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Mechanical transport in two-dimensional networks of fractures

Description: The objectives of this research are to evaluate directional mechanical transport parameters for anisotropic fracture systems, and to determine if fracture systems behave like equivalent porous media. The tracer experiments used to measure directional tortuosity, longitudinal geometric dispersivity, and hydraulic effective porosity are conducted with a uniform flow field and measurements are made from the fluid flowing within a test section where linear length of travel is constant. Since fluid … more
Date: April 1, 1984
Creator: Endo, H.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Permeability damage to natural fractures caused by fracturing fluid polymers

Description: Formation damage studies using artificially fractured, low-permeability sandstone cores indicate that viscosified fracturing fluids can severely restrict gas flow through these types of narrow fractures. These studies were performed in support of the Department of Energy's Multiwell Experiment (MWX). Extensive geological and production evaluations at the MWX site indicate that the presence of a natural fracture system is largely responsible for unstimulated gas production. The laboratory format… more
Date: April 1, 1988
Creator: Gall, B. L.; Sattler, A. R.; Maloney, D. R. & Raible, C. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Geothermal Injection Monitoring Project. Phase I status report, April 1981-April 1982

Description: The feasibility of using remote geophysical techniques to monitor the movement of injected brine has been evaluated. It was established that no single approach is likely to be identified that can be used to accurately monitor the precise location of the injected fluid. Several approaches have been considered in parallel because they add new dimensions to the existing monitoring capabilities, and are likely to cover a range of applications at a variety of geothermal sites. These include: microse… more
Date: August 13, 1982
Creator: Younker, L.; Hanson, J.; Didwall, E.; Kasameyer, P.; Smith, A.; Hearst, J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Initial results from the first Los Alamos hot dry rock energy system

Description: The pressurized-water loop for extraction of natural heat from dry crustal rock is, as this is written, eight weeks into its initial long-term continuous circulation test. During most of this time, flow-impedance through the man-made fracture system has decreased continuously so that, with a nearly constant pressure difference between injection and recovery wells, flow rate has increased steadily to the maximum capacity of the surface piping--about 16 liters per second. Temperature of water ent… more
Date: January 1, 1978
Creator: Smith, M.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hot dry rock, an alternate geothermal energy resource: a challenge for instrumentation

Description: The natural internal heat from the Earth is one of the cleanest, nearly inexhaustible energy sources. The hot dry rock that composes most of the Earth's crust has the potential of becoming one of the largest reservoirs of energy economically available in the near future. The Los Alamos Scientific Laboratory, for the past five years, has been working toward exploiting this very abundant, clean energy source. The LASL technique to demonstrate the technical and economic feasibility of extracting h… more
Date: January 1, 1978
Creator: Dennis, B.R. & Horton, E.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal drawdown and recovery of singly and multiply fractured hot dry rock reservoirs

Description: To calculate heat extraction and thermal recovery in hot dry rock geothermal reservoirs, a computer code was written to solve the differential equations for rock-water heat conduction and convection by finite differences. Temperature versus time functions for multiple fractures separated by various spacings are presented in dimensional and in nondimensional plots. The results were specialized for the limiting case of a single fracture in unbounded rock and for the other limiting case where the … more
Date: April 1, 1978
Creator: Wunder, R. & Murphy, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Advances in materials science, Metals and Ceramics Division. Triannual progress report, February-May 1980

Description: Research is reported in the magnetic fusion energy and laser fusion energy programs, aluminium-air battery and vehicle research, geothermal research, nuclear waste management, basic energy science, and chemistry and materials science. (FS)
Date: August 1, 1980
Creator: Truhan, J.J. & Gordon, K.M. (eds.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Stimulation model for lenticular sands: Volume 2, Users manual

Description: This User's Manual contains information for four fracture/proppant models. TUPROP1 contains a Geertsma and de Klerk type fracture model. The section of the program utilizing the proppant fracture geometry data from the pseudo three-dimensional highly elongated fracture model is called TUPROPC. The analogous proppant section of the program that was modified to accept fracture shape data from SA3DFRAC is called TUPROPS. TUPROPS also includes fracture closure. Finally there is the penny fracture a… more
Date: July 1, 1987
Creator: Rybicki, E.F.; Luiskutty, C.T.; Sutrick, J.S.; Palmer, I.D.; Shah, G.H. & Tomutsa, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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E-Division semiannual report. Progress report, December 1, 1976--May 30, 1977. [LASL]

Description: Detector research and development are described first. Then, briefer reports are given on research on the following topics: electronic temperature monitoring and identification for livestock, electromagnetic probing (for fracture mapping), fiber optics for downhole instrumentation (for weapons testing), adaptive control applied to HVAC systems, energy environmental simulator, and high-temperature electronics. Engineering support (development projects, program support, instrumentation support) a… more
Date: November 1, 1977
Creator: Kelley, P.A. (comp.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microstructure and yield strength effects on hydrogen and tritium induced cracking in HERF (high-energy-rate-forged) stainless steel

Description: Rising-load J-integral measurements and falling-load threshold stress intensity measurements were used to characterize hydrogen and tritium induced cracking in high-energy-rate-forged (HERF) 21-6-9 stainless steel. Samples having yield strengths in the range 517--930 MPa were thermally charged with either hydrogen or tritium and tested at room temperature in either air or high-pressure hydrogen gas. In general, the hydrogen isotopes reduced the fracture toughness by affecting the fracture proce… more
Date: January 1, 1989
Creator: Morgan, M. J. & Tosten, M. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calibration models for fractured igneous rock environments

Description: At the present time, geophysical well logs are not calibrated for igneous and metamorphic lithologies or for fracture porosity. These geologic conditions are routinely encountered in geothermal reservoirs and geothermal fields. Three large calibration models or test pits are presently being fabricated. Each calibration model will be constructed of large stone blocks which have a cored-borehole and wire-sawn simulated fractures. Details of the test pit size, simulated fracture locations, rock ty… more
Date: January 1, 1980
Creator: Mathews, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Progress with field investigations at Stripa

Description: It is generally agreed that the most practicable method of isolating nuclear wastes from the biosphere is by deep burial in suitable geologic formations. Such burial achieves a high degree of physical isolation but raises questions concerning the rate at which some of these wastes may return to the biosphere through transport by groundwater. Any suitable repository site will be disturbed first by the excavation of the repository and second by the thermal pulse caused by the radioactive decay of… more
Date: February 1, 1980
Creator: Witherspoon, P.A.; Cook, N.G.W. & Gale, J.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tests pits for calibrating well logging equipment in fractured hard-rock environment

Description: The calibration facility consists of three pits containing fine-grained granite, coarse-grained granite, and medium-grained metamorphosed granodiorite. Each pit contains large quarried blocks of rock that are 8 ft octagons and form a 20 ft stack. The blocks are saturated with water and sealed in watertight fiberglass containers that are recessed so that the top of the upper block is approximately level with the ground. The blocks contain simulated fractures that are formed by the joints between… more
Date: January 1, 1985
Creator: Mathews, M. A.; Scott, J. H. & LaDelfe, C. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Review of the 1979 workshop on thermomechanical modeling for a hard rock waste repository

Description: The 1979 Workshop discussed and considered issues and needs in the areas of Modeling, Laboratory Measurements, Instruments and Field Measurements, and In-situ Tests and Model Validation. A set of conclusions and recommendations was developed, which focused on the necessity of treating the rock mass response to the waste emplaced in it. The conclusions dealt with characterizing the fracture system, determining the mechanical and thermal properties, developing an understanding of the physical pro… more
Date: January 1, 1980
Creator: Holzer, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Finite element analysis for the initiation of lamellar tearing in welded joints

Description: A numerical procedure using the finite element method is presented for predicting the initiation of lamellar tearing in fillet welded T-joints commonly employed in large structures. Starting with a prescribed geometry, the welding process is approximated by a known time-dependent volumetric heat source which simulates the arc heating and deposition of liquid metal. The transient nonlinear thermal and stress problems are then solved using finite element computer codes. Results of the elastic-pla… more
Date: January 1, 1980
Creator: Krieg, R. D. & Thomas, R. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low enthalpy convective system in Western Ohio

Description: A distinct positive anomaly in the temperatures of the shallow (Pleistocene) aquifers along the Cincinnati-Findlay Arch in Western Ohio coincides with a low geothermal gradient. A conceptual model of convective currents associated with a tensional fault and/or fracture system along the crest of the Arch is suggested as an explanation of the anomaly. Hydrochemical information indicates that various quantities of warmer ground water, with the composition characteristics of deep bedrock aquifers, … more
Date: January 1, 1980
Creator: Cannon, Melinda S.; Tabet, Charles A. & Eckstein, Yoram
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetic induction technique for mapping vertical conductive fractures: status report

Description: Fracture mapping plays a vital role in the production of energy from hot dry rock. Many fracture mapping techniques are summarized, and their merits discussed. Of these methods, one based on magnetic induction appears to be well suited for the hot dry rock application. As of August 1977, the status is given here of the development of a fracture mapping instrument using magnetic induction. The basic analysis and electronic design have been completed. Detailed mechanical design and fabrication re… more
Date: December 1, 1977
Creator: Landt, J. A.; Rowley, J. C.; Neudecker, J. W. & Koelle, A. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Overview of geotechnical methods to characterize rock masses

Description: The methods that are used to characterize discontinuous rock masses from a geotechnical point of view are summarized. Emphasis is put on providing key references on each subject. The topics of exploration, in-situ stresses, mechanical properties, thermal properties, and hydraulic properties are addressed.
Date: December 1, 1981
Creator: Heuze, F.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal depletion of a geothermal reservoir with both fracture and pore permeability

Description: A method for estimating the useful lifetime of a reservoir in porous rock where the injection and production wells intersect a fracture system is presented. Equations were derived for the pore-fluid and fracture-fluid temperatures averaged over large regions of the geothermal field. Problems such as incomplete areal sweep and interfingering of cool and hot fluids are ignored. Approximate equations relating average temperatures to the heat flowing from rock to fluid were developed, and their use… more
Date: August 10, 1976
Creator: Kasameyer, P.W. & Schroeder, R.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The LBL geothermal reservoir technology program

Description: The main objective of the DOE/GD-funded Geothermal Reservoir Technology Program at Lawrence Berkeley Laboratory is the development and testing of new and improved methods and tools needed by industry in its effort to delineate, characterize, evaluate, and exploit hydrothermal systems for geothermal energy. This paper summarizes the recent and ongoing field, laboratory, and theoretical research activities being conducted as part of the Geothermal Reservoir Technology Program. 28 refs., 4 figs.
Date: March 1, 1991
Creator: Lippmann, M.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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