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• 1. [Image] Geothermal exploration assessment and interpretation, Klamath Basin, Oregon: Swan Lake and Klamath Hills area

  	A synthesis and preliminary interpretation of predominantly geophysical information relating to the Klamath Basin geothermal resource is presented. The Swan Lake Valley area, northeast of Klamath Falls, ...
  	Citation × Citation Citation Abstract Copy Title: Geothermal exploration assessment and interpretation, Klamath Basin, Oregon: Swan Lake and Klamath Hills area Author: Stark, M. Year: 1979 A synthesis and preliminary interpretation of predominantly geophysical information relating to the Klamath Basin geothermal resource is presented. The Swan Lake Valley area, northeast of Klamath Falls, and the Klamath Hills area, south of Klamath Falls, are discussed in detail. Available geophysical data, including gravity, magnetic, electrical resistivity, microearthquake, roving dipole resistivity, audio-magnetotelluric (AMT) and magnetotelluric (MT) data sets, are examined and reinterpreted for these areas. One- and two-dimensional modeling techniques are applied, and general agreement among overlapping data sets is achieved. The MT method appears well suited to this type of exploration, although interpretation is difficult in the complex geology. Roving dipole and AMT are useful in reconnaissance, while gravity and magnetics help in defining structure. For the Swan Lake Valley the data suggest buried electrically conductive zones beneath Meadow Lake Valley and Swan Lake, connected by a conductive layer at 1 kilometer depth. In the Klamath Hills area, the data suggest a conductive zone centered near the northwestern tip of Stukel Mountain, associated with a concealed northeast-trending cross-fault. Another conductive zone appears near some producing hot wells at the southwestern edge of the Klamath Hills. These conductive zones may represent geothermal reservoirs. Follow-up work is recommended for each target area; LBL-8186 Title: Geothermal exploration assessment and interpretation, Klamath Basin, Oregon: Swan Lake and Klamath Hills area Author: Stark, M. Year: 1979 A synthesis and preliminary interpretation of predominantly geophysical information relating to the Klamath Basin geothermal resource is presented. The Swan Lake Valley area, northeast of Klamath Falls, and the Klamath Hills area, south of Klamath Falls, are discussed in detail. Available geophysical data, including gravity, magnetic, electrical resistivity, microearthquake, roving dipole resistivity, audio-magnetotelluric (AMT) and magnetotelluric (MT) data sets, are examined and reinterpreted for these areas. One- and two-dimensional modeling techniques are applied, and general agreement among overlapping data sets is achieved. The MT method appears well suited to this type of exploration, although interpretation is difficult in the complex geology. Roving dipole and AMT are useful in reconnaissance, while gravity and magnetics help in defining structure. For the Swan Lake Valley the data suggest buried electrically conductive zones beneath Meadow Lake Valley and Swan Lake, connected by a conductive layer at 1 kilometer depth. In the Klamath Hills area, the data suggest a conductive zone centered near the northwestern tip of Stukel Mountain, associated with a concealed northeast-trending cross-fault. Another conductive zone appears near some producing hot wells at the southwestern edge of the Klamath Hills. These conductive zones may represent geothermal reservoirs. Follow-up work is recommended for each target area; LBL-8186 Close

• 2. [Image] Geology of the Cove Fort-Sulphurdale KGRA

  	The Cove Fort-Sulphurdale Known Geothermal Resource Area (KGRA) is located on the northwestern margin of the Marysvale volcanic field in southwestern Utah. The geology of the KGRA is dominated by lava ...
  	Citation × Citation Citation Abstract Copy Title: Geology of the Cove Fort-Sulphurdale KGRA Author: Moore, J.N. Year: 1979 The Cove Fort-Sulphurdale Known Geothermal Resource Area (KGRA) is located on the northwestern margin of the Marysvale volcanic field in southwestern Utah. The geology of the KGRA is dominated by lava flows and ash-flow tuffs of late Oligocene to mid-Miocene age that were deposited on faulted sedimentary rocks of Paleozoic to Mesozoic age. The geothermal system of the Cove Fort-Sulphurdale KGRA is structurally controlled by normal faults. High-angle faults control fluid flow within the geothermal reservoir, while the gravitational glide blocks provide an impermeable cap for the geothermal system in the central part of the field. Surficial activity occurring to the north and south of the glide blocks is characterized by the evolution of hydrogen sulfide and deposition of native sulphur. Intense acid alteration of the aluvium, resulting from downward migration of sulphuric acid, has left porous siliceous residues that retain many of the original sedimentary structures. Detailed logs of Union Oil Company drill holes Forminco No. 1, Utah State 42-7, and Utah State 31-33 are included Title: Geology of the Cove Fort-Sulphurdale KGRA Author: Moore, J.N. Year: 1979 The Cove Fort-Sulphurdale Known Geothermal Resource Area (KGRA) is located on the northwestern margin of the Marysvale volcanic field in southwestern Utah. The geology of the KGRA is dominated by lava flows and ash-flow tuffs of late Oligocene to mid-Miocene age that were deposited on faulted sedimentary rocks of Paleozoic to Mesozoic age. The geothermal system of the Cove Fort-Sulphurdale KGRA is structurally controlled by normal faults. High-angle faults control fluid flow within the geothermal reservoir, while the gravitational glide blocks provide an impermeable cap for the geothermal system in the central part of the field. Surficial activity occurring to the north and south of the glide blocks is characterized by the evolution of hydrogen sulfide and deposition of native sulphur. Intense acid alteration of the aluvium, resulting from downward migration of sulphuric acid, has left porous siliceous residues that retain many of the original sedimentary structures. Detailed logs of Union Oil Company drill holes Forminco No. 1, Utah State 42-7, and Utah State 31-33 are included Close

• 3. [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