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Geothermal energy and the utility market -- the opportunities and challenges for expanding geothermal energy in a competitive supply market: Proceedings

Description: Each year the Geothermal Division of the US Department of Energy conducts an in-depth review of its entire geothermal R D program. The conference serves several purposes: a status report on current R D activities, an assessment of progress and problems, a review of management issues, and a technology transfer opportunity between DOE and the US geothermal city. This year's conference, Program Review X, was held in San Francisco on March 24--26, 1992. The theme of the review, Geothermal Energy an… more
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department
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(In-situ permeability determination and fracture characterization using elastic waves)

Description: Fractures or permeable structures in reservoirs are of great importance in the exploration and production of hydrocarbons. Heterogeneous layers in the formation are also of major significance. A very good example of such heterogeneous and permeable structures is the sand-shale sequence found in sedimentary formations. Full waveform acoustic logging offers an effective tool for characterizing these structures. The current technique most commonly used for modeling borehole acoustic wave propagati… more
Date: January 1, 1992
Creator: Cheng, A. C. H.
Partner: UNT Libraries Government Documents Department
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Simulation of fluid-rock interactions in a geothermal basin. Final report. [QUAGMR (quasi-active geothermal reservoir)]

Description: General balance laws and constitutive relations are developed for convective hydrothermal geothermal reservoirs. A fully interacting rock-fluid system is considered; typical rock-fluid interactions involve momentum and energy transfer and the dependence of rock porosity and permeability upon the fluid and rock stresses. The mathematical model also includes multiphase (water/steam) effects. A simple analytical model is employed to study heat transfer into/or from a fluid moving in a porous mediu… more
Date: September 1, 1975
Creator: Garg, S. K.; Blake, T. R.; Brownell, D. H. Jr.; Nayfeh, A. H. & Pritchett, J. W.
Partner: UNT Libraries Government Documents Department
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Energy extraction characteristics of hot dry rock geothermal systems

Description: The LASL Hot Dry Rock Geothermal Energy Project is investigating methods to extract energy at useful temperatures and rates from naturally heated crustal rock in locations where the rock does not spontaneously yield natural steam or hot water at a rate sufficient to support commercial utilization. Several concepts are discussed for application to low and high permeability formations. The method being investigated first is intended for use in formations of low initial permeability. It involves p… more
Date: January 1, 1977
Creator: Tester, J. W. & Smith, M. C.
Partner: UNT Libraries Government Documents Department
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Depositional sequence analysis and sedimentologic modeling for improved prediction of Pennsylvanian reservoirs (Annex 1)

Description: Interdisciplinary studies of the Upper Pennsylvanian Lansing and Kansas City groups have been undertaken in order to improve the geologic characterization of petroleum reservoirs and to develop a quantitative understanding of the processes responsible for formation of associated depositional sequences. To this end, concepts and methods of sequence stratigraphy are being used to define and interpret the three-dimensional depositional framework of the Kansas City Group. The investigation includes… more
Date: January 1, 1992
Creator: Watney, W. L.
Partner: UNT Libraries Government Documents Department
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Drilling rate changes when air drilling is switched to mist drilling. [Claystone]

Description: Eight shallow (30-foot-deep) holes were drilled in four formations to determine if the reduction in penetration rate that usually occurs when air drilling is changed to mist drilling might be due to the physical action of drilling a wet, soapy rock. The results showed an average loss of 9.3%, with the greatest loss occurring in limestone. The softest formation (claystone) showed only a 1.2% reduction in penetration rate; the two sandstones averaged 10.0-percent loss; and the limestone showed a … more
Date: August 1, 1977
Creator: Williams, C. R.
Partner: UNT Libraries Government Documents Department
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Characteristics of American coals in relation to their conversion into clean energy fuels. Quarterly technical progress report, July--September 1975

Description: Twenty-one coal samples have been collected and characterized. Sixty coals have been provided to other agencies at their request. The capability of controlling coal characteristics during preparation is being developed: large variations in volatile content occur within a given raw coal but, by controlling the preparation, a uniform product with the devised specifications can be produced. Studies have begun on the suitability of various coals and cokes for use in pressurized fixed bed gasifiers.… more
Date: December 1, 1975
Creator: Spackman, W.; Davis, A.; Walker, P. L.; Lovell, H. L.; Essenhigh, R. H.; Vastola, F. J. et al.
Partner: UNT Libraries Government Documents Department
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Fluid injection profiles: modern analysis of wellbore temperature survey

Description: Exact and approximate solutions for heat flow in a fluid injection well are presented. By using the approximate results, temperature surveys can be quickly analyzed in the field, and the well depths where fluids leave and the departing flow rates at these depths can be precisely determined. Although this method eliminates the need for indigenous and post injection shut-in temperatures, several surveys must be taken just before and during the injection period which can be as short as several hou… more
Date: January 1, 1977
Creator: Murphy, H. D.
Partner: UNT Libraries Government Documents Department
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Update of 1972 status report on deep shaft studies

Description: The following aspects of shaft sinking are considered: the effects of geology, factors affecting shaft size, the conventional shaft sinking techniques and the newer mechanized methods, several representative or difficult shafts, and certain long-term problems and solutions. (LK)
Date: September 1, 1976
Partner: UNT Libraries Government Documents Department
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Solution chemistry and scaling in hot dry rock geothermal systems

Description: Field and laboratory experiments have focused on measuring the kinetics and equilibria associated with the transport of minerals from granite to circulating aqueous solutions. Presently two wellbores drilled to a depth of approximately 10,000 ft in the Valles Caldera region of the New Mexico Jemez mountains permit closed-loop circulation of fluid through a hydraulically fractured granite geothermal reservoir containing rock at 200/sup 0/C. Field measurements have dealth primarily with the build… more
Date: January 1, 1977
Creator: Tester, J. W.; Holley, C. E. Jr. & Blatz, L. A.
Partner: UNT Libraries Government Documents Department
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Adsorption of water vapor on reservoir rocks

Description: Progress is reported on: adsorption of water vapor on reservoir rocks; theoretical investigation of adsorption; estimation of adsorption parameters from transient experiments; transient adsorption experiment -- salinity and noncondensible gas effects; the physics of injection of water into, transport and storage of fluids within, and production of vapor from geothermal reservoirs; injection optimization at the Geysers Geothermal Field; a model to test multiwell data interpretation for heterogen… more
Date: July 1, 1993
Partner: UNT Libraries Government Documents Department
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Microseismic monitoring of the Chaveroo oil field, New Mexico

Description: Microseismicity was monitored in the Chaveroo oil field in southeastern New Mexico during, and for 5 weeks following, a pressurized stimulation of a well being prepared as an injector for a water flood operation. Three-thousand barrels of water were injected into the reservoir over a 5.5-hour period. Little seismicity was detected during the stimulation. Intermittent monitoring over a 5-week period following the injection indicated detectable seismicity occurring with activity levels varying in… more
Date: February 6, 1990
Creator: Rutledge, J. T. & Albright, J. N.
Partner: UNT Libraries Government Documents Department
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Evaluation of salt and mine rock disposal. Project No. 76-283. [Storing or disposing of mined rocks considered]

Description: Studies are being performed on the isolation of nuclear waste in geological formations; this would entail constructing an underground mine in selected rock strata for waste storage. Rocks removed from the mine during construction must be either disposed of permanently or temporarily stored for later backfill into the mine. Several methods of storing or disposing of the mined rock are discussed in this report. The technical feasibility, cost, advantages and disadvantages of each method are prese… more
Date: November 1, 1976
Partner: UNT Libraries Government Documents Department
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Injection through fractures

Description: Tracer tests are conducted in geothermal reservoirs as an aid in forecasting thermal breakthrough of reinjection water. To interpret tracer tests, mathematical models have been developed based on the various transport mechanisms in these highly fractured reservoirs. These tracer flow models have been applied to interpret field tests. The resulting matches between the model and field data were excellent and the model parameters were used to estimate reservoir properties. However, model fitting i… more
Date: May 1, 1987
Creator: Johns, R. A.
Partner: UNT Libraries Government Documents Department
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Preliminary state-of-the-art survey: mining techniques for salt and other rock types

Description: This is a systematic review of the state-of-the-art of underground mining and excavation technology in the U.S. as applied to salt, limestone, shale, and granite. Chapter 2 covers the basic characteristics of these rock types, the most frequently used underground mining methods, shaft and slope entry construction, equipment, and safety and productivity data. Chapters 3 and 4 summarize underground salt and limestone mining in the U.S. Chapter 5 shows that large amounts of thick shale exist in th… more
Date: December 1, 1976
Partner: UNT Libraries Government Documents Department
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Terminal storage of radioactive waste in geologic formations

Description: The principal aim of the National Waste Terminal Storage (NWTS) program is to develop pilot plants and, ultimately, repositories in several different rock formations in various parts of the country. Rocks such as salt, shale, limestone, granite, schists, and serpentinite may all qualify as host media for the disposition of radioactive wastes in the proper environments. In general, the only requirement for any rock formation or storage site is that it contain any emplaced wastes for so long as i… more
Date: July 5, 1976
Creator: Lomenick, T. F.
Partner: UNT Libraries Government Documents Department
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Regenerative process for desulfurization of high temperature combustion and fuel gases. Quarterly progress report No. 3, October 1--December 31, 1976

Description: A regenerative process based on using carbon in coal ashes for lime regeneration has been studied. Ten sulfation/regeneration cycles using Greer limestone have been conducted in a TG system and there was no sign of weakening of the SO/sub 2/ sorption activity. Work on the regenerative process based on silicates is being continued. For pure silicates, the sulfation rate of the monocalcium silicate appeared to be higher than that of the calcined Greer limestone and dicalcium silicate; the latter … more
Date: January 1, 1976
Creator: Shen, M. S.; Kainz, F. B.; Farber, G. & Smol, R.
Partner: UNT Libraries Government Documents Department
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Incremental natural gas resources through infield reserve growth/secondary natural gas recovery. [Compartmented natural gas reservoir]

Description: The objectives of the Infield Growth/Secondary Natural Gas Recovery project have been: To establish how depositional and diagenetic heterogeneities in reservoirs of conventional permeability cause reservoir compartmentalization and, hence, incomplete recovery of natural gas. To document practical, field-oriented examples of reserve growth from fluvial and deltaic sandstones of the Texas gulf coast basin and to use these gas reservoirs as a natural laboratory for developing concepts and testing … more
Date: January 1, 1992
Creator: Finley, R. J. & Levey, R. A.
Partner: UNT Libraries Government Documents Department
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Rock Mechanics Project progress and results: rock fracture and pore collapse

Description: Problems in rock fracture and pore collapse were studied with the intent of understanding mechanisms of and developing models for rubble formation, permeability enhancement, and wave propagation. Results are reported for studies on explosive-induced fracture and fluid flow in a gas-bearing sandstone at confining pressures to simulate in situ conditions; explosive-induced fracture in a brittle plastic with multiple charges fired both simultaneously and sequentially; the effect of several interme… more
Date: May 1, 1977
Creator: Schatz, J.; Kusubov, A.; Hearst, J.; Abey, A.; Snell, C. & Thigpen, L.
Partner: UNT Libraries Government Documents Department
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Numerical simulation of reservoir compaction in liquid dominated geothermal systems

Description: A numerical model is introduced which simulates the effects of fluid production as well as reinjection on the vertical deformation of water dominated geothermal reservoirs. This program, based on an Integrated Finite Difference technique and Terzaghi's one-dimensional consolidation model, computes the transport of heat and water through porous media, and resulting pore volume changes. Examples are presented to show the effects of reservoir heterogeneities on the compaction of these hot water sy… more
Date: December 1, 1976
Creator: Lippmann, M. J.; Narasimhan, T. N. & Witherspoon, P. A.
Partner: UNT Libraries Government Documents Department
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Paleozoic stratigraphy of two areas in southwestern Indiana. [Pennsylvanian, Mississippian, Devonian, Silurian, and Ordovician]

Description: Two areas recommended for evaluation as solid waste disposal sites lie along the strike of Paleozoic rocks in southwestern Indiana. Thin Pennsylvanian rocks and rocks of the upper Mississippian are at the bedrock surface in maturely dissected uplands in both areas. The gross subsurface stratigraphy beneath both areas is the same, but facies and thickness variation in some of the subsurface Paleozoic units provide for some minor differences between the areas. Thick middle Mississippi carbonates … more
Date: September 1, 1976
Creator: Droste, J. B.
Partner: UNT Libraries Government Documents Department
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Characterization of reservoir rocks and fluids by surface electromagnetic transient methods

Description: The objectives of this research are to improve the interpretations of transient electromagnetic (TEM) measurements over two-dimensional subsurface structures. TEM is a surface electromagnetic method employed in fossil energy reservoir exploration and characterization. Electrical measurements find application in (i) assisting in fossil energy exploration mainly in areas where seismic methods yield inadequate data quality, such as volcanic covered terrain, permafrost areas, and the Rocky Mountain… more
Date: January 1, 1992
Creator: Hoekstra, P.; Blohm, M. W. (Blackhawk Geosciences, Inc., Golden, CO (United States)); Stoyer, C. H. (Interpex Ltd. (United States)) & James, B. A. (James Consulting Services (United States))
Partner: UNT Libraries Government Documents Department
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Decomposition of calcium sulfate: a review of the literature. [62 refs]

Description: One of the important issues related to fluidized bed combustion of fossil fuels is the subsequent handling and/or treatment of the partially sulfated lime material removed from the combustor. One alternative would be to regenerate the sulfated additive to recover the sulfur, which would be stored for use, and lime that would be recycled for reuse in the combustor. It is the purpose of this report to review the development of regeneration technology which has progressed rather slowly as compared… more
Date: December 1, 1976
Creator: Swift, W. M.; Panek, A. F.; Smith, G. W.; Vogel, G. J. & Jonke, A. A.
Partner: UNT Libraries Government Documents Department
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Development program on pressurized fluidized-bed combustion. Quarterly report, October--December 1975

Description: A development program on pressurized fluidized-bed combustion is being carried out in a bench-scale pilot plant capable of operating at 10-atm pressure. The concept involves burning fuels such as coal in a fluidized bed of particulate lime additive that reacts with the sulfur compounds formed during combustion to reduce air pollution. Nitrogen oxide emissions are also reduced at the combustion temperatures used, which are lower than those used in a conventional coal combustor. The CaSO/sub 4/ p… more
Date: January 1, 1976
Creator: Vogel, G. J.; Cunningham, P. T. & Fischer, J.
Partner: UNT Libraries Government Documents Department
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