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Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite

Description: An equation of state previously used by the author is developed further and applied to geologic media. The equation is of the same form as the Murnaghan equation of state, but with the elastic constant terms replaced by the cohesive energy density (internal pressure), and the exponential term given as a sum of the Gruneisen parameter and the gaseous adiabatic exponent. Data for shock compression of silica, basalt, and dolomite are analyzed according to the equation.
Date: December 20, 1965
Creator: Rogers, L.A.
Partner: UNT Libraries Government Documents Department

Annual Report to Congress 1966

Description: Progress in the Plowshare program during 1966 was characterized by the upsurge of interest by industry in the contained applications of nuclear explosions for gas and oil stimulation, storage and disposal, recovery of oil from oil shales, and mining. Advances in the excavation area were limited to improved code calculations as no field experiments were conducted.
Date: October 31, 1966
Partner: UNT Libraries Government Documents Department

(Relative mobilities and transport mechanisms of trace elements during contact metamorphism of carbonate rocks). Progress report

Description: The main objective of this study is to investigate the relative mobilities and transport mechanisms of major, minor, and trace elements during the contact metamorphism of carbonate rocks. The large contrasts in chemical potentials of SiO/sub 2/, Al/sub 2/O/sub 3/, and CaO across a granitic pluton-limestone contact may induce metasomatism. In addition, rare earth and transition metal elements may act as tracers, and their redistribution during metamorphism may record convective cooling processes. The results of this study may have an application toward the problem of radioactive waste disposal and the degree to which radioactive nuclides may be expected to migrate during geologically significant periods of time.
Date: unknown
Partner: UNT Libraries Government Documents Department

Classification of public lands valuable for geothermal steam and associated geothermal resources

Description: The Organic Act of 1879 (43 USC 31) that established the US Geological Survey provided, among other things, for the classification of the public lands and for the examination of the geological structure, mineral resources, and products of the national domain. In order to provide uniform executive action in classifying public lands, standards for determining which lands are valuable for mineral resources, for example, leasable mineral lands, or for other products are prepared by the US Geological Survey. This report presents the classification standards for determining which Federal lands are classifiable as geothermal steam and associated geothermal resources lands under the Geothermal Steam Act of 1970 (84 Stat. 1566). The concept of a geothermal resouces province is established for classification of lands for the purpose of retention in Federal ownership of rights to geothermal resources upon disposal of Federal lands. A geothermal resources province is defined as an area in which higher than normal temperatures are likely to occur with depth and in which there is a resonable possiblity of finding reservoir rocks that will yield steam or heated fluids to wells. The determination of a known geothermal resources area is made after careful evaluation of the available geologic, geochemical, and geophysical data and any evidence derived from nearby discoveries, competitive interests, and other indicia. The initial classification required by the Geothermal Steam Act of 1970 is presented.
Date: January 1, 1973
Creator: Goodwin, L.H.; Haigler, L.B.; Rioux, R.L.; White, D.E.; Muffler, L.J.P. & Wayland, R.G.
Partner: UNT Libraries Government Documents Department

Development program on pressurized fluidized-bed combustion. Annual report, July 1, 1974--June 30, 1975

Description: The feasibility of using fluidized-bed combustors in power and steam plants is being evaluated. The concept involves burning fuels such as coal in a fluidized bed of either a naturally occurring, calcium-containing limestone or dolomite or in a synthetically prepared calcium-containing stone. The calcium oxide in the stone reacts with the sulfur released during combustion to form calcium sulfate, which remains in the bed, thus decreasing the level of SO/sub 2/ in the flue gas. Levels of NO/sub x/ in the flue gas are also low. The effect of operating variables and type of stone on the levels of SO/sub 2/ and NO/sub x/ is being determined. Behavior of trace elements during combustion has been preliminarily evaluated. The properties of a fluidized bed at minimum fluidization at different temperatures and pressures have been determined. The CaSO/sub 4/ produced in the combustion process is regenerated to CaO for reuse in the combustor by reductive decomposition at 1095/sup 0/C (2000/sup 0/F). The effects of operating variables on sulfur release during regeneration are being evaluated. Another regeneration process, solid-solid reaction of CaSO/sub 4/ with CaS, is also being investigated. Fundamental investigations of the kinetics of sulfation and regeneration reactions for the natural and synthetic stones are continuing. A model for the sulfation reaction is presented. The status of the new combustor andancillary regenerator equipment is discussed. (auth)
Date: July 1, 1975
Creator: Vogel, G.J.; Cunningham, P. & Fischer, J.
Partner: UNT Libraries Government Documents Department

Equation of state of rocks. Final report, 31 March 1973--1 Sep 1974

Description: The work described applies to the general problem of seismic coupling in geologic materials. In addition to work carried out during the past project year, important results from previous years were included so as to make the report as self contained as possible. Shock wave loading and release wave paths have been experimentally determined for Arkansas novaculite (a polycrystalline quartz rock), a perthitic feldspar, Nugget sandstone, dry and water-saturated Mount Helen tuff, Linden Hall limestone, dry and water-saturated Indiana limestone, and Blair dolomite. Multiple in-material stress and particle velocity gages were used to record stress-time and particle velocity-time profiles at several depths in specimens in the stress range from 60 to 500 kbar. Results are given.
Date: July 1, 1975
Creator: Murri, W. J.; Grady, D. E. & Mahrer, K. D.
Partner: UNT Libraries Government Documents Department

Geothermal investigations in Idaho. Part 2. An evaluation of thermal water in the Bruneau-Grand View area, southwest Idaho

Description: The Bruneau-Grand View area occupies about 1,100 square miles in southwest Idaho and is on the southern flank of the large depression in which lies the western Snake River Plain. The igneous and sedimentary rocks in the area range in age from Late Cretaceous to Holocene. The aquifers in the area have been separated into two broad units: (1) the volcanic-rock aquifers, and (2) the overlying sedimentary-rock aquifers. The Idavada Volcanics or underlying rock units probably constitute the reservoir that contains thermal water. An audio-magnetotelluric survey indicates that a large conductive zone having apparent resistivities approaching 2 ohm-meters underlies a part of the area at a relatively shallow depth. Chemical analysis of 94 water samples collected in 1973 show that the thermal waters in the area are of a sodium bicarbonate type. Although dissolved-solids concentrations of water ranged from 181 to 1,100 milligrams per litre (mg/1) in the volcanic-rock aquifers, they were generally less than 500 mg/1. Measured chloride concentrations of water in the volcanic-rock aquifers were less than 20 mg/1. Temperatures of water from wells and springs ranged from 9.5/sup 0/ to 83.0/sup 0/C. Temperatures of water from the volcanic-rock aquifers ranged from 40.0/sup 0/ to 83.0/sup 0/C, whereas temperatures of water from the sedimentary-rock aquifers seldom exceeded 35/sup 0/C. Aquifer temperatures at depth, as estimated by silica and sodium-potassium-calcium geochemical thermometers, probably do not exceed 150/sup 0/C. The gas in water from the volcanic-rock aquifers is composed chiefly of atmospheric oxygen and nitrogen. Methane gas (probably derived from organic material) was also found in some water from the sedimentary-rock aquifers.
Date: July 1, 1975
Creator: Young, H. W.; Whitehead, R. L.; Hoover, D. B. & Tippens, C. L.
Partner: UNT Libraries Government Documents Department

Geohydrological environmental effects of geothermal power production: Phase I. Final report

Description: Results are presented for the first phase of a three-phase research effort to develop reliable computer simulators whereby field information for a specific liquid- or vapor-dominated geothermal system can be used to predict reservoir performance and subsurface environmental effects due to production and reinjection of geothermal fluids. The environmental effects of interest include land surface subsidence, induced seismic activity, and pollution of freshwater aquifers by geothermal brines. The approach is to develop large-scale finite-difference and finite-element computer programs, based upon fundamental principles, and to validate these codes using both laboratory measurements and field data. During the first year, separate codes were developed for describing the multiphase multidimensional unsteady flow of steam and water in a heterogeneous geologic setting without rock deformation, and for calculating the response of a multidimensional rock matrix to prescribed pore pressure changes without specific consideration of fluid flow. Both of these codes were tested against analytic results and laboratory data, and the results of a few sample calculations are presented.
Date: September 1, 1975
Creator: Pritchett, J. W.; Garg, S. K.; Brownell, D. H. Jr. & Levine, H. B.
Partner: UNT Libraries Government Documents Department

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 medium. Numerical results show that for fluid velocities typical of geothermal systems (Reynolds number much less than 10), the fluid and the solid may be assumed to be in local thermal equilibrium. Mathematical formalism of Anderson and Jackson is utilized to derive a continuum species transport equation for flow in porous media; this method allows one to delineate, in a rigorous manner, the convective and diffusive mechanisms in the continuum representation of species transport. An existing computer program (QUAGMR) is applied to study upwelling of hot water from depth along a fault; the numerical results can be used to explain local temperature inversions occasionally observed in bore hole measurements.
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

Geologic feasibility of selected chalk-bearing sequences within the conterminous United States with regard to siting of radioactive-waste repositories

Description: Various geologic and hydrologic parameters are evaluated in relation to assessing the potential for repository storage of high-level radioactive wastes within several stratigraphic sequences dominated by chalks and chalky limestones. The former lithology is defined as a carbonate rock consisting mainly of very fine-grained particles of micritic calcite. Although chalks also contain coarser-grained particles such as shells of fossil foraminifera and non-calcitic minerals like quartz, most contain more than 90 percent micritic material. The latter represents broken fossil coccolith plates. The chalk-dominated formations discussed are exposed and underlie two different physiographic provinces which nevertheless display a general similarity in both being regions of extensive plains. The Niobrara Formation occurs mainly within the Great Plains province, while the Austin Chalk of Texas and the Selma Group of Alabama and Mississippi are located in the western and eastern Gulf Coastal Plain, respectively. The preliminary assessment is that chalk-bearing sequences show some promise and are deserving of added consideration and evaluation. Containment for hundreds of thousands of years would seem possible given certain assumptions. The most promising units from the three studied are the Niobrara Formation and Selma Group. Regional and local conditions make the Austin more suspect.
Date: November 1, 1975
Creator: Gonzales, S.
Partner: UNT Libraries Government Documents Department

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. Preliminary studies are being carried out on the feasibility of applying small angle x-ray scattering to the characterization of coal chars. Reactivity profiles and parameters for chars in air are markedly dependent upon the gaseous flow system used, indicating that char reactivity is determined by partial pressure of the reacting gas. Reactivities have been maximized by keeping the heat treatment temperature as low as possible, and allowing no soak time. The minerals kaolinite, dolomite, siderite, calcite, and pyrite are found not to be catalysts for the char-air reaction at 550/sup 0/C. The addition of coal to an oil-water-air emulsion considerably increases the heat flux from the flame to the water tubes during combustion. (auth)
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

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/ produced in the combustor is regenerated to CaO that is recycled to the combustor for removal of sulfur compounds. Information is presented on: hot testing of the new bench-scale regeneration system, TGA experiments on sulfation and regeneration rates of supported additives and on cyclic sulfation regeneration experiments, petrographic change occurring during half-calcination of dolomite, laboratory-scale experiments on the reaction of calcium sulfide with calcium sulfate, coal combustion reactions, and quality of fluidization and minimum fluidization velocity studies.
Date: January 1, 1976
Creator: Vogel, G. J.; Cunningham, P. T. & Fischer, J.
Partner: UNT Libraries Government Documents Department

Geotechnical studies of geothermal reservoirs

Description: It is proposed to delineate the important factors in the geothermal environment that will affect drilling. The geologic environment of the particular areas of interest are described, including rock types, geologic structure, and other important parameters that help describe the reservoir and overlying cap rock. The geologic environment and reservoir characteristics of several geothermal areas were studied, and drill bits were obtained from most of the areas. The geothermal areas studied are: (1) Geysers, California, (2) Imperial Valley, California, (3) Roosevelt Hot Springs, Utah, (4) Bacca Ranch, Valle Grande, New Mexico, (5) Jemez Caldera, New Mexico, (6) Raft River, Idaho, and (7) Marysville, Montona. (MHR)
Date: January 1, 1976
Creator: Pratt, H.R. & Simonson, E.R.
Partner: UNT Libraries Government Documents Department

Migration of plutonium and americium in the lithosphere

Description: When radionuclides are stored as wastes either in permanent repositories or in waste storage areas, the possibility of escape into the environment must be considered. Surface contamination and the transport and migration of radionuclides into the lithosphere through the agency of water are discussed. Water in the form of rain will inevitably wash contaminants into soils and thence into conducting rocks. The migration of radionuclides must follow widely varying paths. In porous rocks, water percolates easily under a slight pressure gradient and rapid movement of large volumes of water can result with concommitant transport of large amounts of contaminating materials. In relatively non-porous rocks such as Niagara limestones the transport meets much more resistance and the volumes of water conducted are correspondingly reduced. In such situations much of the migration of water and its solutes may be through cracks and fissures in the rock. Certain strata of rock or rock products may be almost impervious to flow of water and by this token may be considered to be an especially suitable container for long term safe storage of nuclear wastes, particularly if these strata are quiescent. A series of investigations was undertaken to examine the properties of rocks in acting as a retarding agent in the migration of radionuclides. The rocks that are discussed are Niagara limestone (chosen for its density and fine porosity), basalt from the National Reactor Test site, and Los Alamos tuff.
Date: January 1, 1976
Creator: Fried, S.; Friedman, A. M.; Hines, J. J.; Atcher, R. W.; Quarterman, L. A. & Volesky, A.
Partner: UNT Libraries Government Documents Department

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 two being similar. Procedures for particle strength test and for generating coal ash with controlled carbon content are being established. A micro-, semi-pilot plant for studying the regenerative processes is being constructed.
Date: January 1, 1976
Creator: Shen, M. S.; Kainz, F. B.; Farber, G. & Smol, R.
Partner: UNT Libraries Government Documents Department

Compression wave studies in Blair dolomite

Description: Dynamic compression wave studies have been conducted on Blair dolomite in the stress range of 0-7.0 GPa. Impact techniques were used to generate stress impulse input functions, and diffuse surface laser interferometry provided the dynamic instrumentation. Experimental particle velocity profiles obtained by this method were coupled with the conservation laws of mass and momentum to determine the stress-strain and stress-modulus constitutive properties of the material. Comparison between dynamic and quasistatic uniaxial stress-strain curves uncovered significant differences. Energy dissipated in a complete load and unload cycle differed by almost an order of magnitude and the longitudinal moduli differed by as much as a factor of two. Blair dolomite was observed to yield under dynamic loading at 2.5 GPa. Below 2.5 GPa the loading waves had a finite risetime and exhibited steady propagation. A finite linear viscoelastic constitutive model satisfactorily predicted the observed wave propagation. We speculate that dynamic properties of preexisting cracks provides a physical mechanism for both the rate dependent steady wave behavior and the difference between dynamic and quasistatic response.
Date: February 1, 1976
Creator: Grady, D. E.; Hollenbach, R. E.; Schuler, K. W. & Callender, J. F.
Partner: UNT Libraries Government Documents Department

Basal Ottawa Limestone, Chattanooga Shale, Floyd Shale, Porters Creek Clay, and Yazoo Clay in parts of Alabama, Mississippi and Tennessee as potential host rocks for underground emplacement of waste

Description: Impermeable rock units, preferably at least 500 feet thick and lying 1000 to 3000 feet below land surface, were sought in the region consisting roughly of the western /sup 3///sub 5/ths of Tennessee and the northern /sup 3///sub 5/ths of Alabama and Mississippi. All rock sequences, Cambrian through Eocene, were examined in varying detail, except the Cretaceous Selma Chalk and except the diapiric salt. These rocks were studied for their relative impermeable homogeneity, their continuity, their background of structural and seismic stability and their hydrologic associations. The Central Mississippi Ridge of north-central Mississippi is overlain by a long-stable mass of Porters Creek Clay 500-700 feet thick, in an area roughly 50-60 miles wide and about 150 miles long. The Yazoo Clay, where best developed in the west-central and southwest part of Mississippi, is in the 400-500 foot thickness range, but locally exceeds 500 feet. The entire area mapped is underlain by the Louann Salt which has produced many deep-seated salt domes and numerous piercement salt domes. Salt flow has complicated shallow structural geology throughout that area. The Chattanooga Shale rarely exceeds 60 feet in thickness in the region studied and is generally much thinner and is absent in many places. In the lower part of the Middle Ordovician (Ottawa Megagroup), the Murphreesboro and associated dense limestones appear to offer a potential disposal unit 250-400 feet thick, having the advantages of rock competency and freedom from association with prolific aquifers in the overburden or beneath. Other less conspicuous stratigraphic units are reviewed.
Date: February 28, 1976
Creator: Mellen, F. F.
Partner: UNT Libraries Government Documents Department

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 it takes for the radioactive materials to decay to innocuous levels. This requirement, though, is a formidable one as some of the wastes will remain active for periods of hundreds of thousands of years and the physical and chemical properties of rocks that govern circulating groundwater and hence containment, are difficult to determine and define. Nevertheless, there are many rock types and a host of areas throughout the country where conditions are promising for the development of waste repositories. Some of these are discussed below.
Date: July 5, 1976
Creator: Lomenick, T. F.
Partner: UNT Libraries Government Documents Department

Design of a water jet drill for development of geothermal resources. Progress report, June 1, 1976--August 1, 1976

Description: Research has concentrated on two areas: firstly, the laboratory testing of harder rock material such as granite and limestone, and secondly, the development of the field testing equipment and its preliminary proof-testing in the field.
Date: August 1, 1976
Creator: Summers, D. A. & Bushnell, D. J.
Partner: UNT Libraries Government Documents Department

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 is justified by comparing the results with solutions of the exact equations. The equations for the temperature decline can be solved quickly. In the model, fractures are characterized by three parameters: aperture w, permeability k/sub fr/, and spacings between fractures D. For certain values of these parameters, cool reinjected fluid in fractures may reach the production wells long before all the warm pore fluid has been tapped, shortening the useful lifetime of the field. The traditional (and important) problems of reservoir engineering, flow rate determination, drawdown, sweep patterns, etc. were ignored. Thus the results are most useful in providing a correction factor which can be applied to lifetime estimates obtained from a detailed simulation of a field assuming porous rock. That correction factor is plotted for clean fractures (k/sub fr/ = w/sup 2//12) as a function of w and D for several lifetime ranges. Small-scale fractures seen in cores from the Salton Sea Geothermal Field are too closely spaced to reduce lifetime estimates. However, large-scale fault systems exist within that field, and they are attractive drilling targets because they produce large flow rates. If large scale faults communicate between injection and production wells, they may reduce the useful lifetime of those wells.
Date: August 10, 1976
Creator: Kasameyer, P.W. & Schroeder, R.C.
Partner: UNT Libraries Government Documents Department

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 grade downward into clastics of lower Mississippian (Borden Group) and upper Devonian (New Albany Shale) rocks. Middle Devonian and Silurian rocks are dominated by carbonate lithologies. Upper Ordovician (Maquoketa Group) overly carbonates of middle Ordovician age. Thick siltstone and shale of the Borden Group-New Albany Shale zone and Maquoketa Group rocks should be suitable for repository development.
Date: September 1, 1976
Creator: Droste, J. B.
Partner: UNT Libraries Government Documents Department