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Three-dimensional mise-a-la-masse modeling applied to mapping fracture zones

Description: A numerical scheme applying the method of integral equations has been developed for borehole-to-borehole and borehole-to-surface modeling of the apparent resistivity response of a thin conductive body in a half-space; the inhomogeneity simulates a fracture zone. The algorithm is applicable for the direct-current case when the buried electrode is either inside (mise-a-la-masse) or outside (near-miss) the body. In implementing the scheme, the integral equation is transformed into a matrix equatio… more
Date: June 1, 1985
Creator: Beasley, C. W. & Ward, S. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pressure oscillations caused by momentum on shut in of a high rate well in a fractured formation

Description: Pressure transient testing techniques are an important part of reservoir and production testing procedures. These techniques are frequently used to determine practical information about underground reservoirs such as the permeability, porosity, liquid content, reservoir and liquid discontinuities and other related data. This information is valuable in helping to analyze, improve and forecast reservoir performance. This report is concerned with developing models for pressure transient well testi… more
Date: June 1, 1989
Creator: Bhatnagar, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Discrete-event simulation of nuclear-waste transport in geologic sites subject to disruptive events. Final report

Description: This report outlines a methodology to study the effects of disruptive events on nuclear waste material in stable geologic sites. The methodology is based upon developing a discrete events model that can be simulated on the computer. This methodology allows a natural development of simulation models that use computer resources in an efficient manner. Accurate modeling in this area depends in large part upon accurate modeling of ion transport behavior in the storage media. Unfortunately, developm… more
Date: June 19, 1980
Creator: Aggarwal, S.; Ryland, S. & Peck, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tracer test analysis of the Klamath Falls geothermal resource: a comparison of models

Description: Two tracer tests on doublet systems in a fractured geothermal system were carried out in Klamath Falls, Oregon. The purpose of the tests were to obtain data which would lead to information about the reservoir and to test the applicability of current tracer flow models. The results show rapid breakthrough times and indicate fracture flow with vigorous mixing of injector fluid before production of same. This leads to the idea that thermal breakthrough is not directly related to tracer breakthroug… more
Date: June 1, 1984
Creator: Johnson, S.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of retention processes and their effect on the analysis of tracer tests in fractured reservoirs

Description: Retention processes such as adsorption and diffusion into an immobile region can effect tracer movement through a fractured reservoir. This study has conducted experimental work and has developed a two-dimensional model to characterize retention processes. A method to directly determine some important flow parameters, such as the fracture aperture, from the analysis of tracer tests has been developed as a result of the new two-dimensional model. The experimental work consisted of batch experime… more
Date: June 1, 1984
Creator: Walkup, G.W. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of Thermally Induced Changes in Fractured Rock Permeability during Eight Years of Heating and Cooling at the Yucca Mountain Drift Scale Test

Description: We analyzed a data set of thermally induced changes in fractured rock permeability during a four-year heating (up to 200 C) and subsequent four-year cooling of a large volume, partially saturated and highly fractured volcanic tuff at the Yucca Mountain Drift Scale Test, in Nevada, USA. Permeability estimates were derived from about 700 pneumatic (air-injection) tests, taken periodically at 44 packed-off borehole intervals during the heating and cooling cycle from November 1997 through November … more
Date: June 1, 2008
Creator: Rutqvist, J.; Freifeld, B.; Min, K.-B.; Elsworth, D. & Tsang, Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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On Water Flow in Hot Fractured Rock -- A Sensitivity Study on theImpact of Fracture-Matrix Heat Transfer

Description: Dual-continuum models have been widely used in modeling flowand transport in fractured porous rocks. Among many other applications,dual-continuum approaches were utilized in predictive models of thethermal-hydrological conditions near emplacement tunnels (drifts) atYucca Mountain, Nevada, the proposed site for a radioactive wasterepository in the U.S. In unsaturated formations such as those at YuccaMountain, the magnitude of mass and heat exchange between the twocontinua fracture network and ma… more
Date: June 1, 2005
Creator: Birkholzer, Jens T. & Zhang, Yingqi
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of bonded composite doublers for the repair of oil recovery equipment.

Description: An unavoidable by-product of a metallic structure's use is the appearance of crack and corrosion flaws. Economic barriers to the replacement of these structures have created an aging infrastructure and placed even greater demands on efficient and safe repair methods. In the past decade, an advanced composite repair technology has made great strides in commercial aviation use. Extensive testing and analysis, through joint programs between the Sandia Labs FAA Airworthiness Assurance Center and th… more
Date: June 1, 2005
Creator: Roach, David W. & Rackow, Kirk A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ADVANCED INTEGRATION OF MULTI-SCALE MECHANICS AND WELDING PROCESS SIMULATION IN WELD INTEGRITY ASSESSMENT

Description: The potential to save trillions of BTU’s in energy usage and billions of dollars in cost on an annual basis based on use of higher strength steel in major oil and gas transmission pipeline construction is a compelling opportunity recognized by both the US Department of Energy (DOE). The use of high-strength steels (X100) is expected to result in energy savings across the spectrum, from manufacturing the pipe to transportation and fabrication, including welding of line pipe. Elementary examples … more
Date: June 30, 2008
Creator: Wilkowski, Gery M.; Rudland, David L.; Shim, Do-Jun; Brust, Frederick W. & Babu, Sundarsanam
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Aligned vertical fractures, HTI reservoir symmetry, and Thomsenseismic anisotropy parameters

Description: The Sayers and Kachanov (1991) crack-influence parametersare shown to be directly related to Thomsen (1986) weak-anisotropyseismic parameters for fractured reservoirs when the crack density issmall enough. These results are then applied to seismic wave propagationin reservoirs having HTI symmetry due to aligned vertical fractures. Theapproach suggests a method of inverting for fracture density from wavespeed data.
Date: June 27, 2007
Creator: Berryman, James G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Poroelastic modeling of seismic boundary conditions across afracture

Description: A fracture within a porous background is modeled as a thin porous layer with increased compliance and finite permeability. For small layer thickness, a set of boundary conditions can be derived that relate particle velocity and stress across a fracture, induced by incident poroelastic waves. These boundary conditions are given via phenomenological parameters that can be used to examine and characterize the seismic response of a fracture. One of these parameters, here it is called membrane perme… more
Date: June 29, 2006
Creator: Schoenberg, M.A. & Nakagawa, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DNAPL invasion into a partially saturated dead-end fracture

Description: The critical height for DNAPL entry into a partially watersaturated, dead-end fracture is derived and compared to laboratoryobservations. Experiments conducted in an analog, parallel-plate fracturedemonstrate that DNAPL accumulates above the water until the height ofthe DNAPL overcomes the sum of the capillary forces at the DNAPL-airinterface and at the DNAPL-water interface. These experiments also showthat DNAPL preferentially enters the water at locations where DNAPL haspreviously entered, an… more
Date: June 17, 2004
Creator: gwsu@lbl.gov
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Improved Miscible Nitrogen Flood Performance Utilizing Advanced Reservoir Characterization and Horizontal Laterals in a Class I Reservoir - East Binger (Marchand) Unit

Description: The DOE-sponsored project at the East Binger Unit is an investigation into the benefits of reservoir characterization and horizontal wells in this particular setting of geologic and recovery method. The geologic setting is a tight (average porosity of 7% and average permeability of less than 1 millidarcy) Pennsylvanian-age sandstone at about 10,000 feet, and the recovery method is a miscible nitrogen flood. The projected oil recovery of the East Binger Unit, prior to the initiation of this proj… more
Date: June 30, 2004
Creator: Sinner, Joe
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Continuous time random walk analysis of solute transport in fractured porous media

Description: The objective of this work is to discuss solute transport phenomena in fractured porous media, where the macroscopic transport of contaminants in the highly permeable interconnected fractures can be strongly affected by solute exchange with the porous rock matrix. We are interested in a wide range of rock types, with matrix hydraulic conductivities varying from almost impermeable (e.g., granites) to somewhat permeable (e.g., porous sandstones). In the first case, molecular diffusion is the only… more
Date: June 1, 2008
Creator: Cortis, Andrea; Cortis, Andrea & Birkholzer, Jens
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Time-dependent nuclide transport through backfill into a fracture

Description: This paper presents a transient analysis of radionuclide transport through backfill into a fissure. This report considers a waste canister surrounded by backfill in a borehole intersected by a fracture, in water-saturated rock. Radionuclides are released at a constant concentration C/sub s/ at the waste surface into the backfill. Ground water flows in the fissure. We assume no ground-water flow in the backfill, so that radionuclide transport through the backfill is controlled by molecular diffu… more
Date: June 1, 1987
Creator: Kang, C. H.; Chambre, P. L.; Lee, W. W. L. & Pigford, T. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analytic solution of pseudocolloid migration in fractured rock

Description: A form of colloid migration that can enhance or retard the migration of a dissolved contaminant in ground water is the sorption of the contaminant on the moving colloidal particulate to form pseudocolloids. In this paper we develop analytical solutions for the interactive migration of radioactive species dissolved in ground water and sorbed as pseudocolloids. The solute and pseudocolloids are assumed to undergo advection and dispersion in a one-dimensional flow field in planar fractures in poro… more
Date: June 1, 1989
Creator: Hwang, Y.; Pigford, T. H.; Lee, W. W. L. & Chambre, P. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Lawrence Livermore National Laboratory post-Loma Prieta earthquake initiative: Seismic analysis of an elevated portion of the Bay Bridge distribution system structure

Description: Because of the importance of earthquake safety for the citizens of California, and the potential devastating effects of future large earthquakes on the California economy, upper management at the Lawrence Livermore National Laboratory (LLNL) made a decision that LLNL should make available any unique laboratory resources to aid in post-earthquake studies. One area in which LLNL has attempted to help is in computer simulation of the performance of large scale transportation structures. The comput… more
Date: June 1, 1990
Creator: McCallen, D. & Goudreau, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of Kevlar 49 fibers by electron paramagnetic resonance. Final report, 20 May 1981-20 June 1982. [Radicals induced by ultraviolet or fracture]

Description: EPR was used to investigate the free radicals created in Kevlar 49 fibers by stress-induced and photo-induced macromolecular chain scissions. Mn/sup +2/ ions were identified from the EPR spectrum of frozen solutions of concentrated sulfuric acid containing Kevlar 49. Other ions present are Cu/sup +2/, and possibly Fe/sup +3/, Cr/sup +3/, and Ti/sup +3/. EPR lineshape anisotropy indicates that some of the metal ions and first coordinate spheres are oriented. The concentration of stress-induced r… more
Date: June 20, 1982
Creator: Brown, I.M. & Sandreczki, T.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Shallow seismic investigations of Devonian-shale gas production

Description: The foremost conclusion of this study is that fractured Devonian shale gas reservoirs, as exemplified by the Cottageville field, are detectable by seismic reflection methods. Further, the target is not particularly difficult, once the nature of the seismic anomaly is understood. The preferred exploration rationale is based on travel time anomalies related to lowered acoustic velocity within the gas-bearing zone. In the simplest case the travel time anomaly causes an apparent down-warp or sag in… more
Date: June 1, 1982
Creator: Williams, R. T.; Ruotsala, J. E.; Kudla, J. J. & Dunne, W. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanistic modeling of Zircaloy deformation and fracture in fuel element analysis

Description: A review is given of the comprehensive model developed in the 1960's at the Bettis Atomic Power Laboratory to explain the creep of Zircaloy during neutron irradiation and applied to fuel element analysis and design. The in-pile softening observed at low stresses was hypothesized to be due to a combination of the growth-directed Roberts-Cottrell yielding creep originally proposed for ..cap alpha..-uranium and the formation of point defect loops preferentially on certain planes in response to the… more
Date: June 1, 1985
Creator: Nichols, F.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Earth Sciences Division annual report 1989

Description: This Annual Report presents summaries of selected representative research activities from Lawrence Berkeley Laboratory grouped according to the principal disciplines of the Earth Sciences Division: Reservoir Engineering and Hydrology, Geology and Geochemistry, and Geophysics and Geomechanics. We are proud to be able to bring you this report, which we hope will convey not only a description of the Division's scientific activities but also a sense of the enthusiasm and excitement present today in… more
Date: June 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Status of lost circulation research

Description: This paper describes progress made in the Lost Circulation Technology Development Program over the period March, 1992--April, 1993. The program is sponsored at Sandia National Laboratories by the US Department of Energy, Geothermal division. The goal of the program is to develop technology to reduce lost circulation costs associated with geothermal drilling by 30--50%.
Date: June 1, 1993
Creator: Glowka, D. A.; Schafer, D. M.; Wright, E. K.; Whitlow, G. L. & Bates, C. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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