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• 1. [Image] Dipole-Dipole Resistivity Survey of a Portion of the Coso Hot Springs KGRA, Inyo County, California

  	A detailed electrical resistivity survey of 54 line-km was completed at the Coso Hot Springs KGRA in September 1977. This survey has defined a bedrock resistivity low at least 4 sq mi (10 sq km) in extent ...
  	Citation × Citation Citation Abstract Copy Title: Dipole-Dipole Resistivity Survey of a Portion of the Coso Hot Springs KGRA, Inyo County, California Author: Fox, R.C. Year: 1978 A detailed electrical resistivity survey of 54 line-km was completed at the Coso Hot Springs KGRA in September 1977. This survey has defined a bedrock resistivity low at least 4 sq mi (10 sq km) in extent associated with the geothermal system at Coso. The boundaries of this low are generally well defined to the north and west but not as well to the south where an approximate southern limit has been determined. The bedrock resistivity low merges with an observed resistivity low over gravel fill east of Coso Hot Springs. A complex horizontal and vertical resistivity structure of the surveyed area has been defined which precludes the use of layered-earth or two-dimensional interpretive models for much of the surveyed area. In general the survey data indicate that a 10 to 20 ohm-meter zone extends from near surface to a depth greater than 750 meters within the geothermal system. This zone is bordered to the north and west by bedrock resistivities greater than 200 ohm-meters and to the south by bedrock resistivities greater than 50 ohm-meters. A combination of observed increases in: (1) fracture density (higher permeability), (2) alteration (high clay content), and (3) temperatures (higher dissolved solid content of ground water) within the bedrock low explain its presence Title: Dipole-Dipole Resistivity Survey of a Portion of the Coso Hot Springs KGRA, Inyo County, California Author: Fox, R.C. Year: 1978 A detailed electrical resistivity survey of 54 line-km was completed at the Coso Hot Springs KGRA in September 1977. This survey has defined a bedrock resistivity low at least 4 sq mi (10 sq km) in extent associated with the geothermal system at Coso. The boundaries of this low are generally well defined to the north and west but not as well to the south where an approximate southern limit has been determined. The bedrock resistivity low merges with an observed resistivity low over gravel fill east of Coso Hot Springs. A complex horizontal and vertical resistivity structure of the surveyed area has been defined which precludes the use of layered-earth or two-dimensional interpretive models for much of the surveyed area. In general the survey data indicate that a 10 to 20 ohm-meter zone extends from near surface to a depth greater than 750 meters within the geothermal system. This zone is bordered to the north and west by bedrock resistivities greater than 200 ohm-meters and to the south by bedrock resistivities greater than 50 ohm-meters. A combination of observed increases in: (1) fracture density (higher permeability), (2) alteration (high clay content), and (3) temperatures (higher dissolved solid content of ground water) within the bedrock low explain its presence Close

• 2. [Image] Low -Altitude Aeromagnetic Survey of a Portion of the Coso Hot Springs KGRA, Inyo County, California

  	A detailed low-altitude aeromagnetic survey of 576 line-mi (927 line-km) was completed over a portion of the Coso Hot Springs KGRA in September 1977. The survey has defined a pronounced magnetic low that ...
  	Citation × Citation Citation Abstract Copy Title: Low -Altitude Aeromagnetic Survey of a Portion of the Coso Hot Springs KGRA, Inyo County, California Author: Fox, R.C. Year: 1978 A detailed low-altitude aeromagnetic survey of 576 line-mi (927 line-km) was completed over a portion of the Coso Hot Springs KGRA in September 1977. The survey has defined a pronounced magnetic low that could help delineate the geothermal system. The magnetic low has an areal extent of approximately 10 C' sq mi (26 sq km). Direct and indirect evidence indicates that this anomaly is due, in part, to magnetite destruction by hydrothermal solutions associated with the geothermal system. The anomaly generally coincides with two other geophysical anomalies which are directly associated with the system: 1) a bedrock electrical resistivity low, and 2) an area of relatively high near-surface temperatures. The highest measured heat flow, 18 HFU, also occurs within its boundary. The magnetic low occurs at the intersection of two major structural zones which coincide with a complementary set of strike-slip fault zones determined from seismic activity. The intersection of these two zones of active tectonism probably served as the locus for emplacement of a pluton at depth, above which are observed the coincidental geophysical anomalies and surface manifestations related to the geothermal system Title: Low -Altitude Aeromagnetic Survey of a Portion of the Coso Hot Springs KGRA, Inyo County, California Author: Fox, R.C. Year: 1978 A detailed low-altitude aeromagnetic survey of 576 line-mi (927 line-km) was completed over a portion of the Coso Hot Springs KGRA in September 1977. The survey has defined a pronounced magnetic low that could help delineate the geothermal system. The magnetic low has an areal extent of approximately 10 C' sq mi (26 sq km). Direct and indirect evidence indicates that this anomaly is due, in part, to magnetite destruction by hydrothermal solutions associated with the geothermal system. The anomaly generally coincides with two other geophysical anomalies which are directly associated with the system: 1) a bedrock electrical resistivity low, and 2) an area of relatively high near-surface temperatures. The highest measured heat flow, 18 HFU, also occurs within its boundary. The magnetic low occurs at the intersection of two major structural zones which coincide with a complementary set of strike-slip fault zones determined from seismic activity. The intersection of these two zones of active tectonism probably served as the locus for emplacement of a pluton at depth, above which are observed the coincidental geophysical anomalies and surface manifestations related to the geothermal system Close