Geothermal regimes of the Clearlake region, northern California

Technical Report · Mon Jun 01 04:00:00 EDT 1998

DOI:https://doi.org/10.2172/663361· OSTI ID:663361

Amador, M ^[1]; Burns, K L; Potter, R M

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1. ed.

The first commercial production of power from geothermal energy, at The Geysers steamfield in northern California in June 1960, was a triumph for the geothermal exploration industry. Before and since, there has been a search for further sources of commercial geothermal power in The Geysers--Clear Lake geothermal area surrounding The Geysers. As with all exploration programs, these were driven by models. The models in this case were of geothermal regimes, that is, the geometric distribution of temperature and permeability at depth, and estimates of the physical conditions in subsurface fluids. Studies in microseismicity and heat flow, did yield geophysical information relevant to active geothermal systems. Studies in stable-element geochemistry found hiatuses or divides at the Stoney Creek Fault and at the Collayomi Fault. In the region between the two faults, early speculation as to the presence of steamfields was disproved from the geochemical data, and the potential existence of hot-water systems was predicted. Studies in isotope geochemistry found the region was characterized by an isotope mixing trend. The combined geochemical data have negative implications for the existence of extensive hydrothermal systems and imply that fluids of deep origin are confined to small, localized systems adjacent to faults that act as conduits. There are also shallow hot-water aquifers. Outside fault-localized systems and hot-water aquifers, the area is an expanse of impermeable rock. The extraction of energy from the impermeable rock will require the development and application of new methods of reservoir creation and heat extraction such as hot dry rock technology.

• Research Organization: Los Alamos National Lab., NM (United States)
• Sponsoring Organization: USDOE Assistant Secretary for Energy Efficiency and Renewable Energy, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 663361
• Report Number(s): LA--13375-MS; ON: DE98006021
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
EXPERIMENTAL DATA
GEOCHEMISTRY
GEOLOGIC MODELS
GEOTHERMAL EXPLORATION
GEYSERS GEOTHERMAL FIELD
Geothermal Legacy
HEAT FLUX
MICROEARTHQUAKES