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Coso Volcanic Field

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The Coso volcanic field is located about 160 km (100 mi) northeast of Bakersfield, California, mainly within the boundary of the Naval Air Weapons Station, China Lake. It covers approximately 400 square kilometers (roughly 150 square miles) and is home to one of the largest producers of geothermal power in the U.S., with an output sufficient to supply the needs of 270,000 homes.

Quick Facts

Location: California, Inyo County

Latitude: 36.03° N

Longitude: 117.82° W

Elevation: 2,400 (m) 7,874 (f)

Volcano type: monogenetic volcanic field

Composition: basalt to rhyolite

Most recent eruption: 40,000 years ago

Nearby towns: Olancha, Pearsonville

Threat Potential: Moderate*

*based on the National Volcano Early Warning System

Summary

The Coso volcanic field geothermal resource fuels the many hot springs, steam vents, and boiling mud pots near the center of the Coso Volcanic Field. About 40 eruptions in the last quarter million years produced a field of steep-sided lava domes, red hills of volcanic cinder, and rough-surfaced lava flows. The most recent eruption occurred about 40,000 years ago forming the Volcano Peak basaltic cinder cone and lava flow. Some geological landform relationships suggest that the youngest lava dome may have formed within the past 12,000 years, but this young activity has not been confirmed via dating methods. Geophysical and geochemical studies detect a zone of partially molten rock (magma) underlying the center of the Coso Volcanic Field. Small to moderate earthquakes, some due to the geothermal resource are common. The U.S. Navy monitors earthquake and geothermal activity within the Coso Volcanic Field.

News

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Having a (volcanic) field day in California

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One benefit of California’s volcanoes? Geothermal energy

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Unpacking CalVO's new seismic monitoring boxes

Publications

California’s exposure to volcanic hazards

The potential for damaging earthquakes, landslides, floods, tsunamis, and wildfires is widely recognized in California. The same cannot be said for volcanic eruptions, despite the fact that they occur in the state about as frequently as the largest earthquakes on the San Andreas Fault. At least ten eruptions have taken place in the past 1,000 years, and future volcanic eruptions are inevitable.The

Authors
Margaret Mangan, Jessica Ball, Nathan Wood, Jamie L. Jones, Jeff Peters, Nina Abdollahian, Laura Dinitz, Sharon Blankenheim, Johanna Fenton, Cynthia Pridmore

2018 update to the U.S. Geological Survey national volcanic threat assessment

When erupting, all volcanoes pose a degree of risk to people and infrastructure, however, the risks are not equivalent from one volcano to another because of differences in eruptive style and geographic location. Assessing the relative threats posed by U.S. volcanoes identifies which volcanoes warrant the greatest risk-mitigation efforts by the U.S. Geological Survey and its partners. This update

Authors
John W. Ewert, Angela K. Diefenbach, David W. Ramsey

The California Volcano Observatory: Monitoring the state's restless volcanoes

Volcanic eruptions happen in the State of California about as frequently as the largest earthquakes on the San Andreas Fault Zone. At least 10 eruptions have taken place in California in the past 1,000 years—most recently at Lassen Peak in Lassen Volcanic National Park (1914 to 1917) in the northern part of the State—and future volcanic eruptions are inevitable. The U.S. Geological Survey Californ

Authors
Wendy K. Stovall, Mae Marcaida, Margaret T. Mangan

Science

Deformation monitoring at Coso Volcanic Field

There are currently three GPS receivers that make up the continuous deformation monitoring network at Coso volcanic field.
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Deformation monitoring at Coso Volcanic Field

There are currently three GPS receivers that make up the continuous deformation monitoring network at Coso volcanic field.
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Seismic monitoring at Coso volcanic field

There is currently one USGS operated seismometer near Coso volcanic field, which was installed in 2001. Monitoring conducted by the U.S. Navy suggests there are common small to moderate earthquakes associated with the geothermal resource.
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Seismic monitoring at Coso volcanic field

There is currently one USGS operated seismometer near Coso volcanic field, which was installed in 2001. Monitoring conducted by the U.S. Navy suggests there are common small to moderate earthquakes associated with the geothermal resource.
Learn More

Hazards Summary for Coso Volcanic Field

Although the youngest eruption was dated at about 40,000 years the robust geothermal system and evidence of a magma reservoir underneath Coso Volcanic Field suggests that future eruptions are likely.
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Hazards Summary for Coso Volcanic Field

Although the youngest eruption was dated at about 40,000 years the robust geothermal system and evidence of a magma reservoir underneath Coso Volcanic Field suggests that future eruptions are likely.
Learn More