918 Matching Results

Search Results

Advanced search parameters have been applied.

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

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

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

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 time. The most active period recorded occurred just after production resumed in the immediate area of the monitor well. Mapping the microearthquakes using the hodogram technique indicates the events occur along linear trends which corroborate known structural trends of the field. Seismicity trends were defined both parallel and perpendicular to the regionally defined maximum horizontal stress direction. Seventy-three good quality events were recorded, in a cumulative 24 hour period, from which structures were mapped up to 3000 ft from the monitor well. 13 refs., 9 figs.
Date: February 6, 1990
Creator: Rutledge, J. T. & Albright, J. N.
Partner: UNT Libraries Government Documents Department

Geological investigation of shaft mine in Devonian limestone in Kansas City, Missouri and other potentially dry excavated subsurface space in part of the Forest City Basin

Description: A high quality limestone is currently being mined from a deep shaft mine (1072 feet) in Middle Devonian rocks (Callaway) within the city limits of Kansas City, Missouri. About 15 acres of essentially dry space (room and pillar) with up to 14-foot ceilings have been developed. There are few natural joints observable in the rock within the mine. Some of these are periodically damp. More than 80% of the mine is dry. Saltwater from aquifers (Pennsylvanian) cut by the shaft accumulates behind the shaft at the pump station at 850 feet and at the bottom of the shaft (Devonian-Ordovician rocks). As long as the pumps lift the water to the surface, the mine can be kept relatively dry. Grouting of the aquifer's rocks in the shaft may seal off that source of water. The Burlington limestone of the Mississippian System is potentially mineable on the property now developed. The Burlington limestone, the Middle Devonian limestone, and the Kimmswick (Middle Ordovician) limestone are all potentially mineable by shaft mining in the northern part of Greater Kansas City and northward into the Forest City Basin.
Date: October 1, 1977
Creator: Goebel, E. D.
Partner: UNT Libraries Government Documents Department

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

Massive hydraulic fracturing experiment No. 1 Home Federal well, Uintah County, Utah

Description: Two massive hydraulic fracturing experiments were performed on two separate gas-bearing intervals of Mesaverde sandstones in the No. 1 Home Federal well located in Uintah County, Utah. Water-base gel carrying sand proppant was used as the frac medium and the limited entry technique was used for injection. The first experiment was carried out on an interval containing 112 ft of net pay between 10,014 and 10,202 ft. Pre-frac production capacity was estimated to be 60+ MCF/D. Post-frac production capacity was significantly less, presumably attributable to a limited lateral extent of inherent formation permeability. The second experiment was carried out on an interval containing 85 ft of net pay between 7826 and 9437 ft. Pre-frac production capacity of 33 MCF/D was increased by MHF to an initial 500 MCF/D and to a relatively stabilized 155 MCF/D within four months following the treatment.
Date: July 1, 1977
Creator: Boardman, C. R.
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

New thermoluminescence techniques for mineral exploration

Description: The thermoluminescence of carbonate host rock in the vicinity of known lead-zinc and lead-zinc-fluorite mineralization was reexamined for possible development as an exploration technique. The measurements were made with equipment for determining the thermoluminescence spectrum at closely spaced temperature intervals. Radiation-induced thermoluminescence was also measured. Samples were studied from five localities in Mexico, Southwest Africa, and the United States. Four thermoluminescence properties were found to vary with ''distance-from-ore'' in a systematic manner. These include the glow peak intensity and temperature and the emission spectrum peak energy and full width at half-maximum. For example, in both limestone and dolomite, the high-temperature glow peak intensities are low or negligible within the ore and as the distance from the contact increases the intensity rises rapidly to a maximum, or maxima, and then decreases irregularly to constant value slightly above that in the ore. Depending on the thickness of the ore, the thermoluminescence characteristics associated with the mineralization extended from ten to a hundred or so meters from the ore host rock contact. 5 figures. (DLC)
Date: January 1, 1977
Creator: Levy, P W; Holmes, R J; Ypma, P J; Chen, C C & Swiderski, H S
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

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

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 significant 15.8% loss. This indicates that the loss of penetration rate due to wetting the rock while mist drilling is small but would be significant when drilling a long interval. The findings indicate that when drilling hard rocks at the surface with mist instead of air, a penetration rate loss of approximately 12% (compared to the drilling rate with air) will occur due to the effect of jetting the soapy water through the bit onto the formation being drilled.
Date: August 1, 1977
Creator: Williams, C. R.
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

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 is an indirect process and the model's ability to estimate reservoir properties cannot be judged solely on the quality of the match between field data and model predictions. The model's accuracy in determining reservoir characteristics must be independently verified in a closely controlled environment. In this study, the closely controlled laboratory environment was chosen to test the validity and accuracy of tracer flow models developed specifically for flow in fractured rocks. The laboratory tracer tests were performed by flowing potassium iodide (KI) through artificially fractured core samples. The tracer test results were then analyzed with several models to determine which best fit the measured data. A Matrix Diffusion model was found to provide the best match of the tracer experiments. The core properties, as estimated by the Matrix Diffusion model parameters generated from the indirect matching process, were then determined. These calculated core parameters were compared to the measured core properties and were found to be in agreement. This verifies the use of the Matrix Diffusion flow model in estimating fracture widths from tracer tests.
Date: May 1, 1987
Creator: Johns, R. A.
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

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 the U.S., but little is mined. Chapter 6 discusses underground excavations into granite-type rocks. Suggestions are given in the last chapter for further study. (DLC)
Date: December 1, 1976
Partner: UNT Libraries Government Documents Department

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 presented and the ranking of methods based on currently available data is discussed. Salt, shale, granite, and limestone are covered. (DLC)
Date: November 1, 1976
Partner: UNT Libraries Government Documents Department

Geologic characteristics of a portion of the Salton Sea geothermal field

Description: The examination of drill cuttings and core samples from the Magmamax Nos. 2 and 3 and Woolsey No. 1 wells indicate that the sequence of sedimentary rocks in the Salton Sea geothermal field from the surface to below 4000 ft can be divided into three categories: cap rock, unaltered reservoir rocks, and hydrothermally altered reservoir rocks. The cap rock extends from the surface to a depth of approximately 1100 ft in all three wells. There is evidence to suggest that the cap rock has undergone self-sealing through time as a result of the circulation of hot brine through the rocks. Essentially unaltered reservoir rocks extend from a depth of 1100 ft to approximately 3000 ft. The mineralogical and textural changes that occur at depth can be attributed to the process of hydrothermal alteration. Alteration has occurred in a chemically open system and the important variables in the alteration scheme have been temperature, permeability, brine composition, and rock composition. The transition from unaltered to altered reservoir rocks is marked by the replacement of calcite by epidote. The first appearance of epidote correlates reasonably well with the top of the alteration zone as determined in other studies by electric log analysis. Biotite and chlorite, potential indicators of alteration zones, are considered to be of detrital origin rather than hydrothermal origin. The primary effect of hydrothermal alteration on the reservoir rocks in the Salton Sea geothermal field has been the reduction of porosity and permeability with depth. Petrographic analysis indicates that porosity and permeability in the field is enhanced by the presence of fractures in shales. The geologic picture that emerges from spontaneous potential (SP) log correlation is that of a structural basin whose axis lies to the northwest of Magmamax No. 2. The data suggest that unaltered reservoir rocks on the periphery ...
Date: April 25, 1977
Creator: Tewhey, J. D.
Partner: UNT Libraries Government Documents Department

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 intermediate-strain rates on strength and fracture in limestone; and development and testing of a theoretical model for yielding and pore collapse in porous rocks. The specific technical objectives of the project is to understand the physical mechanisms and develop models for the creation of fractured material or rubble and the enhancement of permeability by underground high-explosive detonations. This understanding will benefit in situ energy and resource technologies that use high explosives to achieve or enhance recovery of underground resources.
Date: May 1, 1977
Creator: Schatz, J.; Kusubov, A.; Hearst, J.; Abey, A.; Snell, C. & Thigpen, L.
Partner: UNT Libraries Government Documents Department

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 hours. In the application described the method was used to locate the depths where hydraulic fractures were initiated in a hot dry rock geothermal well.
Date: January 1, 1977
Creator: Murphy, H. D.
Partner: UNT Libraries Government Documents Department

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 producing a circulation system within the hot rock by hydraulic fracturing to create a large crack connecting two drilled holes, then operating the system as a closed pressurized-water heat-extration loop. With the best input assumptions that present knowledge provides, the fluid-flow and heat-exchange calculations indicate that unpumped (buoyant) circulation through a large hydraulic fracture can maintain a commercially useful rate of heat extraction throughout a usefully long system life. With a power cycle designed for the temperature of the fluid produced, total capital investment and generating costs are estimated to be at least competitive with those of fossil-fuel-fired and nuclear electric plants. This paper discusses the potential of the hot dry rock resource, various heat extraction concepts, prediction of reservoir performance, and economic factors, and summarizes recent progress in the LASL field program.
Date: January 1, 1977
Creator: Tester, J. W. & Smith, M. C.
Partner: UNT Libraries Government Documents Department

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 buildup of dissolved and suspended material in water as it is circulated through the fractured region. Chemical treatment methods, involving the selective dissolution of quartz (SiO/sub 2/), a major component of granite, with sodium carbonate solutions have been employed to increase the in situ permeability of the rock matrix. Laboratory measurements have concentrated on identifying the effects of temperature, pH and chemical additives on the solubility of granite samples taken from the two test wellbores. Promising results from these solubility experiments are tested in a laboratory-scale circulating system to examine kinetic parameters influencing rock dissolution and reprecipitation (scaling) under conditions that simulate the in situ reservoir and heat exchange environments.
Date: January 1, 1977
Creator: Tester, J. W.; Holley, C. E. Jr. & Blatz, L. A.
Partner: UNT Libraries Government Documents Department