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 The Volcano Hazards Program is a program directed by the USGS that monitors the activity of volcanoes and the public awareness of eruptions. Under the mandate of the Robert T. Stafford Disaster Relief and Emergency Assistance Act (Stafford Act), the ...

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 fede ...

. 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 The Mono–Inyo Craters are a volcanic chain of craters, domes and lava flows in Mono County, Eastern California. The chain stretches from the northwest shore of Mono Lake to the south of Mammoth Mountain. The Mono Lake Volcanic Field forms t ...

. 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 so ...

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 The David A. Johnston Cascades Volcano Observatory (CVO) is a volcano observatory in the US that monitors volcanoes in the northern Cascade Range. It was established in the summer of 1980, after the eruption of Mount St. Helens. 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 Cascade ...

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 Vol ...

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 Ca ...

Mono Craters - Northwest Coulee from CA 120

These were ranked "high threat potential": * Mono-Inyo Craters in eastern California *

Clear Lake Volcanic Field The Clear Lake Volcanic Field is a volcanic field beside Clear Lake in California's northern Coast Ranges. The site of late-Pliocene to early Holocene activity, the volcanic field consists of lava domes, cinder cones, and maars with eruptive pro ...

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 Medicine Lake Volcano is a large shield volcano in northeastern California about northeast of Mount Shasta. The volcano is located in a zone of east-west crustal extension east of the main axis of the Cascade Volcanic Arc and the Cascade Ran ...

in far-northern California, northeast of Mt Shasta *

Salton Buttes The Salton Buttes are a group of volcanoes in California, on the Salton Sea. They consist of a -long row of five lava domes, named Mullet Island, North Red Hill, Obsidian Butte, Rock Hill and South Red Hill. They are closely associated with a f ...

in far-

southern California Southern California (commonly shortened to SoCal) is a geographic and 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 populous urban ...

, 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 Gu ...

These were ranked "moderate threat potential": * Mono Lake Volcanic Field in eastern California *

Coso Volcanic Field The Coso Volcanic Field is located in Inyo County, California, at the western edge of the Basin and Range geologic province and northern region of the Mojave Desert. The Fossil Falls are part of the Coso Field, created by the prehistoric Owens ...

in eastern California *

Soda Lakes The Soda Lakes are two lakes located northwest of Fallon, Nevada. They occupy two basaltic maar volcano craters which may have erupted in the last 1500 years. The larger lake, called Soda Lake or Big Soda Lake, is somewhat elongated, stretching i ...

in northwestern Nevada near Fallon *

in eastern California *

Ubehebe Craters The Ubehebe Craters are a volcanic field in the northern Death Valley of California, consisting of 14–16 craters in a area. The largest of the craters is the wide and deep Ubehebe Crater. Many of the craters, though, are partially buried ...

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 Eure ...

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

See also

References

External links