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Deep drilling technology for hot crystalline rock (open access)

Deep drilling technology for hot crystalline rock

The development of Hot Dry Rock (HDR) geothermal systems at the Fenton Hill, New Mexico site has required the drilling of four deep boreholes into hot, Precambrian granitic and metamorphic rocks. Thermal gradient holes, four observation wells 200 m (600 ft) deep, and an exploration core hole 800 m (2400 ft) deep guided the siting of the four deep boreholes. Results derived from the exploration core hole, GT-1 (Granite Test No. 1), were especially important in providing core from the granitic rock, and establishing the conductive thermal gradient and heat flow for the granitic basement rocks. Essential stratigraphic data and lost drilling-fluid zones were identified for the volcanic and sedimentary rocks above the contact with the crystalline basement. Using this information drilling strategies and well designs were then devised for the planning of the deeper wells. The four deep wells were drilled in pairs, the shallowest were planned and drilled to depths of 3 km in 1975 at a bottom-hole temperature of nearly 200/sup 0/C. These boreholes were followed by a pair of wells, completed in 1981, the deepest of which penetrated the Precambrian basement to a vertical depth of 4.39 km at a temperature of 320/sup 0/C.
Date: January 1, 1984
Creator: Rowley, J.C.
Object Type: Article
System: The UNT Digital Library
Environmental monitoring final report: groundwater chemical analyses (open access)

Environmental monitoring final report: groundwater chemical analyses

This report presents the results of analyses of groundwater qualtiy at the SRC-I Demonstration Plant site in Newman, Kentucky. Samples were obtained from a network of 23 groundwater observation wells installed during previous studies. The groundwater was well within US EPA Interim Primary Drinking Water Standards for trace metals, radioactivity, and pesticides, but exceeded the standard for coliform bacteria. Several US EPA Secondary Drinking Water Standards were exceeded, namely, manganese, color, iron, and total dissolved solids. Based on the results, Dames and Moore recommend that all wells should be sterilized and those wells built in 1980 should be redeveloped. 1 figure, 6 tables.
Date: February 1, 1984
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Gold in the Black Pine Mining District, Southeast Cassia County, Idaho (open access)

Gold in the Black Pine Mining District, Southeast Cassia County, Idaho

A report about base and precious metals in the Black Pine mining district in the Black Pine Mountains . Two different types of mineral deposits are identified.
Date: 1984
Creator: Brady, Bruce T.
Object Type: Report
System: The UNT Digital Library
Icelandic basaltic geothermal field: A natural analog for nuclear waste isolation in basalt (open access)

Icelandic basaltic geothermal field: A natural analog for nuclear waste isolation in basalt

Analog studies of Icelandic geothermal fields have shown that the design of nuclear waste repositories in basalt can benefit by comparison to the data base already available from the development of these geothermal fields. A high degree of similarity exists between these two systems: their petrology, groundwater geochemistry, mineral solubilities, hydrologic parameters, temperature ranges, water-rock redox equilibria, hydrothermal pH values, and secondary mineralogies all show considerable overlap in the range of values. The experimentally-simulated hydrothermal studies of the basaltic nuclear waste repository rocks have, at this time, produced a data base that receives a strong confirmation from the Icelandic analog. Furthermore, the Icelandic analog should eventually be employed to extrapolate into higher and lower temperatures, into longer time-base chemical comparisons, and into more realistic mineral deposition studies, than have been possible in the laboratory evaluations of the nuclear waste repository designs. This eventual use of the Icelandic analog will require cooperative work with the Icelandic Geological Survey. 46 refs., 4 figs., 2 tabs.
Date: November 21, 1984
Creator: Ulmer, G. C. & Grandstaff, D. E.
Object Type: Report
System: The UNT Digital Library
Map Showing Outcrops of Pre-Quaternary Basaltic Rocks, Basin and Range Province, Oregon (open access)

Map Showing Outcrops of Pre-Quaternary Basaltic Rocks, Basin and Range Province, Oregon

From introduction: This map report is one of a series of geologic and hydrologic maps covering all or parts of States within the Basin and Range province of the western United States. The map reports contain information on subjects that characterize the geohydrology of the province, including the ground-water hydrology, ground-water quality, surface distribution of selected rock types, tectonic conditions, areal geophysics, Pleistocene lakes and marshes, and mineral and energy resources.
Date: 1984
Creator: Jenness, Jane E.; Sargent, K. A. & Lopez, David A.
Object Type: Report
System: The UNT Digital Library
Workshop on hydrologic and geochemical monitoring in the Long Valley Caldera: proceedings (open access)

Workshop on hydrologic and geochemical monitoring in the Long Valley Caldera: proceedings

A workshop reviewed the results of hydrologic and geochemical monitoring in the Long Valley caldera. Such monitoring is being done to detect changes in the hydrothermal system induced by ongoing magmatic and tectonic processes. Workshop participants discussed the need to instrument sites for continuous measurements of several parameters and to obtain additional hydrologic and chemical information from intermediate and deep drill holes. In addition to seismic and deformation monitoring, programs are currently in progress to monitor changes in the discharge characteristics of hot springs, fumaroles, and soil gases, as well as pressures and temperatures in wells. Some hydrochemical parameters are measured continuously, others are measured monthly or at longer intervals. This report summarizes the information presented at the hydrologic monitoring workshop, following the workshop agenda which was divided into four sessions: (1) overview of the hydrothermal system; (2) monitoring springs, fumaroles, and wells; (3) monitoring gas emissions; and (4) conclusions and recommendations.
Date: October 1, 1984
Creator: Sorey, M. L.; Farrar, C. D. & Wollenberg, H. A.
Object Type: Article
System: The UNT Digital Library
Potential for a Low-Temperature Geothermal Resource Near Mackay, Idaho (open access)

Potential for a Low-Temperature Geothermal Resource Near Mackay, Idaho

Four water samples were collected from springs in the Mackay, Idaho area to investigate the potential for a direct-heat geothermal resource. The maximum measured temperature was 22 C for a spring south of Mackay. Calculation of the mineral equilibrium relationships in the calcium-bicarbonate water samples indicates that these samples equilibrated with the carbonate reservoir rocks. The temperatures of equilibration suggest that the subsurface temperatures of these water samples are probably no higher than measured surface temperatures.
Date: October 1, 1984
Creator: Sibbett, Bruce S. & Capuano, Regina M.
Object Type: Report
System: The UNT Digital Library
Geochemical engineering reference manual (open access)

Geochemical engineering reference manual

The following topics are included in this manual: physical and chemical properties of geothermal brine and steam, scale and solids control, processing spent brine for reinjection, control of noncondensable gas emissions, and goethermal mineral recovery. (MHR)
Date: January 1, 1984
Creator: Owen, L.B. & Michels, D.E.
Object Type: Report
System: The UNT Digital Library
Chemical Stimulation Treatment of the Rossi 21-19 Well Beowawe Geothermal Field (open access)

Chemical Stimulation Treatment of the Rossi 21-19 Well Beowawe Geothermal Field

The tests reported were part of the DOE Geothermal Reservoir Well Stimulation Program. This was an attempt to ameliorate near-wellbore restricted permeability in a well at a field where other wells flowed at high rates. The two stage treatment first injected HCl followed by a large volume of HCl-HF acid solution. This was a relatively inexpensive treatment, with costs shown. Injectivity tests showed a 2.2 fold increase in injectivity attributable to the second treatment, but mechanical complications with the well precluded an adequate production test. Flow of the fluid out into the formation was measured by Sandia using surface electrical potential. LANL detected microseismic events during the stimulation, which might be especially significant.
Date: January 1, 1984
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Porosity of coastal deltaic sandstones, Cerro Prieto geothermal field, Baja California, Mexico (open access)

Porosity of coastal deltaic sandstones, Cerro Prieto geothermal field, Baja California, Mexico

Core porosity values for sandstones and density log-derived porosities for sandstone-siltstone-shale sequences indicate a range from less than 1% to 40% at the Cerro Prieto geothermal field, Baja California, Mexico. Mean porosity values indicate that a general trend of decreasing porosities with increasing depth from 35% at 600 m to 10% at 2300 m is complicated by the 15 to 30% porosities in the 350/sup 0/C hot water zone at about 2700 m depth. Scanning electron microscopy documents secondary dissolution porosity, mineral overgrowths, and abundant clay minerals. Core permeability ranges from 0.1 to 1000 millidarcies for the more than 50 cores studied. The porosity variability indicates that geothermal systems provide an ideal setting for testing concepts of dissolution porosity and increased secondary dissolution permeability that could be useful for nuclear waste storage as well as petroleum reservoir engineering.
Date: April 1, 1984
Creator: Vonder Haar, S.P.
Object Type: Article
System: The UNT Digital Library
Groundwater chemistry along flow paths between a proposed repository site and the accessible environment (open access)

Groundwater chemistry along flow paths between a proposed repository site and the accessible environment

The Nevada Nuclear Waste Storage Investigations Program of the Department of Energy is investigating Yucca Mountain in the Nevada Test Site as a possible repository location. As part of this investigation, the groundwater from all pumped wells in and near the site has been sampled and analyzed; the results are reported in this document. The speciation and solubility of nuclear waste elements in these groundwaters have been calculated using the EQ3/6 computer code. Estimates have also been made of the pH and Eh buffering capacity of the water/rock system of Yucca Mountain.
Date: November 1, 1984
Creator: Ogard, A.E. & Kerrisk, J.F.
Object Type: Report
System: The UNT Digital Library
Acoustic and electrical properties of Mexican geothermal rock samples (open access)

Acoustic and electrical properties of Mexican geothermal rock samples

Acoustic compressional and shear-wave velocities have been measured on a suite of ten sandstone samples obtained from wells in the Cerro Prieto geothermal field and on two rock samples from other Mexican geothermal fields. The samples were tested in both their dry and fully brine-saturated states at uniaxial stresses to 15 MPa. Electrical resistivities and associated phase angles have been measured on the same core samples as a function of frequency in the range 10 Hz to 10/sup 5/ Hz under drained conditions at hydrostatic confining stresses to 10 MPa. The electrical properties were measured on samples tested in their fully saturated state, using brines of two different concentrations.
Date: December 1, 1984
Creator: Contreras, E. A. & King, M. S.
Object Type: Article
System: The UNT Digital Library
Shallow magma targets in the western US (open access)

Shallow magma targets in the western US

Within the next few years a hole will be drilled into a shallow magma body in the western US for the purpose of evaluating the engineering feasibility of magma energy. This paper examines potential drilling sites for these engineering feasibility experiments. Target sites high on the list are ones that currently exhibit good geophysical and geological data for shallow magma and also have reasonable operational requirements. Top ranked sites for the first magma energy well are Long Valley, CA, and Coso/Indian Wells, CA. Kilauea, HI, also in the top group, is an attractive site for some limited field experiments. A number of additional sites offer promise as eventual magma energy sites, but sparsity of geophysical data presently prevents these sites from being considered for the first magma energy well.
Date: October 1, 1984
Creator: Hardee, H.C.
Object Type: Report
System: The UNT Digital Library
Low-temperature geothermal potential of the Ojo Caliente warm springs area, northern New Mexico (open access)

Low-temperature geothermal potential of the Ojo Caliente warm springs area, northern New Mexico

A detailed geochemical investigation of 17 waters (thermal and cold, mineralized and dilute) was performed in the Ojo Caliente-La Madera area. Two types of thermomineral waters have separate and distinctive geologic, geochemical, and geothermal characteristics. The water from Ojo Caliente Resort emerges with temperatures less than or equal to 54/sup 0/C from a Precambrian metarhyolite. Its chemistry, typically Na-HCO/sub 3/, has a total mineralization of 3600 mg/l. Isotopic studies have shown that the thermal water emerges from the springs and a hot well without significant mixing with the cold shallow aquifer of the valley alluvium. However, the cold aquifer adjacent to the resort does contain varying amounts of thermal water that originates from the warm spring system. Geothermometry calculations indicate that the thermal water may be as hot as 85/sup 0/C at depth before its ascent toward surface. Thermodynamic computations on the reaction states of numerous mineral phases suggest that the thermal water will not cause major scaling problems if the hot water is utilized for direct-use geothermal applications. By means of a network of very shallow holes, temperature and electrical conductivity anomalies have been found elsewhere in the valley around Ojo Caliente, and resistivity soundings have confirmed the presence …
Date: May 1, 1984
Creator: Vuataz, F. D.; Stix, J.; Goff, F. & Pearson, C. F.
Object Type: Report
System: The UNT Digital Library
Geochemistry, age and strontium isotope composition of late tertiary and quaternary basalts and andesites in western Nevada and their relation to geothermal potential. Final report, October 1, 1982-December 31, 1983 (open access)

Geochemistry, age and strontium isotope composition of late tertiary and quaternary basalts and andesites in western Nevada and their relation to geothermal potential. Final report, October 1, 1982-December 31, 1983

This research was undertaken to characterize the late Cenozoic volcanic rocks associated with active geothermal systems in west-central Nevada. Petrographic and microprobe, geochemical and isotopic analysis and age dating techniques were used to characterize these young volcanic rocks. These data were combined with the limited data previously reported in the literature on these same volcanic areas to interpret their petrogenesis. The overall characterization resulted from integrating the petrogenesis with a structural-tectonic model of the region. Potassium-argon isotopic ages ranging up to 14 million years were determined for eight localities within the Reno 1 x 2/sup 0/ study region. These ages are consistent with the morphology of the volcanic landforms, the active geothermal systems associated with them, and with other isotopic ages reported in the literature for these and similar rocks within the study region. Petrographic analysis of hand specimens and thin-sections indicated mineralogic assemblages of the respective rock types and specific mineral textures and phenocryst compositions and characteristics. These identifications were further substantiated by microprobe analysis of selected phenocrysts and groundmass phases. Classification of the respective rock types was also based on chemical composition and normative calculations using the program PETCAL. Basaltic andesites are identified and described for Steamboat Hills, …
Date: January 1, 1984
Creator: Fultz, L.A.; Bell, E.J. & Trexler, D.T.
Object Type: Report
System: The UNT Digital Library
Regional geothermal exploration in north central New Mexico. Final report (open access)

Regional geothermal exploration in north central New Mexico. Final report

A broad-based geothermal resource reconnaissance study covering Bernalillo, Los Alamos, Rio Arriba, San Miguel, Sandoval, Santa Fe, Taos, Torrance, and Valencia counties in north central New Mexico was conducted from June 15, 1981, through September 30, 1983. Specific activities included the compilation of actual temperature, bottom-hole temperature gradient, and geotemperature data; tabulation of water chemistry data; field collection of temperature-depth data from existing wells; and drilling of temperature gradient holes in the Ojo Caliente, San Ysidro, Rio Puerco, and Polvadera areas. The data collected were used to perform: (1) a regional analysis of the geothermal energy potential of north central New Mexico; (2) two site-specific studies of the potential relationship between groundwater constrictions and geothermal resources; (3) an evaluation of the geothermal energy potential at Santa Ana Pueblo; (4) a general analysis of the geothermal energy resources of the Rio Grande Rift, including specific data on the Valles Caldera; and (5) an evaluation of the use of geothermometers on New Mexico groundwaters. Separate abstracts were prepared for individual chapters.
Date: February 1, 1984
Creator: Icerman, L. (ed.)
Object Type: Report
System: The UNT Digital Library
Report on design, construction, and testing of CO/sub 2/ breakout system for geothermal brines (open access)

Report on design, construction, and testing of CO/sub 2/ breakout system for geothermal brines

A skid mounted test facility has been built for determining conditions at which CO/sub 2/ flashes from geothermal brines. The system has been checked and operated at one geothermal plant. It performed as designed. The equipment is designed to operate at temperatures and pressures typical of wells near Heber, California. (Nominally 180/sup 0/C and 300 to 500 psig). It has heat exchangers which can cool the brine to less than 70/sup 0/C. (The cooling water is recirculated after being cooled by a forced air heat exchanger). Breakout pressures can be determined for any temperature between 70/sup 0/C and wellhead temperature. An adjustable orifice provides final control on pressure required to initiate flashing. The orifice is at the bottom of a sight glass. A light beam shines through the sight glass and focuses on a photoelectric cell. The presence of bubbles scatters light and decreases the output of the cell. Results using the cell were more reproducible than those using the naked eye. Results from one test show a smooth curve over the temperature range 75/sup 0/C to 165/sup 0/C. Agreement between the experimental values and calculated ones is discussed.
Date: March 1, 1984
Creator: Robertus, R.J.; Shannon, D.W. & Sullivan, R.G.
Object Type: Report
System: The UNT Digital Library
Direct utilization of geothermal energy for Pagosa Springs, Colorado. Final report, June 1979-June 1984 (open access)

Direct utilization of geothermal energy for Pagosa Springs, Colorado. Final report, June 1979-June 1984

The Pagosa Springs Geothermal District Heating System was conceptualized, designed, and constructed between 1979 to 1984 under the US Department of Energy Program Opportunity Notice (PON) program to demonstrate the feasibility for utilizing moderate temperature geothermal resources for direct-use applications. The Pagosa Springs system successfully provides space heating to public buildings, school facilities, residences, and commercial establishments at costs significantly lower than costs of available conventional fuels. The Pagosa Springs project encompassed a full range of technical, institutional, and economic activities. Geothermal reservoir evaluations and testing were performed, and two productive approx.140/sup 0/F geothermal supply wells were successfully drilled and completed. Transmission and distribution system design, construction, startup, and operation were achieved with minimum difficulty. The geothermal system operation during the first two heating seasons has been fully reliable and well respected in the community. The project has proven that low to moderate-temperature waters can effectively meet required heating loads, even for harsh winter-mountain environments. The principal difficulty encountered has been institutional in nature and centers on the obtaining of the geothermal production well permits and the adjudicated water rights necessary to supply the geothermal hot water fluids for the full operating life of the system. 28 figs., 15 tabs.
Date: August 1, 1984
Creator: Goering, S.W.; Garing, K.L. & Coury, G.
Object Type: Report
System: The UNT Digital Library
Geologic and hydrologic research on the Moana geothermal system, Washoe County, Nevada. Final report October 1, 1982-December 31, 1983 (open access)

Geologic and hydrologic research on the Moana geothermal system, Washoe County, Nevada. Final report October 1, 1982-December 31, 1983

Combined geologic, geophysical, geochemical, and drilling exploration surveys were used to assess the Moana geothermal resource in Washoe County, Nevada, and to determine its relationship with nearby Steamboat Hot Springs. Moana is the largest single moderate-temperature resource in Nevada that supports geothermal space heating applications. Results show that the general geology and structure for the two systems is similar, but important differences exist with respect to reservoir rocks. Gravity data delineated the contact between important volcanic and sedimentary rocks in Moana, but contour trends did not correlate well with mapped faults. Fluid geochemistry data show major differences in bulk chemical composition, stable-light isotope ratios, and radiocarbon ages for Moana and Steamboat geothermal waters. Water level measurements in observation wells in Moana show simultaneous increasing and decreasing values in different sections of the geothermal area. Temperature-depth profiles changed little during the six-month monitoring period. Direct use of the resource is increasing and longer-lasting, more efficient down-hole heat exchangers are replacing previous equipment that was prone to scaling and corrosion. A computer program that calculates heat output for state-of-the-art heat exchangers is described. Recommendations for continued monitoring, heat exchanger design, and fluid reinjection studies are included. Data are available to government agencies …
Date: January 1, 1984
Creator: Flynn, T. & Ghusn, G. Jr.
Object Type: Report
System: The UNT Digital Library
New Mexico State University Campus geothermal demonstration project (open access)

New Mexico State University Campus geothermal demonstration project

This report presents the design, construction highlights, and performance of the New Mexico State University Campus Geothermal Demonstration Project at Las Cruces, New Mexico. Construction started in July 1981, first system use was January 1982, and the system was dedicated on April 21, 1982. Included herein are summary observations after two years of use. The geothermal hot water from New Mexico State University wells is used to heat potable water, which in turn provides 83 percent of the domestic hot water on the New Mexico State University campus, as well as space heat to two buildings, and for two heated swimming pools. The original system is providing service to 30 total buildings, with two additional buildings (150,000 square feet) in process of geothermal conversion.) The system overall performance has been excellent, except for geothermal well pump problems. In terms of operating efficiency, the system has exceeded the design parameters. In spite of abnormally high costs for well and pump repairs, the system has shown a positive cost avoidance of more than $118,000 for the first year of operation. For the first two full years of operation, the system has produced a net positive cost avoidance of more than $200,000. Payback …
Date: April 1, 1984
Creator: Cuniff, R.A.; Fisher, K.P. & Chintawongvanich, P.
Object Type: Report
System: The UNT Digital Library
Alumni J-TAC, October 1984 (open access)

Alumni J-TAC, October 1984

Alumni magazine of Tarleton State University providing information on events at the school and news about university students, staff, and alumni.
Date: October 1984
Creator: Tarleton State University
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
The Grassburr, Yearbook of Tarleton State University, 1984 (open access)

The Grassburr, Yearbook of Tarleton State University, 1984

Yearbook for Tarleton State University in Stephenville, Texas includes photos of and information about the school, student body, professors, and organizations. Index starts on page 246.
Date: Spring 1984
Creator: Tarleton State University
Object Type: Yearbook
System: The Portal to Texas History
Grass Burr (Weatherford, Tex.), Vol. 64, No. 3, Ed. 1 Friday, November 16, 1984 (open access)

Grass Burr (Weatherford, Tex.), Vol. 64, No. 3, Ed. 1 Friday, November 16, 1984

Student newspaper of Weatherford High School in Weatherford, Texas that includes school news and information along with advertising.
Date: November 16, 1984
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Alumni J-TAC, January 1984 (open access)

Alumni J-TAC, January 1984

Alumni magazine of Tarleton State University providing information on events at the school and news about university students, staff, and alumni.
Date: January 1984
Creator: Tarleton State University
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History