The California Volcano Observatory (CalVO) is the volcano observatory that monitors the volcanic and geologic activity of California and Nevada. It is a part of the Volcano Hazards Program of the

United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...

, a scientific agency of the

United States government The federal government of the United States (U.S. federal government or U.S. government) is the national government of the United States, a federal republic located primarily in North America, composed of 50 states, a city within a f ...

. Originally, the volcano observatory was known as the Long Valley Observatory which monitored volcanic activity east of the

Sierra Nevada The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...

Mono County, California Mono County ( ) is a county located in the east central portion of the U.S. state of California. As of the 2020 census, the population was 13,195, making it the fourth-least populous county in California. The county seat is Bridgeport. The co ...

which included

Long Valley Caldera Long Valley Caldera is a depression in eastern California that is adjacent to Mammoth Mountain. The valley is one of the Earth's largest calderas, measuring about long (east-west), wide (north-south), and up to deep. Long Valley was formed 7 ...

Mammoth Mountain Mammoth Mountain is a lava dome complex partially located within the town of Mammoth Lakes, California, in the Inyo National Forest of Madera and Mono Counties. It is home to a large ski area primarily on the Mono County side. Mammoth Mounta ...

, and the Mono–Inyo Craters. In 2012, the Long Valley Observatory was integrated into the new California Volcano Observatory based in

Menlo Park, California Menlo Park is a city at the eastern edge of San Mateo County within the San Francisco Bay Area of California in the United States. It is bordered by San Francisco Bay on the north and east; East Palo Alto, Palo Alto, and Stanford to the sou ...

which covers the entire states of California and Nevada, this includes the southern Cascade Range volcanoes in the state of California which were previously under the jurisdiction of the Cascades Volcano Observatory.

Monitored volcanoes

These are the volcanoes monitored by the California Volcano Observatory, in order of highest to lowest risk assessment. Mount Shasta from I-5

According to USGS risk assessment of the volcanoes in CalVO's region, the following volcanoes were ranked "very high threat potential". *

Mount Shasta Mount Shasta ( Shasta: ''Waka-nunee-Tuki-wuki''; Karuk: ''Úytaahkoo'') is a potentially active volcano at the southern end of the Cascade Range in Siskiyou County, California. At an elevation of , it is the second-highest peak in the Cascades ...

in far-

northern California Northern California (colloquially known as NorCal) is a geographic and cultural region that generally comprises the northern portion of the U.S. state of California. Spanning the state's northernmost 48 counties, its main population centers incl ...

, north of Redding * Lassen Volcanic Center in

Lassen Volcanic National Park Lassen Volcanic National Park is an American national park in northeastern California. The dominant feature of the park is Lassen Peak, the largest plug dome volcano in the world and the southernmost volcano in the Cascade Range. Lassen Volc ...

eastern California Eastern California is a region defined as either the strip to the east of the crest of the Sierra Nevada or as the easternmost counties of California. Demographics According to the 2010 census, the population of the eastern border counties of ...

Mono Craters - Northwest Coulee from CA 120

These were ranked "high threat potential": * Mono-Inyo Craters in eastern California * Clear Lake Volcanic Field north of the

San Francisco Bay Area The San Francisco Bay Area, often referred to as simply the Bay Area, is a populous region surrounding the San Francisco, San Pablo, and Suisun Bay estuaries in Northern California. The Bay Area is defined by the Association of Bay Area Gov ...

* Medicine Lake Volcano in far-northern California, northeast of Mt Shasta * Salton Buttes in far-

southern California Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural region that generally comprises the southern portion of the U.S. state of California. It includes the Los Angeles metropolitan area, the second most po ...

, at the

Salton Sea The Salton Sea is a shallow, landlocked, highly saline body of water in Riverside and Imperial counties at the southern end of the U.S. state of California. It lies on the San Andreas Fault within the Salton Trough that stretches to the Gul ...

These were ranked "moderate threat potential": * Mono Lake Volcanic Field in eastern California * Coso Volcanic Field in eastern California * Soda Lakes in northwestern Nevada near Fallon *

in eastern California * Ubehebe Craters in

Death Valley National Park Death Valley National Park is an American national park that straddles the California–Nevada border, east of the Sierra Nevada. The park boundaries include Death Valley, the northern section of Panamint Valley, the southern section of Eurek ...

One was ranked "Low to Very Low Threat Potential": * Golden Trout Creek volcanic field in Sequoia National Forest.USGS Volcanic Hazards Program
/ref> Other volcanoes in the region have not been assessed at one of these risk levels that warrant monitoring. Volcanoes which have not erupted during the

Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togeth ...

were not included. USGS noted that though less probable it is still possible for volcanoes to erupt on longer intervals than that. Map of Long Valley Mono area

References

External links

* 2012 establishments in California Earth sciences Government agencies established in 2012 Volcano observatories Volcanism of California Volcanism of Nevada United States Geological Survey Buildings and structures in Mono County, California Inyo National Forest Sierra Nevada (United States) {{US-geology-stub

Monitored volcanoes

See also

References

External links