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• 1. [Image] Geological and Geophysical Analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California

  	The Coso Geothermal Exploration Hole number one (CGEH-1) was drilled in the Coso Hot Springs KGRA, California from September 2 to December 2, 1977. Chip samples were collected at ten foot intervals and ...
  	Citation × Citation Citation Abstract Copy Title: Geological and Geophysical Analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California Author: Galbraith, R.M. Year: 1978 The Coso Geothermal Exploration Hole number one (CGEH-1) was drilled in the Coso Hot Springs KGRA, California from September 2 to December 2, 1977. Chip samples were collected at ten foot intervals and extensive geophysical logging surveys were conducted to document the geologic character of the geothermal system as penetrated by CGEH-1. The major rock units encountered include a mafic metamorphic sequence and a leucogranite which intruded the metamorphic rocks. Only weak hydrothermal alteration was noted in these rocks. Drillhole surveys and drilling rate data indicate that the geothermal system is structurally controlled and that the drillhole itself was strongly influenced by structural zones. Water chemistry indicates that this geothermal resource is a hot-water rather than a vapor-dominated system. Several geophysical logs were employed to characterize the drillhole geology. The natural gamma and neutron porosity logs indicate gross rock type and the acoustic logs indicate fractured rock and potentially permeable zones. A series of temperature logs run as a function of time during and after the completion of Drilling were most Useful in delineating the zones of maximum heat flux. Convective heat flow and temperatures greater than 350/sup 0/F appear to occur only along an open fracture system encountered between depths of 1850 and 2775 feet. Temperature logs indicate a negative thermal gradient below 3000 feet Title: Geological and Geophysical Analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California Author: Galbraith, R.M. Year: 1978 The Coso Geothermal Exploration Hole number one (CGEH-1) was drilled in the Coso Hot Springs KGRA, California from September 2 to December 2, 1977. Chip samples were collected at ten foot intervals and extensive geophysical logging surveys were conducted to document the geologic character of the geothermal system as penetrated by CGEH-1. The major rock units encountered include a mafic metamorphic sequence and a leucogranite which intruded the metamorphic rocks. Only weak hydrothermal alteration was noted in these rocks. Drillhole surveys and drilling rate data indicate that the geothermal system is structurally controlled and that the drillhole itself was strongly influenced by structural zones. Water chemistry indicates that this geothermal resource is a hot-water rather than a vapor-dominated system. Several geophysical logs were employed to characterize the drillhole geology. The natural gamma and neutron porosity logs indicate gross rock type and the acoustic logs indicate fractured rock and potentially permeable zones. A series of temperature logs run as a function of time during and after the completion of Drilling were most Useful in delineating the zones of maximum heat flux. Convective heat flow and temperatures greater than 350/sup 0/F appear to occur only along an open fracture system encountered between depths of 1850 and 2775 feet. Temperature logs indicate a negative thermal gradient below 3000 feet Close

• 2. [Image] Heat Flow of Oregon

  	An extensive new heat flow and geothermal gradient data set for the State of Oregon is presented on a contour map of heat flow at a scale of 1:1,000,000 and is summarized in several figures and tables. ...
  	Citation × Citation Citation Abstract Copy Title: Heat Flow of Oregon Author: Blackwell, D.D. Year: 1978 An extensive new heat flow and geothermal gradient data set for the State of Oregon is presented on a contour map of heat flow at a scale of 1:1,000,000 and is summarized in several figures and tables. The 1:1,000,000 scale heat flow map is contoured at 20 mW/m/sup 2/ (0.5 HFU) intervals. Also presented are maps of heat flow and temperature at a depth of 1 km averaged for 1/sup 0/ x 1/sup 0/ intervals. Histograms and averages of geothermal gradient and heat flow for the State of Oregon and for the various physiographic provinces within Oregon are also included. The unweighted mean flow for Oregon is 81.3 +- 2.7 mW/m/sup 2/ (1.94 +- 0.06 HFU). The average unweighted geothermal gradient is 65.3 +- 2.5/sup 0/C/km. The average heat flow value weighted on the basis of geographic area is 68 +- 5 mW/m/sup 2/ (1.63 +- 0.12 HFU) and the average weighted geothermal gradient is 55.0 +- 5/sup 0/C/km Title: Heat Flow of Oregon Author: Blackwell, D.D. Year: 1978 An extensive new heat flow and geothermal gradient data set for the State of Oregon is presented on a contour map of heat flow at a scale of 1:1,000,000 and is summarized in several figures and tables. The 1:1,000,000 scale heat flow map is contoured at 20 mW/m/sup 2/ (0.5 HFU) intervals. Also presented are maps of heat flow and temperature at a depth of 1 km averaged for 1/sup 0/ x 1/sup 0/ intervals. Histograms and averages of geothermal gradient and heat flow for the State of Oregon and for the various physiographic provinces within Oregon are also included. The unweighted mean flow for Oregon is 81.3 +- 2.7 mW/m/sup 2/ (1.94 +- 0.06 HFU). The average unweighted geothermal gradient is 65.3 +- 2.5/sup 0/C/km. The average heat flow value weighted on the basis of geographic area is 68 +- 5 mW/m/sup 2/ (1.63 +- 0.12 HFU) and the average weighted geothermal gradient is 55.0 +- 5/sup 0/C/km Close

• 3. [Image] Low-Temperature Geothermal Reservoir Site Evaluation in Arizona. Quarterly Progress Report, November 1, 1977--January 31, 1978

  	The Department of Energy, Division of Geothermal Energy, has charged the Bureau of Geology and Mineral Technology, Geological Survey Branch with development of a cost-effective exploration program for ...
  	Citation × Citation Citation Abstract Copy Title: Low-Temperature Geothermal Reservoir Site Evaluation in Arizona. Quarterly Progress Report, November 1, 1977--January 31, 1978 Author: Hahman, W.R. Sr. Year: 1978 The Department of Energy, Division of Geothermal Energy, has charged the Bureau of Geology and Mineral Technology, Geological Survey Branch with development of a cost-effective exploration program for low- to moderate-temperature geothermal resources. As part of this program two or three demonstration projects in Arizona will be brought on stream. The site-specific exploration, evaluation and development program as well as the state wide reconnaissance exploration program is continuing. The compilation of data for the 1 : 500,000 geothermal energy resource map is continuing. Drafting and data collection for the 1 : 1,000,000 Preliminary map, Geothermal Energy Resources of Arizona, Geothermal Map No. 1, requested the first week in January by DOE/DGE is nearing completion. This preliminary map should be published in March, 1978. All outside projects are either complete or on schedule Title: Low-Temperature Geothermal Reservoir Site Evaluation in Arizona. Quarterly Progress Report, November 1, 1977--January 31, 1978 Author: Hahman, W.R. Sr. Year: 1978 The Department of Energy, Division of Geothermal Energy, has charged the Bureau of Geology and Mineral Technology, Geological Survey Branch with development of a cost-effective exploration program for low- to moderate-temperature geothermal resources. As part of this program two or three demonstration projects in Arizona will be brought on stream. The site-specific exploration, evaluation and development program as well as the state wide reconnaissance exploration program is continuing. The compilation of data for the 1 : 500,000 geothermal energy resource map is continuing. Drafting and data collection for the 1 : 1,000,000 Preliminary map, Geothermal Energy Resources of Arizona, Geothermal Map No. 1, requested the first week in January by DOE/DGE is nearing completion. This preliminary map should be published in March, 1978. All outside projects are either complete or on schedule Close

• 4. [Image] Stratigraphy and Alteration, 15 Shallow Thermal Gradient Holes, Roosevelt Hot Springs KGRA and Vicinity, Millard and Beaver Counties, Utah

  	Fifteen shallow thermal gradient drill holes were recently completed by Geothermal Power Corporation (GPCR) in the vicinity of the Roosevelt Hot Springs KGRA. Five holes penetrated Tertiary granitic rocks ...
  	Citation × Citation Citation Abstract Copy Title: Stratigraphy and Alteration, 15 Shallow Thermal Gradient Holes, Roosevelt Hot Springs KGRA and Vicinity, Millard and Beaver Counties, Utah Author: Hulen, J.B. Year: 1978 Fifteen shallow thermal gradient drill holes were recently completed by Geothermal Power Corporation (GPCR) in the vicinity of the Roosevelt Hot Springs KGRA. Five holes penetrated Tertiary granitic rocks and Precambrian gneiss east of the KGRA. Seven holes completed entirely in alluvium near the southwestern corner of the KGRA encountered a near-surface marker horizon of Pleistocene pumice and perlite. Maximum calculated alluvial sedimentation rates since initial deposition of this pumice and perlite range from 1 foot in 12,500 years to 1 foot in 2,300 years. Three holes east of the Mineral Mountains penetrated late Cenozoic basaltic andesite beneath a thin veneer of alluvium. All 15 GPCR drill holes appear to be peripheral to a central zone of anomalously high thermal gradient and low resisitivity delineated by previous investigations. GPCR-8 and -14, however, are characterized by high heat flow and relatively abundant manganese oxide mineralization, which may reflect a favorable hydrologic system controlling thermal fluid flow at depth. These holes thus seem most encouraging for discovery of a deeper high-temperature geothermal resource Title: Stratigraphy and Alteration, 15 Shallow Thermal Gradient Holes, Roosevelt Hot Springs KGRA and Vicinity, Millard and Beaver Counties, Utah Author: Hulen, J.B. Year: 1978 Fifteen shallow thermal gradient drill holes were recently completed by Geothermal Power Corporation (GPCR) in the vicinity of the Roosevelt Hot Springs KGRA. Five holes penetrated Tertiary granitic rocks and Precambrian gneiss east of the KGRA. Seven holes completed entirely in alluvium near the southwestern corner of the KGRA encountered a near-surface marker horizon of Pleistocene pumice and perlite. Maximum calculated alluvial sedimentation rates since initial deposition of this pumice and perlite range from 1 foot in 12,500 years to 1 foot in 2,300 years. Three holes east of the Mineral Mountains penetrated late Cenozoic basaltic andesite beneath a thin veneer of alluvium. All 15 GPCR drill holes appear to be peripheral to a central zone of anomalously high thermal gradient and low resisitivity delineated by previous investigations. GPCR-8 and -14, however, are characterized by high heat flow and relatively abundant manganese oxide mineralization, which may reflect a favorable hydrologic system controlling thermal fluid flow at depth. These holes thus seem most encouraging for discovery of a deeper high-temperature geothermal resource Close

• 5. [Image] Evaluation and Targeting of Geothermal Energy Resources in the Southeastern United States Progress Report, Apr 1, 1977--Jun 30, 1977

  	The objective of this research is to develop and apply targeting procedures for the evaluation of low-temperature radiogenically-derived geothermal resources in the eastern United States utilizing geological, ...
  	Citation × Citation Citation Abstract Copy Title: Evaluation and Targeting of Geothermal Energy Resources in the Southeastern United States Progress Report, Apr 1, 1977--Jun 30, 1977 Author: Costain, J.K. Year: 1977 The objective of this research is to develop and apply targeting procedures for the evaluation of low-temperature radiogenically-derived geothermal resources in the eastern United States utilizing geological, geochemical, and geophysical data. Detailed study of the Winnsboro complex, South Carolina, is continuing as part of a broader project to provide insight into the behavior of uranium and thorium in syn- and postmetamorphic granitic plutons Title: Evaluation and Targeting of Geothermal Energy Resources in the Southeastern United States Progress Report, Apr 1, 1977--Jun 30, 1977 Author: Costain, J.K. Year: 1977 The objective of this research is to develop and apply targeting procedures for the evaluation of low-temperature radiogenically-derived geothermal resources in the eastern United States utilizing geological, geochemical, and geophysical data. Detailed study of the Winnsboro complex, South Carolina, is continuing as part of a broader project to provide insight into the behavior of uranium and thorium in syn- and postmetamorphic granitic plutons Close

• 6. [Image] Geothermal Investigations in Idaho. Part 8. Heat Flow Study of the Snake River Plain Region, Idaho

  	The Snake River Plain of Idaho has recent lava flows and a large number of thermal springs and wells. A heat flow study was initiated which, together with available geological and geophysical information, ...
  	Citation × Citation Citation Abstract Copy Title: Geothermal Investigations in Idaho. Part 8. Heat Flow Study of the Snake River Plain Region, Idaho Author: Brott, C.A. Year: 1976 The Snake River Plain of Idaho has recent lava flows and a large number of thermal springs and wells. A heat flow study was initiated which, together with available geological and geophysical information, allows a better definition of the geothermal resource and evaluation of the geothermal potential. Local geothermal anomalies were not the objects of this study and have not been studied in detail. The quality of the heat flow values obtained varies as interpretation was necessary to determine geothermal gradients for many of the holes which had disturbances. A major problem in determining the heat flow values is the lack of knowledge of the in situ porosity of the rocks. The heat flow values obtained for the Eastern Snake River Plain are from shallow wells (< 200 m), hence the heat flow there is low (< 0.5 HFU) because of the water movement in the Snake Plain aquifer. The anomalous regional heat flow pattern around the Snake River Plain, together with other geophysical and geological data, suggest the presence of a major crustal heat source. With the exception of the area of the Snake Plain aquifer, high geothermal gradients were found in all areas of southern Idaho (40 to 100/sup 0/C/km). Temperatures hot enough for space heating can be found most anywhere in the Plain at relatively shallow depths (1 to 2 km). Temperatures hot enough for electrical power generation (200/sup 0/C) can be found beneath southern Idaho almost anywhere at depths of 3 to 4 kilometers. The Plain is fault bounded and hot water circulating along the fault zones from depths can be a very important geothermal resource at shallow depths. The margins of the Plain have the highest heat flow values, are the most faulted, and have possibly the highest geothermal resource potential Title: Geothermal Investigations in Idaho. Part 8. Heat Flow Study of the Snake River Plain Region, Idaho Author: Brott, C.A. Year: 1976 The Snake River Plain of Idaho has recent lava flows and a large number of thermal springs and wells. A heat flow study was initiated which, together with available geological and geophysical information, allows a better definition of the geothermal resource and evaluation of the geothermal potential. Local geothermal anomalies were not the objects of this study and have not been studied in detail. The quality of the heat flow values obtained varies as interpretation was necessary to determine geothermal gradients for many of the holes which had disturbances. A major problem in determining the heat flow values is the lack of knowledge of the in situ porosity of the rocks. The heat flow values obtained for the Eastern Snake River Plain are from shallow wells (< 200 m), hence the heat flow there is low (< 0.5 HFU) because of the water movement in the Snake Plain aquifer. The anomalous regional heat flow pattern around the Snake River Plain, together with other geophysical and geological data, suggest the presence of a major crustal heat source. With the exception of the area of the Snake Plain aquifer, high geothermal gradients were found in all areas of southern Idaho (40 to 100/sup 0/C/km). Temperatures hot enough for space heating can be found most anywhere in the Plain at relatively shallow depths (1 to 2 km). Temperatures hot enough for electrical power generation (200/sup 0/C) can be found beneath southern Idaho almost anywhere at depths of 3 to 4 kilometers. The Plain is fault bounded and hot water circulating along the fault zones from depths can be a very important geothermal resource at shallow depths. The margins of the Plain have the highest heat flow values, are the most faulted, and have possibly the highest geothermal resource potential Close

• 7. [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

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

  	A study was made to determine the origin of the warm springs and to evaluate the geothermal resource potential of the area in the vicinity of the Warm Springs anticline in Bath and Alleghany Counties, ...
  	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 A study was made to determine the origin of the warm springs and to evaluate the geothermal resource potential of the area in the vicinity of the Warm Springs anticline in Bath and Alleghany Counties, Virginia. Phase 1 of the study was the compilation of a geologic map based on published maps and supported by reconnaissance geologic mapping in areas where published maps were not available. Phase II consisted of a regional bipole-dipole electric resistivity survey made in order to detect the presence of resistivity lows that might be associated with a geothermal system at depth. Phase III involved the drilling of a single hole to a depth of approximately 300 m to obtain a heat flow value that is representative of the area. The above data were used to arrive at a model that unambiguously explains the origin of thermal springs. It is concluded that the warm springs constitute a geothermal resource for low temperature application such as space heating (LBS) 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 A study was made to determine the origin of the warm springs and to evaluate the geothermal resource potential of the area in the vicinity of the Warm Springs anticline in Bath and Alleghany Counties, Virginia. Phase 1 of the study was the compilation of a geologic map based on published maps and supported by reconnaissance geologic mapping in areas where published maps were not available. Phase II consisted of a regional bipole-dipole electric resistivity survey made in order to detect the presence of resistivity lows that might be associated with a geothermal system at depth. Phase III involved the drilling of a single hole to a depth of approximately 300 m to obtain a heat flow value that is representative of the area. The above data were used to arrive at a model that unambiguously explains the origin of thermal springs. It is concluded that the warm springs constitute a geothermal resource for low temperature application such as space heating (LBS) Close