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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] Evaluation and Targeting of Geothermal Energy Resources in the Southeastern United States. Progress Report, October 1--December 31, 1977

  	Progress in the evaluation of low-temperature geothermal resources in the eastern United States utilizing geological, geochemical, and geophysical data is reported. Primary programmatic emphasis is now ...
  	Citation × Citation Citation Abstract Copy Title: Evaluation and Targeting of Geothermal Energy Resources in the Southeastern United States. Progress Report, October 1--December 31, 1977 Author: Costain, J.K. Year: 1978 Progress in the evaluation of low-temperature geothermal resources in the eastern United States utilizing geological, geochemical, and geophysical data is reported. Primary programmatic emphasis is now being placed on the confirmation of radiogenic resources beneath sediments of the Atlantic Coastal Plain. Collation of existing gravity and magnetic data available for the Atlantic Coastal Plain is complete, and modeling of selected negative gravity anomalies of the Cuffytown Creek (Edgefield) pluton, S.C., the Rolesville batholith, N.C., and the Petersburg granite, Va., is in progress. Maps showing the distribution of gravity stations for the states of Georgia, South Carolina, and North Carolina were prepared. A reconnaissance geologic map is being prepared of the Raleigh belt and Carolina slate belt rocks. The purpose of this study is to determine the relationship of the Rolesville batholith to the surrounding country rocks, and to provide a geologic base for the geophysical interpretation of Piedmont stratigraphy underlying Atlantic Coastal Plain sediments to the east Title: Evaluation and Targeting of Geothermal Energy Resources in the Southeastern United States. Progress Report, October 1--December 31, 1977 Author: Costain, J.K. Year: 1978 Progress in the evaluation of low-temperature geothermal resources in the eastern United States utilizing geological, geochemical, and geophysical data is reported. Primary programmatic emphasis is now being placed on the confirmation of radiogenic resources beneath sediments of the Atlantic Coastal Plain. Collation of existing gravity and magnetic data available for the Atlantic Coastal Plain is complete, and modeling of selected negative gravity anomalies of the Cuffytown Creek (Edgefield) pluton, S.C., the Rolesville batholith, N.C., and the Petersburg granite, Va., is in progress. Maps showing the distribution of gravity stations for the states of Georgia, South Carolina, and North Carolina were prepared. A reconnaissance geologic map is being prepared of the Raleigh belt and Carolina slate belt rocks. The purpose of this study is to determine the relationship of the Rolesville batholith to the surrounding country rocks, and to provide a geologic base for the geophysical interpretation of Piedmont stratigraphy underlying Atlantic Coastal Plain sediments to the east Close

• 3. [Image] Geologic Characteristics of a Portion of the Salton Sea Geothermal Field

  	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 ...
  	Citation × Citation Citation Abstract Copy Title: Geologic Characteristics of a Portion of the Salton Sea Geothermal Field Author: Tewhey; J.D. Year: 1977 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 Title: Geologic Characteristics of a Portion of the Salton Sea Geothermal Field Author: Tewhey; J.D. Year: 1977 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 Close

• 4. [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

• 5. [Image] Low-Temperature Geothermal Reservoir Site Evaluation in Arizona. Quarterly Progress Report, August 1, 1977--October 31, 1977

  	Progress in the development of a cost-effective exploration program for low- to moderate-temperature geothermal resources is reported. As part of this program two or three demonstration projects in Arizona ...
  	Citation × Citation Citation Abstract Copy Title: Low-Temperature Geothermal Reservoir Site Evaluation in Arizona. Quarterly Progress Report, August 1, 1977--October 31, 1977 Author: Hahman, W.R. Sr. Year: 1977 Progress in the development of a cost-effective exploration program for low- to moderate-temperature geothermal resources is reported. 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 a geothermal energy resource map of Arizona has commenced. Geological field work was directed towards obtaining a broad overview of Arizona geology and regional reconnaissance in the Springerville - St. Johns area. All outside projects are on schedule and the Landsat lineament map and report have been completed Title: Low-Temperature Geothermal Reservoir Site Evaluation in Arizona. Quarterly Progress Report, August 1, 1977--October 31, 1977 Author: Hahman, W.R. Sr. Year: 1977 Progress in the development of a cost-effective exploration program for low- to moderate-temperature geothermal resources is reported. 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 a geothermal energy resource map of Arizona has commenced. Geological field work was directed towards obtaining a broad overview of Arizona geology and regional reconnaissance in the Springerville - St. Johns area. All outside projects are on schedule and the Landsat lineament map and report have been completed Close

• 6. [Image] Evaluation and Targeting of Geothermal Energy Resources in the Southeastern United States. Progress Report, May 1, 1976--October 31, 1976

  	Progress is reported in the development of procedures for the evaluation of low-temperature radiogenically-derived geothermal resources in the eastern United States utilizing geological geochemical, and ...
  	Citation × Citation Citation Abstract Copy Title: Evaluation and Targeting of Geothermal Energy Resources in the Southeastern United States. Progress Report, May 1, 1976--October 31, 1976 Author: Costain, J.K. Year: 1976 Progress is reported in the development of procedures for the evaluation of low-temperature radiogenically-derived geothermal resources in the eastern United States utilizing geological geochemical, and geophysical data. An optimum site for geothermal development in the tectonically stable eastern United States will probably be associated with crustal igneous rocks containing relatively high concentrations of radiogenic heat-producing elements buried beneath an insulating blanket of sediments of low thermal conductivity. Evaluation of plutonic rocks exposed in the Piedmont will aid in the interpretation of gravity and magnetic data for the Atlantic Coastal Plain. Initial results of determination of heat generation from surface samples in South Caroline are encouraging, especially if granitic igneous rocks of similar heat generation can be found beneath sedimentary insulation. Continues logging of existing wells in Coastal Plain sediments supports earlier conclusion that these sediments do behave as efficient sedimentary insulators. Higher temperatures appear to be reached at shallower depths for wells drilled in Coastal Plain sediments in the vicinity of the Georgetown, South Carolina gravity law. Detailed structural mapping in the vicinity of the warm springs in northwestern Virginia has confirmed structural control of the warm springs, and has revealed the existence of kink bands. The kink bands could be related to the development of zones of vertical permeability which serve as conduits in sedimentary rocks for ascending hot water. Title: Evaluation and Targeting of Geothermal Energy Resources in the Southeastern United States. Progress Report, May 1, 1976--October 31, 1976 Author: Costain, J.K. Year: 1976 Progress is reported in the development of procedures for the evaluation of low-temperature radiogenically-derived geothermal resources in the eastern United States utilizing geological geochemical, and geophysical data. An optimum site for geothermal development in the tectonically stable eastern United States will probably be associated with crustal igneous rocks containing relatively high concentrations of radiogenic heat-producing elements buried beneath an insulating blanket of sediments of low thermal conductivity. Evaluation of plutonic rocks exposed in the Piedmont will aid in the interpretation of gravity and magnetic data for the Atlantic Coastal Plain. Initial results of determination of heat generation from surface samples in South Caroline are encouraging, especially if granitic igneous rocks of similar heat generation can be found beneath sedimentary insulation. Continues logging of existing wells in Coastal Plain sediments supports earlier conclusion that these sediments do behave as efficient sedimentary insulators. Higher temperatures appear to be reached at shallower depths for wells drilled in Coastal Plain sediments in the vicinity of the Georgetown, South Carolina gravity law. Detailed structural mapping in the vicinity of the warm springs in northwestern Virginia has confirmed structural control of the warm springs, and has revealed the existence of kink bands. The kink bands could be related to the development of zones of vertical permeability which serve as conduits in sedimentary rocks for ascending hot water. 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

  	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

• 8. [Image] Geothermal Resources, Wilcox Group, Texas Gulf Coast

  	This regional study of the sandstone distribution in the Wilcox Group is part of much broader investigation aimed at assessing the potential for the production of geothermal energy from the geopressured ...
  	Citation × Citation Citation Abstract Copy Title: Geothermal Resources, Wilcox Group, Texas Gulf Coast Author: Bebout, D. G. Year: 1978 This regional study of the sandstone distribution in the Wilcox Group is part of much broader investigation aimed at assessing the potential for the production of geothermal energy from the geopressured zone of the onshore tertiary along the Texas Gulf Coast (Dorfman and Deller, 1975, 1976). The objective of the study is to identify areas where the Wilcox Group contains significant thicknesses of sandstone with subsurface fluid temperatures higher than 300°F. These favorable areas are termed geothermal fairways and are areas in which additional, more detailed work is recommended in the search for prospective geopressured geothermal test-well sites. Reports summarizing similar studies of regional assessment of the Frio Formation and a prospective test-well site have been published by the Bureau of Economic Geology (Bebout, Dorfman, and Agagu, 1975; Bebout, Agagu, and Dorfman, 1975; Bebout, Loucks, Bosch, and Dorfman, 1976; Bebout, Loucks, and Gregory, 1977). The geothermal potential of the Vicksburg Formation is summarized by Loucks (1978). Funding for the entire geopressured geothermal assessment program has been provided by the Division of Geothermal Energy, U. S. Department of Energy Title: Geothermal Resources, Wilcox Group, Texas Gulf Coast Author: Bebout, D. G. Year: 1978 This regional study of the sandstone distribution in the Wilcox Group is part of much broader investigation aimed at assessing the potential for the production of geothermal energy from the geopressured zone of the onshore tertiary along the Texas Gulf Coast (Dorfman and Deller, 1975, 1976). The objective of the study is to identify areas where the Wilcox Group contains significant thicknesses of sandstone with subsurface fluid temperatures higher than 300°F. These favorable areas are termed geothermal fairways and are areas in which additional, more detailed work is recommended in the search for prospective geopressured geothermal test-well sites. Reports summarizing similar studies of regional assessment of the Frio Formation and a prospective test-well site have been published by the Bureau of Economic Geology (Bebout, Dorfman, and Agagu, 1975; Bebout, Agagu, and Dorfman, 1975; Bebout, Loucks, Bosch, and Dorfman, 1976; Bebout, Loucks, and Gregory, 1977). The geothermal potential of the Vicksburg Formation is summarized by Loucks (1978). Funding for the entire geopressured geothermal assessment program has been provided by the Division of Geothermal Energy, U. S. Department of Energy Close