tolerance features for multiple layers of the software stack—from the application, math libraries, and programming language runtime to other common system software such as jobs schedulers, resource managers, and monitoring tools.

  9. Fracture-resistant lanthanide scintillators

    DOE Patents [OSTI]

    Doty, F. Patrick (Livermore, CA)

    2011-01-04

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

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

    SciTech Connect (OSTI)

    Lorenz, J.C.

    1996-01-01

    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.

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

    E-Print Network [OSTI]

    Kattenhorn, Simon

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

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

    Broader source: Energy.gov [DOE]

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

  13. 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

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

    E-Print Network [OSTI]

    Jackson, Robert B.

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

  15. Statistical RKR Modeling of Mixed-Mode Fracture

    E-Print Network [OSTI]

    Ritchie, Robert

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

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

    E-Print Network [OSTI]

    Nairn, John A.

    2009-01-01

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

  17. Faults and gravity anomalies over the East Mesa hydrothermal-geothermal system

    SciTech Connect (OSTI)

    Goldstein, N.E.; Carle, S.

    1986-05-01

    Detailed interpretations of gravity anomalies over geothermal systems may be extremely useful for mapping the fracture or fault systems that control the circulation of the thermal waters. This approach seems to be particularly applicable in areas like the Salton Trough where reactions between the thermal waters and the porous sediments produce authigenic-hydrothermal minerals in sufficient quantity to cause distinct gravity anomalies at the surface. A 3-D inversion of the residual Bouguer gravity anomaly over the East Mesa geothermal field was made to examine the densified volume of rock. We show that the data not only resolve a north-south and an intersecting northwest structure, but that it may be possible to distinguish between the active present-day hydrothermal system and an older and cooler part of the system. The densified region is compared spatially to self-potential, thermal and seismic results and we find a good concordance between the different geophysical data sets. Our results agree with previous studies that have indicated that the main feeder fault recharging the East Mesa reservoir dips steeply to the west.

  18. Study of Chelyabinsk LL5 meteorite fragment with a light lithology and its fusion crust using Mössbauer spectroscopy with a high velocity resolution

    SciTech Connect (OSTI)

    Maksimova, Alevtina A.; Petrova, Evgeniya V.; Grokhovsky, Victor I.; Oshtrakh, Michael I. Semionkin, Vladimir A.

    2014-10-27

    Study of Chelyabinsk LL5 ordinary chondrite fragment with a light lithology and its fusion crust, fallen on February 15, 2013, in Russian Federation, was carried out using Mössbauer spectroscopy with a high velocity resolution. The Mössbauer spectra of the internal matter and fusion crust were fitted and all components were related to iron-bearing phases such as olivine, pyroxene, troilite, Fe-Ni-Co alloy, and chromite in the internal matter and olivine, pyroxene, troilite, Fe-Ni-Co alloy, and magnesioferrite in the fusion crust. A comparison of the content of different phases in the internal matter and in the fusion crust of this fragment showed that ferric compounds resulted from olivine, pyroxene, and troilite combustion in the atmosphere.

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

    E-Print Network [OSTI]

    Liu, Yuwei

    2013-01-01

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

  20. 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

    2007-03-31

    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

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

    SciTech Connect (OSTI)

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

    1995-11-01

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

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

    E-Print Network [OSTI]

    Ritchie, Robert

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

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

    E-Print Network [OSTI]

    Collins, Gary S.

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

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

    E-Print Network [OSTI]

    Drummond, Tom

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

  5. 3-D description of fracture surfaces and stress-sensitivity analysis for naturally fractured reservoirs

    SciTech Connect (OSTI)

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

    1997-08-01

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

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

    E-Print Network [OSTI]

    Forbis, Robert E.

    2014-01-01

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

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

    E-Print Network [OSTI]

    Wythe, Kathy

    2013-01-01

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

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

    SciTech Connect (OSTI)

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

    2012-01-01

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

  9. Multiphase flow in fractured porous media

    SciTech Connect (OSTI)

    Firoozabadi, A.

    1995-02-01

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

  10. Anomalous transport through porous and fractured media

    E-Print Network [OSTI]

    Kang, Peter Kyungchul

    2014-01-01

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

  11. Fracture of surface cracks loaded in bending

    SciTech Connect (OSTI)

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

    1997-12-31

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

  12. Freeze fracturing of elastic porous media

    E-Print Network [OSTI]

    Vlahou, Ioanna

    2012-06-12

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

  13. Universal asymptotic umbrella for hydraulic fracture modeling

    E-Print Network [OSTI]

    Linkov, Aleksandr M

    2014-01-01

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

  14. Geomechanical review of hydraulic fracturing technology

    E-Print Network [OSTI]

    Arop, Julius Bankong

    2013-01-01

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

  15. Poroelastic response of orthotropic fractured porous media

    SciTech Connect (OSTI)

    Berryman, J.G.

    2010-12-01

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

  16. Accounting for Remaining Injected Fracturing Fluid 

    E-Print Network [OSTI]

    Zhang, Yannan

    2013-12-06

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

  17. Dynamic Fracture Toughness of Polymer Composites 

    E-Print Network [OSTI]

    Harmeet Kaur

    2012-02-14

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

  18. Undulator Hall Air Temperature Fault Scenarios

    SciTech Connect (OSTI)

    Sevilla, J.; Welch, J.; ,

    2010-11-17

    Recent experience indicates that the LCLS undulator segments must not, at any time following tuning, be allowed to change temperature by more than about {+-}2.5 C or the magnetic center will irreversibly shift outside of acceptable tolerances. This vulnerability raises a concern that under fault conditions the ambient temperature in the Undulator Hall might go outside of the safe range and potentially could require removal and retuning of all the segments. In this note we estimate changes that can be expected in the Undulator Hall air temperature for three fault scenarios: (1) System-wide power failure; (2) Heating Ventilation and Air Conditioning (HVAC) system shutdown; and (3) HVAC system temperature regulation fault. We find that for either a system-wide power failure or an HVAC system shutdown (with the technical equipment left on), the short-term temperature changes of the air would be modest due to the ability of the walls and floor to act as a heat ballast. No action would be needed to protect the undulator system in the event of a system-wide power failure. Some action to adjust the heat balance, in the case of the HVAC power failure with the equipment left on, might be desirable but is not required. On the other hand, a temperature regulation failure of the HVAC system can quickly cause large excursions in air temperature and prompt action would be required to avoid damage to the undulator system.

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

    SciTech Connect (OSTI)

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

    2008-06-30

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

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

    E-Print Network [OSTI]

    Doe, T.

    2010-01-01

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

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

    E-Print Network [OSTI]

    Doe, T.

    2010-01-01

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

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

    E-Print Network [OSTI]

    Liu, Weiqun; Li, Yushou; Wang, Bo

    2010-01-01

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

  3. Lithologic and Structural Constraints on TBM Tunneling in New York City p. 704-724 in Hutton, John D. and Rogstad, W. Dave, eds., Rapid Excavation and Tunneling Conference, 2005

    E-Print Network [OSTI]

    Merguerian, Charles

    Lithologic and Structural Constraints on TBM Tunneling in New York City p. 704-724 in Hutton, John York City (NYC), rock mass texture and mineralogy are important factors in predicting TBM penetration 11590 charlesm@dukelabs.com ABSTRACT In medium- to high-grade metamorphic terrains such as found in New

  4. Development of Integrated Meso/Microscale Traffic Simulation Software for Testing Fault Detection and Handling in AHS

    E-Print Network [OSTI]

    Horowitz, Roberto

    2004-01-01

    Traffic Simulation Software for Testing Fault Detection andTraf?c Simulation Software for Testing Fault Detection andTraf?c Simulation Software for Testing Fault Detection and

  5. Features and Dimensions of the Hayward fault zone in the Strawberry and Blackberry Creek Area Berkeley, California

    E-Print Network [OSTI]

    Williams, P.L.

    2011-01-01

    Hayward Fault Zone in the Strawberry and Blackberry Creekward Fault Zone in the Strawberry and Blackberry Creek Area,Hayward fault zone in the Strawberry and Blackberry Creek

  6. Similarity Matching Techniques for Fault Diagnosis in Automotive Infotainment Electronics

    E-Print Network [OSTI]

    Kabir, Mashud

    2009-01-01

    Fault diagnosis has become a very important area of research during the last decade due to the advancement of mechanical and electrical systems in industries. The automobile is a crucial field where fault diagnosis is given a special attention. Due to the increasing complexity and newly added features in vehicles, a comprehensive study has to be performed in order to achieve an appropriate diagnosis model. A diagnosis system is capable of identifying the faults of a system by investigating the observable effects (or symptoms). The system categorizes the fault into a diagnosis class and identifies a probable cause based on the supplied fault symptoms. Fault categorization and identification are done using similarity matching techniques. The development of diagnosis classes is done by making use of previous experience, knowledge or information within an application area. The necessary information used may come from several sources of knowledge, such as from system analysis. In this paper similarity matching tec...

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

    E-Print Network [OSTI]

    Christian Ligoure; Serge Mora

    2013-01-15

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

  8. Fault-induced delayed voltage recovery in a long inhomogeneous...

    Office of Scientific and Technical Information (OSTI)

    Article: Fault-induced delayed voltage recovery in a long inhomogeneous power-distribution feeder Citation Details In-Document Search This content will become publicly...

  9. Fault Tolerant Evaluation of Continuous Selection Queries over Sensor Data

    E-Print Network [OSTI]

    Lazaridis, Iosif; Han, Qi; Mehrotra, Sharad; Venkatasubramanian, Nalini

    2009-01-01

    Evaluation of Continuous Selection Queries over Sensor Dataevaluation of continuous selection queries (CSQs) over sensor-sensor suffices and there is no Fault Tolerant Evaluation of

  10. STRESS AND FAULTING IN THE COSO GEOTHERMAL FIELD: UPDATE AND...

    Open Energy Info (EERE)

    108 24 in a transitional strike-slip to normal faulting stress regime. These structures bound regions of intense micro-seismicity and are complexly associated with surface...

  11. Dating of major normal fault systems using thermochronology-...

    Open Energy Info (EERE)

    faults, timing of ductile mylonite formation and passage of rocks through the crystal-plastic to brittle transition, and multiple events of extensional unroofing. Here we...

  12. Post-Cretaceous faulting at head of Mississippi embayment

    SciTech Connect (OSTI)

    Nelson, W.J. (Illinois State Geological Survey, Champaign, IL (United States)); Harrison, R.W. (Geological Survey, Reston, VA (United States))

    1993-03-01

    Recent mapping in southernmost Illinois and southeastern Missouri has revealed numerous faults that displace Cretaceous and Tertiary strata. Units as young as the Pliocene-Pleistocene( ) Mounds Gravel are deformed; some faults possibly displace Quaternary sediments. The faults strike northeast, dip nearly vertically, and exhibit characteristics of dextral strike-slip. Pull-apart grabens occur along right-stepping fault strands, they contain chaotically jumbled blocks of Paleozoic, Cretaceous and Tertiary rocks downdropped as much as 800 m relative to wall rocks. Faults at the head of the Mississippi embayment probably originated during Cambrian rifting (Reelfoot rift) and have a long, complex history of reactivation under different stress fields. Some faults are on strike with faults in the New Madrid seismic zone. Kinematics of post-Cretaceous displacements fit the contemporary stress regime of ENE-WSW compression. Similar fault orientations and kinematics, as well as close proximity, suggest a close link between faulting at the head of the embayment and ongoing tectonism in the New Madrid seismic zone.

  13. MODELING AND SIMULATION OF HVAC FAULTS IN ENERGYPLUS

    E-Print Network [OSTI]

    Basarkar, Mangesh

    2013-01-01

    and simulated building energy performance, Norford et al. (faults on whole building performance – energy consumption,and simulated energy performance of buildings is that most

  14. Recency of Faulting and Neotectonic Framework in the Dixie Valley...

    Open Energy Info (EERE)

    by active geothermal springs. More specifically, our investigation shows that induced stress concentrations at the endpoints of normal fault ruptures appear to promote favorable...

  15. Recency Of Faulting And Neotechtonic Framework In The Dixie Valley...

    Open Energy Info (EERE)

    by active geothermal springs. More specifically, our investigation shows that induced stress concentrations at the endpoints of normal fault ruptures appear to promote favorable...

  16. Active Fault Controls At High-Temperature Geothermal Sites- Prospectin...

    Open Energy Info (EERE)

    the level of unrecognized active faults present in these areas. Analysis of low-sun-angle aerial photography acquired over the Needle Rocks, Astor Pass, Empire, and Lee...

  17. Fault-tolerant distributed transactions for partitioned OLTP databases

    E-Print Network [OSTI]

    Jones, Evan P. C. (Evan Philip Charles), 1981-

    2012-01-01

    This thesis presents Dtxn, a fault-tolerant distributed transaction system designed specifically for building online transaction processing (OLTP) databases. Databases have traditionally been designed as general purpose ...

  18. Arc-Fault Detector Algorithm Evaluation Method Utilizing Prerecorded...

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

    Electrical Code Article 690.11 requires photovoltaic systems on or penetrating a building to include a DC arc-fault protection device. In order to satisfy this...

  19. Checksum-Based Fault Tolerance for LU Factorization

    E-Print Network [OSTI]

    Davies, Teresa

    2014-01-01

    study of failures in high-performance computing systems. InFault tolerant high performance computing by a codingfor large-scale high- performance computing. In 2012

  20. Effects of Volcanism, Crustal Thickness, and Large Scale Faulting...

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

    Effects of Volcanism, Crustal Thickness, and Large Scale Faulting on the Development and Evolution of Geothermal Systems: Collaborative Project in Chile Effects of Volcanism,...

  1. MICRO-SEISMICITY, FAULT STRUCTURE AND HYDRAULIC COMPARTMENTALIZATION...

    Open Energy Info (EERE)

    LibraryAdd to library Conference Proceedings: MICRO-SEISMICITY, FAULT STRUCTURE AND HYDRAULIC COMPARTMENTALIZATION WITHIN THE COSO GETHERMAL FIELD, CALIFORNIA Abstract High...

  2. PV Arc Fault Detector Challenges Due to Module Frequency Response...

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

    This poster does not contain any proprietary or confidential information. Introduction PV system arc faults have led to a number of rooftop fires which have caused significant...

  3. A Comparison of Fault Detection Methods For a Transcritical Refrigeration System 

    E-Print Network [OSTI]

    Janecke, Alex Karl

    2012-10-19

    pairings of four faults: over/undercharge, evaporator fouling, gas cooler fouling, and compressor valve leakage. This technique allows for low cost measurement and independent detection of individual faults even when multiple faults are present. Results...

  4. Neural Network-Based Classification of Single-Phase Distribution Transformer Fault Data 

    E-Print Network [OSTI]

    Zhang, Xujia

    2006-08-16

    The ultimate goal of this research is to develop an online, non-destructive, incipient fault detection system that is able to detect incipient faults in transformers and other electric equipment before the faults become ...

  5. Evaluation of a Decoupling-Based Fault Detection and Diagnostic Technique - Part I: Field Emulation Evaluation 

    E-Print Network [OSTI]

    Li, H.; Braun, J.

    2006-01-01

    Existing methods addressing automated fault detection and diagnosis (FDD) for vapor compression air conditioning system have good performance for faults that occur individually, but they have difficulty in handling multiple-simultaneous faults...

  6. ALLIANCE: An Architecture for Fault Tolerant, Cooperative Control of Heterogeneous Mobile Robots

    E-Print Network [OSTI]

    Parker, Lynne E.

    ALLIANCE: An Architecture for Fault Tolerant, Cooperative Control of Heterogeneous Mobile Robots ALLIANCE, that utilizes adaptive action selection to achieve fault toler- ant cooperative control in robot demonstration. These experiments illustrate the ability of ALLIANCE to achieve adaptive, fault

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

    E-Print Network [OSTI]

    Oeth, Cassandra V

    2013-11-25

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

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

    E-Print Network [OSTI]

    Deng, Jiayao

    2011-02-22

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

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

    E-Print Network [OSTI]

    Najmuddin, Ilyas Juzer

    2004-09-30

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

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

    E-Print Network [OSTI]

    Rodriguez, Erika

    2005-11-01

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

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Fang, Xinding

    2011-01-01

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

  13. Nonmonotonic fracture behavior of polymer nanocomposites

    E-Print Network [OSTI]

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

    2015-06-02

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

  14. Hydrothermal coupling in a rough fracture

    E-Print Network [OSTI]

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

    2006-01-01

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

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

    SciTech Connect (OSTI)

    Jetzabeth Ramirez-Sabag; Fernando Samaniego V.

    1992-01-01

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

  16. Simulation on Discrete Fracture Network Using Flexible Voronoi Gridding 

    E-Print Network [OSTI]

    Syihab, Zuher

    2011-02-22

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

  17. 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.

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

    E-Print Network [OSTI]

    Alampi, Ann M

    2014-01-01

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

  19. Numerical Modeling of Hydraulic Fracturing in Oil Sands

    E-Print Network [OSTI]

    2008-11-16

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

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

    E-Print Network [OSTI]

    Densirimongkol, Jurairat

    2010-10-12

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

  1. Selection of fracture fluid for stimulating tight gas reservoirs 

    E-Print Network [OSTI]

    Malpani, Rajgopal Vijaykumar

    2007-04-25

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

  2. Acid Fracturing Feasibility Study for Heterogeneous Carbonate Formation 

    E-Print Network [OSTI]

    Suleimenova, Assiya

    2015-03-03

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

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

    E-Print Network [OSTI]

    Nino Penaloza, Andrea

    2013-05-01

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

  4. Fracture characterization from seismic measurements in a borehole

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    2015-01-01

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

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

    E-Print Network [OSTI]

    Poliannikov, Oleg V.

    2011-01-01

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

  6. Numerical modeling of hydraulic fracture initiation and development

    E-Print Network [OSTI]

    2007-05-25

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

  7. On equivalence of thinning fluids used for hydraulic fracturing

    E-Print Network [OSTI]

    Linkov, Alexander

    2012-01-01

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

  8. Hydraulic Fracture Monitoring: A Jonah Field Case Study

    E-Print Network [OSTI]

    Seher, T.

    2011-01-01

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

  9. Fracture Characterization from Scattered Energy: A Case Study

    E-Print Network [OSTI]

    Grandi, Samantha K.

    2006-01-01

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

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

    E-Print Network [OSTI]

    Al Harbi, Mishal H.

    2005-08-29

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

  11. Geomechanical Development of Fractured Reservoirs During Gas Production 

    E-Print Network [OSTI]

    Huang, Jian

    2013-04-05

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

  12. 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 ...

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

    E-Print Network [OSTI]

    Zamanian, S. Ahmad

    2012-01-01

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

  14. 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 ...

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

    E-Print Network [OSTI]

    Chi, Shihong

    2006-01-01

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

  16. Effects of subsurface fracture interactions on surface deformation

    E-Print Network [OSTI]

    Jerry, Ruel (Ruel Valentine)

    2013-01-01

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

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

    SciTech Connect (OSTI)

    Huang, Hai; Plummer, Mitchell; Podgorney, Robert

    2013-02-01

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

  18. Compartmentalization analysis using discrete fracture network models

    SciTech Connect (OSTI)

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

    1997-08-01

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

  19. Fracture Toughness Prediction for MWCNT Reinforced Ceramics

    SciTech Connect (OSTI)

    Henager, Charles H.; Nguyen, Ba Nghiep

    2013-09-01

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

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

    SciTech Connect (OSTI)

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

    2005-06-15

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

  1. Fault Tolerant Arithmetic with Applications in Nanotechnology based Systems

    E-Print Network [OSTI]

    Rao, Wenjing

    Fault Tolerant Arithmetic with Applications in Nanotechnology based Systems Wenjing Rao UC San nanotechnologies have been displaying the Neg- ative Differential Resistance (NDR) characteristic, which makes them fault-tolerant arithmetic in NDR nanotechnologies. Specifically, we show how linear block codes can

  2. Automatic Fault Characterization via Abnormality-Enhanced Classification

    SciTech Connect (OSTI)

    Bronevetsky, G; Laguna, I; de Supinski, B R

    2010-12-20

    Enterprise and high-performance computing systems are growing extremely large and complex, employing hundreds to hundreds of thousands of processors and software/hardware stacks built by many people across many organizations. As the growing scale of these machines increases the frequency of faults, system complexity makes these faults difficult to detect and to diagnose. Current system management techniques, which focus primarily on efficient data access and query mechanisms, require system administrators to examine the behavior of various system services manually. Growing system complexity is making this manual process unmanageable: administrators require more effective management tools that can detect faults and help to identify their root causes. System administrators need timely notification when a fault is manifested that includes the type of fault, the time period in which it occurred and the processor on which it originated. Statistical modeling approaches can accurately characterize system behavior. However, the complex effects of system faults make these tools difficult to apply effectively. This paper investigates the application of classification and clustering algorithms to fault detection and characterization. We show experimentally that naively applying these methods achieves poor accuracy. Further, we design novel techniques that combine classification algorithms with information on the abnormality of application behavior to improve detection and characterization accuracy. Our experiments demonstrate that these techniques can detect and characterize faults with 65% accuracy, compared to just 5% accuracy for naive approaches.

  3. Fault current limiter with shield and adjacent cores

    DOE Patents [OSTI]

    Darmann, Francis Anthony; Moriconi, Franco; Hodge, Eoin Patrick

    2013-10-22

    In a fault current limiter (FCL) of a saturated core type having at least one coil wound around a high permeability material, a method of suppressing the time derivative of the fault current at the zero current point includes the following step: utilizing an electromagnetic screen or shield around the AC coil to suppress the time derivative current levels during zero current conditions.

  4. An Information Flow Model of Fault Detection Margaret C. Thompson ?

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    not be practical. Nonethe­ less, Relay provides insight into testing and fault de­ tection and suggests an approach and Computer Science Amherst, MA 01003 University of California Irvine, CA 92717 Abstract Relay is a model of how a fault causes a failure on execution of some test datum. This process begins with introduction

  5. Fault Tolerant Oxygen Control of a Diesel Engine Air System

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Fault Tolerant Oxygen Control of a Diesel Engine Air System Rainer Nitsche Matthias Bitzer control problem of a Diesel engine air system having a jammed Exhaust Gas Recirculation (EGR) valve of the air system. Keywords: Fault tolerant control, Diesel engine, Air system, Model-based trajectory

  6. Symbolic identification for fault detection in aircraft gas turbine engines

    E-Print Network [OSTI]

    Ray, Asok

    Symbolic identification for fault detection in aircraft gas turbine engines S Chakraborty, S Sarkar and computationally inexpensive technique of component-level fault detection in aircraft gas-turbine engines identification, gas turbine engines, language-theoretic analysis 1 INTRODUCTION The propulsion system of modern

  7. On Distributed Fault-Tolerant Detection in Wireless Sensor Networks

    E-Print Network [OSTI]

    Dong, Ming

    --Distributed event detection, fault tolerance, sensor fusion, energy-efficiency, wireless sensor networks. æ 1 to choose a proper neighborhood size n for a sensor node in fault correction such that the energy could to achieve better detection and better balance between detection accuracy and energy usage. Our work makes

  8. Common Trends in Software Fault and Failure Data

    E-Print Network [OSTI]

    Goseva-Popstojanova, Katerina

    Common Trends in Software Fault and Failure Data Maggie Hamill, Member, IEEE, and Katerina Goseva with the findings from related studies. The consistency of several main trends across software systems in this paper-Popstojanova, Senior Member, IEEE Abstract--The benefits of the analysis of software faults and failures have been

  9. Fault Reporting Processes in Business-Critical Systems

    E-Print Network [OSTI]

    and reporting7 Quantitative and qualitativeHazard analysis vs. fault report analysis - DAIM 6 Qualitative projects4 Quantitative, explorativeFault report study of four projects3 Qualitative, descriptive and Information Science (IDI) University of Science and Technology (NTNU) Trondheim, Norway PhD thesis

  10. Fault Detection and Diagnosis Method for VAV Terminal Units 

    E-Print Network [OSTI]

    Miyata, M.; Yoshida, H.; Asada, M.; Wang, F.; Hashiguchi, S.

    2004-01-01

    This paper proposes two fault detection and diagnosis methods for VAV units without a sensor of supply air volume, and the results of applying these methods to a real building are presented. One method detects faults by applying a statistical method...

  11. SHIELD: A Fault-Tolerant MPI for an Infiniband Cluster

    E-Print Network [OSTI]

    Yeom, Heon Young

    SHIELD: A Fault-Tolerant MPI for an Infiniband Cluster Hyuck Han, Hyungsoo Jung, Jai Wug Kim, a successful solution has yet to be delivered to commercial vendors. This paper presents SHIELD, a prac- tical and easily-deployable fault-tolerant MPI and management system of MPI for an Infiniband cluster. SHIELD

  12. Outlier Detection Rules for Fault Detection in Solar Photovoltaic Arrays

    E-Print Network [OSTI]

    Lehman, Brad

    . The models must be modified due to different PV capacity, solar cell technology, or installation locationOutlier Detection Rules for Fault Detection in Solar Photovoltaic Arrays Ye Zhao, Brad Lehman Abstract-- Solar photovoltaic (PV) arrays are unique power sources that may have uncleared fault current

  13. Original Article Multi-sensor information fusion for fault

    E-Print Network [OSTI]

    Ray, Asok

    The article addresses data-driven fault detection in commercial aircraft gas turbine engines in the framework is validated on the NASA C-MAPSS simulation test bed of aircraft gas turbine engines; both single is also addressed. Keywords Gas turbine engines, fault detection, information fusion Date received: 15 May

  14. Fault Detection, Identification and Accommodation for an Electro-hydraulic

    E-Print Network [OSTI]

    Yao, Bin

    in electro-hydraulic systems. It is well known fact that any realistic model of a hydraulic system suffersFault Detection, Identification and Accommodation for an Electro-hydraulic System: An Adaptive, such a scheme becomes a natural choice for designing robust fault detection algorithms for electro-hydraulic

  15. Multi-sensor Wireless System for Fault Detection in Induction Motors

    E-Print Network [OSTI]

    Tarkesh Esfahani, Ehsan

    2012-01-01

    2 Faults in Motors 2.1 Bearing Faultcombined faults in induction motors,” IEEE Transactions onV. Climente-Alarcon, “Induction motor diagnosis based on a

  16. Development of Integrated Meso/Microscale Traffic Simulation Software for Testing Fault Detection and Handling Algorithms in AHS: Final Report

    E-Print Network [OSTI]

    Horowitz, Roberto

    2003-01-01

    Traffic Simulation Software for Testing Fault Detection andTra?c Simulation Software for Testing Fault Detection and

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

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

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

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

    E-Print Network [OSTI]

    A. Bakulin, V. Grechka, I. Tsvankin

    2000-11-02

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

  19. Experimental and Analytical Research on Fracture Processes in ROck

    SciTech Connect (OSTI)

    Herbert H.. Einstein; Jay Miller; Bruno Silva

    2009-02-27

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

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

    E-Print Network [OSTI]

    Ze'ev, Reches

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

  1. Application-Specific Fault Tolerance via Data Access Characterization

    SciTech Connect (OSTI)

    Ali, Nawab; Krishnamoorthy, Sriram; Govind, Niranjan; Kowalski, Karol; Sadayappan, Ponnuswamy

    2011-08-30

    Recent trends in semiconductor technology and supercomputer design predict an increasing probability of faults during an application's execution. Designing an application that is resilient to system failures requires careful evaluation of the impact of various approaches on preserving key application state. In this paper, we present our experiences in an ongoing effort to make a large computational chemistry application fault tolerant. We construct the data access signatures of key application modules to evaluate alternative fault tolerance approaches. We present the instrumentation methodology, characterization of the application modules, and evaluation of fault tolerance techniques using the information collected. The application signatures developed capture application characteristics not traditionally revealed by performance tools. We believe these can be used in the design and evaluation of runtimes beyond fault tolerance.

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

    E-Print Network [OSTI]

    Wang, Wenxin

    2006-04-12

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

  3. 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

  4. The Transport of Nuclear Contamination in Fractured Porous Media

    E-Print Network [OSTI]

    Douglas Jr., Jim

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

  5. 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

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

    E-Print Network [OSTI]

    Zhang, Junjing

    2014-07-10

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

  7. 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

  8. 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

  9. 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

  10. 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

  11. Poroelastic modeling of seismic boundary conditions across a fracture

    E-Print Network [OSTI]

    2007-07-20

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

  12. Automatic Fracture Reduction Thomas Albrecht and Thomas Vetter

    E-Print Network [OSTI]

    Vetter, Thomas

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

  13. 6. Fracture mechanics lead author: J, R. Rice

    E-Print Network [OSTI]

    6. Fracture mechanics lead author: J, R. Rice Division of Applied Sciences, Harvard University. F. Shih, and the ASME/AMD Technical Committee on Fracture Mechanics, pro- vided by A. S. Argon, S. N, W. D. Stuart, and R. Thomson. 6.0 ABSTRACT Fracture mechanics is an active research field

  14. THE EFFECT OF SURFACE TENSION IN MODELING INTERFACIAL FRACTURE

    E-Print Network [OSTI]

    THE EFFECT OF SURFACE TENSION IN MODELING INTERFACIAL FRACTURE By Tsvetanka Sendova and Jay R Fracture Tsvetanka Sendova and Jay R. Walton Institute for Mathematics and Its Applications, University@math.tamu.edu Abstract. In this article the problem of an interface fracture between two isotropic linear elas- tic

  15. Fibre Based Modeling of Wood Dynamics and Fracture

    E-Print Network [OSTI]

    Bridson, Robert

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

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

    E-Print Network [OSTI]

    Toussaint, Renaud

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

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

    E-Print Network [OSTI]

    Ritchie, Robert

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

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

    E-Print Network [OSTI]

    Nairn, John A.

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

  19. Introduction Fracture at small length scales is a concern

    E-Print Network [OSTI]

    Suo, Zhigang

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

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

    E-Print Network [OSTI]

    Volinsky, Alex A.

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

  1. Meshfree Simulations of Spall Fracture By Bo Ren ,

    E-Print Network [OSTI]

    Li, Shaofan

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

  2. Molecular dynamics study of fracture accompanied by chemical reaction

    E-Print Network [OSTI]

    Krivtsov, Anton M.

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

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

    E-Print Network [OSTI]

    Krivtsov, Anton M.

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

  4. Short communication Fractal in fracture of bulk metallic glass

    E-Print Network [OSTI]

    Gao, Jianbo

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

  5. A dimensional decomposition method for stochastic fracture mechanics

    E-Print Network [OSTI]

    Rahman, Sharif

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

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

    E-Print Network [OSTI]

    Cirak, Fehmi

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

  7. RESIDUAL STRESS EFFECTS IN FRACTURE OF COMPOSITES AND ADHESIVES

    E-Print Network [OSTI]

    Nairn, John A.

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

  8. A unified enrichment scheme for fracture Safdar Abbas

    E-Print Network [OSTI]

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

  9. Finite Element Model of Fracture Formation on Growing Surfaces

    E-Print Network [OSTI]

    Prusinkiewicz, Przemyslaw

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

  10. Analyzing and Simulating Fracture Patterns of Theran Wall Paintings

    E-Print Network [OSTI]

    Singh, Jaswinder Pal

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

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

    E-Print Network [OSTI]

    Barr, Al

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

  12. Feb. 11, 2008 Advanced Fault Tolerance Solutions for High Performance Computing 1/47 Advanced Fault Tolerance Solutions

    E-Print Network [OSTI]

    Engelmann, Christian

    Feb. 11, 2008 Advanced Fault Tolerance Solutions for High Performance Computing 1/47 RAS RAS Advanced Fault Tolerance Solutions for High Performance Computing Christian Engelmann Oak Ridge National Solutions for High Performance Computing 2/47 · Nation's largest energy laboratory · Nation's largest

  13. Rupture Dynamics of Strike-Slip Faults with Stepovers: From Conceptually Simplified to Realistically Complex Fault Systems 

    E-Print Network [OSTI]

    Liu, Zaifeng

    2014-05-05

    . The coupling effect of those two effects has also been studied. The possible correlation between the slip gradient nearby the first fault end and the ability of the rupture to jump over the structure stepover in the strike-slip fault system has been verified...

  14. A Global Model for Fracture Falloff Analysis 

    E-Print Network [OSTI]

    Marongiu-Porcu, Matteo

    2014-10-29

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

  15. Gas condensate damage in hydraulically fractured wells 

    E-Print Network [OSTI]

    Adeyeye, Adedeji Ayoola

    2004-09-30

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

  16. Correlating toughness and roughness in ductile fracture

    E-Print Network [OSTI]

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

    2013-07-16

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

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

    E-Print Network [OSTI]

    Peirce, Anthony

    of Bunger et al. (In Press) is consistent with past observations of multiple hydraulic fracture growth from Simultaneous Growth of Multiple Hydraulic Fractures A.P. Peirce, University of British Columbia and A.P. Bunger in horizontal well stimulation is the generation of hydraulic fractures (HFs) from all perforation clusters

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

    E-Print Network [OSTI]

    Peirce, Anthony

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

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

    E-Print Network [OSTI]

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

  20. Lithologically Controlled | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma, Arizona:Oregon: Energy ResourcesGrove, Iowa:Lisle,Trough LLC

  1. Locating hardware faults in a parallel computer

    DOE Patents [OSTI]

    Archer, Charles J.; Megerian, Mark G.; Ratterman, Joseph D.; Smith, Brian E.

    2010-04-13

    Locating hardware faults in a parallel computer, including defining within a tree network of the parallel computer two or more sets of non-overlapping test levels of compute nodes of the network that together include all the data communications links of the network, each non-overlapping test level comprising two or more adjacent tiers of the tree; defining test cells within each non-overlapping test level, each test cell comprising a subtree of the tree including a subtree root compute node and all descendant compute nodes of the subtree root compute node within a non-overlapping test level; performing, separately on each set of non-overlapping test levels, an uplink test on all test cells in a set of non-overlapping test levels; and performing, separately from the uplink tests and separately on each set of non-overlapping test levels, a downlink test on all test cells in a set of non-overlapping test levels.

  2. Self field triggered superconducting fault current limiter

    DOE Patents [OSTI]

    Tekletsadik, Kasegn D. (Rexford, NY)

    2008-02-19

    A superconducting fault current limiter array with a plurality of superconductor elements arranged in a meanding array having an even number of supconductors parallel to each other and arranged in a plane that is parallel to an odd number of the plurality of superconductors, where the odd number of supconductors are parallel to each other and arranged in a plane that is parallel to the even number of the plurality of superconductors, when viewed from a top view. The even number of superconductors are coupled at the upper end to the upper end of the odd number of superconductors. A plurality of lower shunt coils each coupled to the lower end of each of the even number of superconductors and a plurality of upper shunt coils each coupled to the upper end of each of the odd number of superconductors so as to generate a generally orthoganal uniform magnetic field during quenching using only the magenetic field generated by the superconductors.

  3. Online Monitoring System for Performance Fault Detection

    SciTech Connect (OSTI)

    Gioiosa, Roberto; Kestor, Gokcen; Kerbyson, Darren J.

    2014-05-19

    To achieve the exaFLOPS performance within a contain power budget, next supercomputers will feature hundreds of millions of components operating at low- and near-threshold voltage. As the probability that at least one of these components fails during the execution of an application approaches certainty, it seems unrealistic to expect that any run of a scientific application will not experience some performance faults. We believe that there is need of a new generation of light-weight performance and debugging tools that can be used online even during production runs of parallel applications and that can identify performance anomalies during the application execution. In this work we propose the design and implementation of a monitoring system that continuously inspects the evolution of run

  4. Numerical simulation of the environmental impact of hydraulic fracturing of tight/shale gas reservoirs on near-surface groundwater: Background, base cases, shallow reservoirs, short-term gas, and water transport: Simulation of Impact of Hydraulic Fracturing on Groundwater

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

    Reagan, Matthew T.; Moridis, George J.; Keen, Noel D.; Johnson, Jeffrey N.

    2015-04-18

    Hydrocarbon production from unconventional resources and the use of reservoir stimulation techniques, such as hydraulic fracturing, has grown explosively over the last decade. However, concerns have arisen that reservoir stimulation creates significant environmental threats through the creation of permeable pathways connecting the stimulated reservoir with shallower freshwater aquifers, thus resulting in the contamination of potable groundwater by escaping hydrocarbons or other reservoir fluids. This study investigates, by numerical simulation, gas and water transport between a shallow tight-gas reservoir and a shallower overlying freshwater aquifer following hydraulic fracturing operations, if such a connecting pathway has been created. We focus on twomore »general failure scenarios: (1) communication between the reservoir and aquifer via a connecting fracture or fault and (2) communication via a deteriorated, preexisting nearby well. We conclude that the key factors driving short-term transport of gas include high permeability for the connecting pathway and the overall volume of the connecting feature. Production from the reservoir is likely to mitigate release through reduction of available free gas and lowering of reservoir pressure, and not producing may increase the potential for release. We also find that hydrostatic tight-gas reservoirs are unlikely to act as a continuing source of migrating gas, as gas contained within the newly formed hydraulic fracture is the primary source for potential contamination. Such incidents of gas escape are likely to be limited in duration and scope for hydrostatic reservoirs. Reliable field and laboratory data must be acquired to constrain the factors and determine the likelihood of these outcomes.« less

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

    E-Print Network [OSTI]

    Sotelo Gamboa, Edith

    2014-11-12

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

  6. Visualization of stacking faults in fcc crystals in plastic deformations

    E-Print Network [OSTI]

    Takeshi Kawasaki; Akira Onuki

    2011-11-27

    Using molecular dynamics simulation, we investigate the dynamics of stacking faults in fcc crystals in uniaxial stretching in a Lennard-Jones binary mixture composed of 4096 particles in three dimensions. We visualize stacking faults using a disorder variable $D_j(t)$ for each particle $j$ constructed from local bond order parameters based on spherical harmonics (Steinhardt order parameters). Also introducing a method of bond breakage, we examine how stacking faults are formed and removed by collective particle motions. These processes are relevant in plasticity of fcc crystals.

  7. Static Fault Attack on Hardware DES Registers Philippe Loubet-Moundi, Francis Olivier, and David Vigilant

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    Static Fault Attack on Hardware DES Registers Philippe Loubet-Moundi, Francis Olivier, and David deals with static faults which lie in between. A static fault modifies a value loaded in a volatile], quickly became a privileged target for DFA. #12;2 Static Fault Attacks on Hardware DES Registers Indeed

  8. Can Fault Prediction Models and Metrics be Used for Vulnerability Prediction? Yonghee Shin and Laurie Williams

    E-Print Network [OSTI]

    Young, R. Michael

    are built with traditional metrics of complexity, code churn, and fault history. We have performed to the code [17]. Hence, complexity metrics and code churn metrics have been used for fault prediction [5, 17 fault prediction metrics ­ complexity, code churn, and fault history metrics for vulnerability

  9. Seismic behaviour of the Dead Sea fault along Araba valley, Y. Klinger,1,

    E-Print Network [OSTI]

    Avouac, Jean-Philippe

    rue Lafayette, F-75480 Paris cedex 10, France 4 Department of Geology, University of Jordan, Amman-lateral strike-slip fault. South of the Dead Sea basin, the Wadi Araba fault extends over 160 km to the Gulf the fault except around the Dead Sea and Gulf of Aqaba, where the fault splays into complex pull-apart basin

  10. EERE PowerPoint 97-2004 Template: Green Version

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

    Lithology: Lithologic diversity produces rheological contrasts which can enhance fracturing and fluid flow, and relatively young rocks have had fewer opportunities for...

  11. Molecular basis of fracture in polystyrene films

    SciTech Connect (OSTI)

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

    1993-12-31

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

  12. Correlating toughness and roughness in ductile fracture

    E-Print Network [OSTI]

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

    2013-01-01

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

  13. Fracture simulation for zirconia toughened alumina microstructure

    E-Print Network [OSTI]

    Kim, Kyungmok; Forest, Bernard

    2013-01-01

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

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

    SciTech Connect (OSTI)

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

    1991-03-01

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

  15. Volumetric Curvature and Coherency Assisted Fault Mapping and Fracture Prediction of Carbonate Reservoir Huabei Field, North China 

    E-Print Network [OSTI]

    Li, Allen

    2014-08-10

    Seismic attribute analysis in recent decades has been an instrumental tool in improving the quality of reservoir characterization for hydrocarbon identification. Coherency and curvature are geometric seismic attributes which measure seismic...

  16. An information model for inter-organizational fault Patricia Marcu

    E-Print Network [OSTI]

    in the IT Infrastructure Library (ITIL) [2] and related frameworks in the area of IT service management (ITSM). But since ITIL and the related ITSM frameworks do not consider specific aspects of inter- organizational (fault

  17. Controls on Fault-Hosted Fluid Flow: Preliminary Results from...

    Open Energy Info (EERE)

    Controls on Fault-Hosted Fluid Flow: Preliminary Results from the Coso Geothermal Field, CA Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference...

  18. Robust model-based fault diagnosis for chemical process systems 

    E-Print Network [OSTI]

    Rajaraman, Srinivasan

    2006-08-16

    Fault detection and diagnosis have gained central importance in the chemical process industries over the past decade. This is due to several reasons, one of them being that copious amount of data is available from a large ...

  19. Thermal Waters Along The Konocti Bay Fault Zone, Lake County...

    Open Energy Info (EERE)

    Thermal Waters Along The Konocti Bay Fault Zone, Lake County, California- A Re-Evaluation Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article:...

  20. Microgrid Fault Protection Based on Symmetrical and Differential Current Components

    E-Print Network [OSTI]

    Microgrid Fault Protection Based on Symmetrical and Differential Current Components Prepared.........................................................................................8 2. AEP CERTS MICROGRID .........................................................................9 ........................................................................67 #12;3 Index of Figures Figure 1: Schematic representation of the AEP CERTS microgrid

  1. Compatible and Cost-Effective Fault Diagnostic Solutions for...

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

    Compatible and Cost-Effective Fault Diagnostic Solutions for Air Handling Unit-Variable Air Volume and Air Handling Unit-Constant Air Volume Systems - 2014 BTO Peer Review...

  2. COMPLETE FAULT ANALYSIS FOR LONG TRANSMISSION LINE USING

    E-Print Network [OSTI]

    sys- tem based approach is described in (Girgis and Johns, 1996) and a phasor measurement unit (PMU Measurement Unit (PMU) are further developed. Previous efforts were aimed at implementing accu- rate fault

  3. Fault Mechanics Earth Structure (2nd Edition), 2004

    E-Print Network [OSTI]

    , and normal faulting is ratio of pore-fluid pressure and lithostatic pressure ( ranges from 0.4 for hydrostatic fluid pressure to 1 for lithostatic fluid pressure) © EarthStructure (2nd ed) 610/25/2010 #12

  4. MODELING AND SIMULATION OF HVAC FAULTS IN ENERGYPLUS

    E-Print Network [OSTI]

    Basarkar, Mangesh

    2013-01-01

    http://www.eia.doe.gov/emeu/cbecs/ EnergyPlus. 2011, http://of HVAC Results in EnergyPlus Mangesh Basarkar, XiufengOF HVAC FAULTS IN ENERGYPLUS Mangesh Basarkar, Xiufeng Pang,

  5. A Low Overhead Fault Tolerant Coherence Protocol for CMP Architectures

    E-Print Network [OSTI]

    Acacio, Manuel

    A Low Overhead Fault Tolerant Coherence Protocol for CMP Architectures Ricardo Fern Murcia SPAIN {r.fernandez,jmgarcia,meacacio}@ditec.um.es Jos´e Duato Dpto. Inform´atica de Sistemas y

  6. Recent earthquake sequences at Coso: Evidence for conjugate faulting...

    Open Energy Info (EERE)

    Recent earthquake sequences at Coso: Evidence for conjugate faulting and stress loading near a geothermal field Jump to: navigation, search OpenEI Reference LibraryAdd to library...

  7. Understanding Fault Characteristics And Sediment Depth For Geothermal...

    Open Energy Info (EERE)

    of primarily E-W directed extension along N-NNW striking normal faults. Water well drilling on the eastern slopes of the Wassuk Range, west of the city of Hawthorne, Nevada...

  8. Fault Block Kinematics at a Releasing Stepover of the Eastern...

    Open Energy Info (EERE)

    Nascent Metamorphic Core Complex Citation Christopher J. Pluhar,Robert S. Coe,Jonathan C. Lewis,Francis C. Monastero,Jonathan M.G. Glen. 2006. Fault Block Kinematics at a Releasing...

  9. Non-intrusive fault detection in reciprocating compressors

    E-Print Network [OSTI]

    Schantz, Christopher James

    2011-01-01

    This thesis presents a set of techniques for non-intrusive sensing and fault detection in reciprocating compressors driven by induction motors. The procedures developed here are "non-intrusive" because they rely only on ...

  10. Fusing strategies for the dual-voltage fault

    E-Print Network [OSTI]

    Shrivastava, Rupam, 1981-

    2005-01-01

    This thesis focuses on the 42V - 14V fault in a dual voltage system and discusses the possibility of effective fusing. A simple model for the system had been created from technical documentation. Based on the model and the ...

  11. Fracture of Thermosetting Polymers: Experiments and Modeling 

    E-Print Network [OSTI]

    Benzerga, Amine; Burgess, Brad

    2011-08-04

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

  12. FRACTURE FAILURE CRITERIA OF SOFC PEN STRUCTURE

    SciTech Connect (OSTI)

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

    2007-04-30

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

  13. Fault-Tolerant Quantum Computation with Higher-Dimensional Systems

    E-Print Network [OSTI]

    Daniel Gottesman

    1998-02-02

    Instead of a quantum computer where the fundamental units are 2-dimensional qubits, we can consider a quantum computer made up of d-dimensional systems. There is a straightforward generalization of the class of stabilizer codes to d-dimensional systems, and I will discuss the theory of fault-tolerant computation using such codes. I prove that universal fault-tolerant computation is possible with any higher-dimensional stabilizer code for prime d.

  14. Microstructures and Rheology of a Limestone-Shale Thrust Fault 

    E-Print Network [OSTI]

    Wells, Rachel Kristen

    2011-02-22

    AND RHEOLOGY OF A LIMESTONE-SHALE THRUST FAULT A Thesis by RACHEL KRISTEN WELLS Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December... 2010 Major Subject: Geology MICROSTRUCTURES AND RHEOLOGY OF A LIMESTONE-SHALE THRUST FAULT A Thesis by RACHEL KRISTEN WELLS Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment...

  15. Fault Detection, Diagnostics and Optimmization using BIG Data Analytics 

    E-Print Network [OSTI]

    Bonifay, X.

    2013-01-01

    buildings. Reduce footprint. ESL-IC-13-10-58a Proceedings of the 13th International Conference for Enhanced Building Operations, Montreal, Quebec, October 8-11, 2013 About IFCS ? Headquartered in Quebec, CANADA ? Founded in 1993 ? Y-Y Growth..., Equipment longevity, Occupant comfort ESL-IC-13-10-58a Proceedings of the 13th International Conference for Enhanced Building Operations, Montreal, Quebec, October 8-11, 2013 Fault Detection and Diagnostics - FDD Fault detection and diagnostics (FDD...

  16. Neural net application to transmission line fault detection and classification 

    E-Print Network [OSTI]

    Rikalo, Igor

    1994-01-01

    . So far, several NN implementations for various fault diagnosis problems have been reported in the literature. A number of papers describing NN applications in pov er systems categorized in appropriate groups can be found in [19, 20]. 1. 3. Thesis... important issue for stable and reliable operation of pov;er systems. The main target of the fault analysis are circuit breaker and protection relay operations. The task of the analysis is to reach a conclusion about the current state of the electrical...

  17. A Compiler for Fault-Tolerant High Level Quantum Circuits

    E-Print Network [OSTI]

    Alexandru Paler; Ilia Polian; Kae Nemoto; Simon J. Devitt

    2015-09-07

    Fault-tolerant quantum error correction is an absolute necessity for any quantum architecture destined to tackle interesting, large-scale quantum algorithms. The theoretical formalism of quantum error correction codes, fault-tolerant circuit constructions, gate decompositions and relevant optimisations have been well founded for nearly two decades. However, at this point we still do not have a reliable compiler to adapt a high level circuit description to a fully fault-tolerant, error corrected description. There are many technical hurdles to this, including dynamic circuit constructions that occur due to teleportation protocols necessary to achieve fault-tolerance with commonly used error correction codes. We combine multiple results to develop a package that takes any high level quantum circuit consisting of CNOT, Toffoli, Controlled-$\\sqrt{X}$ and arbitrary single qubit rotations and converts it to a equivalent quantum circuit employing ancillary protocols needed for fault-tolerant error correction. We call this representation the (I)initialisation, (C)NOT, (M)measurement representation (ICM) and consists of an initialisation layer of qubits into one of four distinct states, a massive array of CNOT operations that implement the relevant algorithmic decompositions and fault-tolerant ancillary protocols and a series of time ordered $X$- and $Z$-basis measurements. Our package will output either a standard circuit description or a canonical geometric structure that represents its implementation for topological quantum codes that can be further optimised and implemented on actual quantum hardware.

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

    E-Print Network [OSTI]

    Scully, Jennifer Eva

    2015-01-01

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

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

    E-Print Network [OSTI]

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

    2010-01-01

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

  20. Area of Interest 1, CO2 at the Interface. Nature and Dynamics of the Reservoir/Caprock Contact and Implications for Carbon Storage Performance

    SciTech Connect (OSTI)

    Mozley, Peter; Evans, James; Dewers, Thomas

    2014-10-31

    We examined the influence of geologic features present at the reservoir/caprock interface on the transmission of supercritical CO2 into and through caprock. We focused on the case of deformation-band faults in reservoir lithologies that intersect the interface and transition to opening-mode fractures in caprock lithologies. Deformation-band faults are exceeding common in potential CO2 injection units and our fieldwork in Utah indicates that this sort of transition is common. To quantify the impact of these interface features on flow and transport we first described the sedimentology and permeability characteristics of selected sites along the Navajo Sandstone (reservoir lithology) and Carmel Formation (caprock lithology) interface, and along the Slickrock Member (reservoir lithology) and Earthy Member (caprock lithology) of the Entrada Sandstone interface, and used this information to construct conceptual permeability models for numerical analysis. We then examined the impact of these structures on flow using single-phase and multiphase numerical flow models for these study sites. Key findings include: (1) Deformation-band faults strongly compartmentalize the reservoir and largely block cross-fault flow of supercritical CO2. (2) Significant flow of CO2 through the fractures is possible, however, the magnitude is dependent on the small-scale geometry of the contact between the opening-mode fracture and the deformation band fault. (3) Due to the presence of permeable units in the caprock, caprock units are capable of storing significant volumes of CO2, particularly when the fracture network does not extend all the way through the caprock. The large-scale distribution of these deformation-bandfault-to-opening-mode-fractures is related to the curvature of the beds, with greater densities of fractures in high curvature regions. We also examined core and outcrops from the Mount Simon Sandstone and Eau Claire Formation reservoir/caprock interface in order to extend our work to a reservoir/caprock pair this is currently being assessed for long-term carbon storage. These analyses indicate that interface features similar to those observed at the Utah sites 3 were not observed. Although not directly related to our main study topic, one byproduct of our investigation is documentation of exceptionally high degrees of heterogeneity in the pore-size distribution of the Mount Simon Sandstone. This suggests that the unit has a greater-than-normal potential for residual trapping of supercritical CO2.