KONOCTI BAY FAULT ZONE, LAKE COUNTY, CALIFORNIA: A REEVALUATION.

J. Michael Thompson

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KONOCTI BAY FAULT ZONE, LAKE COUNTY, CALIFORNIA: A REEVALUATION.

J. Michael Thompson

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Abstract

The Konocti Bay Fault Zone (KBFZ), initially regarded by some as a promising liquid-dominated hydrothermal system, has been a disappointment as a geothermal prospect. Five exploratory wells have been drilled in the vicinity of the KBFZ, but none of them are producing thermal fluids; in fact, three have been abandoned. This may be because hydrothermal fluid discharges along the KBFZ are low. The Na-K-Ca and Na-Li geothermometers indicate that the waters discharging around Howard and Seigler Springs may have equilibrated at temperatures above 200 degree C. If boiling has occurred or is occurring, a chloride-enthalpy diagram may be appropriate. Such a diagram for the KBFZ shows that a water in excess of 250 degree C existed or may exist in the area. However, because currently measured temperatures rarely exceed 50 degree C and magnesium concentration in the water is high, very little deep high temperature water may be present. Refs.

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J. Michael Thompson. 1984. KONOCTI BAY FAULT ZONE, LAKE COUNTY, CALIFORNIA: A REEVALUATION.. https://pubs.usgs.gov/publication/70014041

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