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• 1. [Image] Assessment of geothermal resources of Caliente, Nevada

  	An assessment of the geothermal resources of Caliente, Nevada was made to provide information on resource characteristics and to site 2 (two) 500 ft (152 m) test wells to confirm the resource. The strategy ...
  	Citation × Citation Citation Abstract Copy Title: Assessment of geothermal resources of Caliente, Nevada Author: Trexler, D.T. Year: 1980 An assessment of the geothermal resources of Caliente, Nevada was made to provide information on resource characteristics and to site 2 (two) 500 ft (152 m) test wells to confirm the resource. The strategy used in the resource assessment employed a logical sequence of work elements that included 1) baseline data collection, 2) field investigations, 3) laboratory analyses and 4) data interpretation and synthesis. Airphoto interpretation indicated that a series of normal faults produced a stepped arrangement in the canyon walls on the west side of Meadow Valley Wash north of downtown Caiente. This area coincides with the area of known geothermal occurrences. Temperature measurements in existing wells indicate a rapid cooling of the geothermal waters as they mix with cold groundwater flows in Meadow Valley Wash. Soil mercury analyses range from 15 ppB to as high as 120 ppB. Trends in soil mercury content may indicate the presence of buried faults. Temperature measured in 2-meter deep auger holes indicated temperatures as high as 40/sup 0/C in an area north of the Lincoln County Medical Facility. Interpretation of chemical analyses, both major and minor, of waters collected from wells and streams in the area failed to conclusively show any mechanisms for the mixing of thermal and nonthermal waters. The selection of sites for the 2 (two) 500 ft (152 m) reservoir confirmation wells was made using the results of temperature surveys, geologic structure and historic observations; DOE/NV/10039-1 Title: Assessment of geothermal resources of Caliente, Nevada Author: Trexler, D.T. Year: 1980 An assessment of the geothermal resources of Caliente, Nevada was made to provide information on resource characteristics and to site 2 (two) 500 ft (152 m) test wells to confirm the resource. The strategy used in the resource assessment employed a logical sequence of work elements that included 1) baseline data collection, 2) field investigations, 3) laboratory analyses and 4) data interpretation and synthesis. Airphoto interpretation indicated that a series of normal faults produced a stepped arrangement in the canyon walls on the west side of Meadow Valley Wash north of downtown Caiente. This area coincides with the area of known geothermal occurrences. Temperature measurements in existing wells indicate a rapid cooling of the geothermal waters as they mix with cold groundwater flows in Meadow Valley Wash. Soil mercury analyses range from 15 ppB to as high as 120 ppB. Trends in soil mercury content may indicate the presence of buried faults. Temperature measured in 2-meter deep auger holes indicated temperatures as high as 40/sup 0/C in an area north of the Lincoln County Medical Facility. Interpretation of chemical analyses, both major and minor, of waters collected from wells and streams in the area failed to conclusively show any mechanisms for the mixing of thermal and nonthermal waters. The selection of sites for the 2 (two) 500 ft (152 m) reservoir confirmation wells was made using the results of temperature surveys, geologic structure and historic observations; DOE/NV/10039-1 Close

• 2. [Image] Geological and Geophysical Study of the Origin of the Warm Springs in Bath County, Virginia. Final Report, June 1, 1975--April 30, 1976

  	The results of heat flow determinations and a reconnaissance dipole electrical resistivity survey in Bath County are described. A geologic map was compiled based on published maps and supported by reconnaissance ...
  	Citation × Citation Citation Abstract Copy Title: Geological and Geophysical Study of the Origin of the Warm Springs in Bath County, Virginia. Final Report, June 1, 1975--April 30, 1976 Author: Costain, J.K. Year: 1976 The results of heat flow determinations and a reconnaissance dipole electrical resistivity survey in Bath County are described. A geologic map was compiled based on published maps and supported by reconnaissance geologic mapping in areas where published maps were not available. A regional bipole--dipole electrical resistivity survey was made in order to detect the presence of resistivity lows that might be associated with a geothermal system at depth. A single hole was drilled to a depth of approximately 300 m (approx. 1000 feet) to obtain a heat flow value that is representative of the area. The data were used to attempt to arrive at a model that unambiguously explains the origin of the thermal springs Title: Geological and Geophysical Study of the Origin of the Warm Springs in Bath County, Virginia. Final Report, June 1, 1975--April 30, 1976 Author: Costain, J.K. Year: 1976 The results of heat flow determinations and a reconnaissance dipole electrical resistivity survey in Bath County are described. A geologic map was compiled based on published maps and supported by reconnaissance geologic mapping in areas where published maps were not available. A regional bipole--dipole electrical resistivity survey was made in order to detect the presence of resistivity lows that might be associated with a geothermal system at depth. A single hole was drilled to a depth of approximately 300 m (approx. 1000 feet) to obtain a heat flow value that is representative of the area. The data were used to attempt to arrive at a model that unambiguously explains the origin of the thermal springs Close

• 3. [Image] A Time Domain Survey of the Los Alamos Region, New Mexico

  	A time domain electromagnetic sounding survey of the region surrounding the city of Los Alamos, New Mexico was carried out. The results show that a linear trough, trending northeast--southwest runs beneath ...
  	Citation × Citation Citation Abstract Copy Title: A Time Domain Survey of the Los Alamos Region, New Mexico Author: Williston, McNeiI and Associates Year: 1979 A time domain electromagnetic sounding survey of the region surrounding the city of Los Alamos, New Mexico was carried out. The results show that a linear trough, trending northeast--southwest runs beneath the city. The southern boundary is somewhat to the south of the city, the northern boundary was not established. The geoelectric section consists of three layers and the total thickness of the section is in excess of 3 000 m. The resistivities of the second layer are as low as 2.5 ..cap omega.. m. If the salinities are in the region of 7 000 ppm, the resistivities could indicate that water with a temperature of 150/sup 0/C may be found at a depth of 3 000 m. Title: A Time Domain Survey of the Los Alamos Region, New Mexico Author: Williston, McNeiI and Associates Year: 1979 A time domain electromagnetic sounding survey of the region surrounding the city of Los Alamos, New Mexico was carried out. The results show that a linear trough, trending northeast--southwest runs beneath the city. The southern boundary is somewhat to the south of the city, the northern boundary was not established. The geoelectric section consists of three layers and the total thickness of the section is in excess of 3 000 m. The resistivities of the second layer are as low as 2.5 ..cap omega.. m. If the salinities are in the region of 7 000 ppm, the resistivities could indicate that water with a temperature of 150/sup 0/C may be found at a depth of 3 000 m. Close

• 4. [Image] Geothermal Reservoir Categorization and Stimulation Study

  	Analyses of the fraction of geothermal wells that are dry (dry-hole fraction) indicate that geothermal reservoirs can be fitted into four basic categories: (i) Quaternary to late Tertiary sediments (almost ...
  	Citation × Citation Citation Abstract Copy Title: Geothermal Reservoir Categorization and Stimulation Study Author: Overton, H.L. Year: 1977 Analyses of the fraction of geothermal wells that are dry (dry-hole fraction) indicate that geothermal reservoirs can be fitted into four basic categories: (i) Quaternary to late Tertiary sediments (almost no dry holes); (ii) Quaternary to late Tertiary extrusives (approximately 20 percent dry holes); (iii) Mesozoic or older metamorphic rocks (approximately 25-30 percent dry holes); and (iv) Precambrian or younger rocks (data limited to Roosevelt Springs where 33 percent of the wells were dry). Failure of geothermal wells to flow economically is due mainly to low-permeability formations in unfractured regions. Generally the permeability correlates inversely with the temperature-age product and directly with the original rock porosity and pore size. However, this correlation fails whenever high-stress fields provide vertical fracturing or faulting, and it is the high-stress/low-permeability category that is most amenable to artificial stimulation by hydraulic fracturing, propellant fracturing, or chemical explosive fracturing. Category (i) geothermal fields (e.g., Cerro Prieto, Mexico; Niland, CA; East Mesa, CA) are not recommended for artificial stimulation because these younger sediments almost always produce warm or hot water. Most geothermal fields fit into category (ii) (e.g., Wairakei, New Zealand; Matsukawa, Japan; Ahuachapan, El Salvador) and in the case of Mt. Home, ID, and Chandler, AZ, possess some potential for stimulation. The Geysers is a category (iii) field, and its highly stressed brittle rocks should make this site amenable to stimulation by explosive fracturing techniques. Roosevelt Springs, UT, Well 9-1 is in category (iv) and is a flow failure. It represents a prime candidate for stimulation by hydraulic fracturing because it has a measured temperature of 227/sup 0/C, is cased and available for experimentation, and is within 900 m of an excellent geothermal producing well Title: Geothermal Reservoir Categorization and Stimulation Study Author: Overton, H.L. Year: 1977 Analyses of the fraction of geothermal wells that are dry (dry-hole fraction) indicate that geothermal reservoirs can be fitted into four basic categories: (i) Quaternary to late Tertiary sediments (almost no dry holes); (ii) Quaternary to late Tertiary extrusives (approximately 20 percent dry holes); (iii) Mesozoic or older metamorphic rocks (approximately 25-30 percent dry holes); and (iv) Precambrian or younger rocks (data limited to Roosevelt Springs where 33 percent of the wells were dry). Failure of geothermal wells to flow economically is due mainly to low-permeability formations in unfractured regions. Generally the permeability correlates inversely with the temperature-age product and directly with the original rock porosity and pore size. However, this correlation fails whenever high-stress fields provide vertical fracturing or faulting, and it is the high-stress/low-permeability category that is most amenable to artificial stimulation by hydraulic fracturing, propellant fracturing, or chemical explosive fracturing. Category (i) geothermal fields (e.g., Cerro Prieto, Mexico; Niland, CA; East Mesa, CA) are not recommended for artificial stimulation because these younger sediments almost always produce warm or hot water. Most geothermal fields fit into category (ii) (e.g., Wairakei, New Zealand; Matsukawa, Japan; Ahuachapan, El Salvador) and in the case of Mt. Home, ID, and Chandler, AZ, possess some potential for stimulation. The Geysers is a category (iii) field, and its highly stressed brittle rocks should make this site amenable to stimulation by explosive fracturing techniques. Roosevelt Springs, UT, Well 9-1 is in category (iv) and is a flow failure. It represents a prime candidate for stimulation by hydraulic fracturing because it has a measured temperature of 227/sup 0/C, is cased and available for experimentation, and is within 900 m of an excellent geothermal producing well Close