California Volcano Observatory

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As a part of the U.S. Geological Survey's Volcano Hazards Program, the California Volcano Observatory aims to advance scientific understanding of volcanic processes and lessen the harmful impacts of volcanic activity in the volcanically active areas of California and Nevada. 


News

Date published: July 10, 2019

Earthquake swarm south of Coso Volcanic Field continues with declining intensity. We continue to monitor

The seismic activity that started on the evening of July 5 at the southern margin of Coso Volcanic Field in Inyo County, California continues at a rate of about 600 M1.0 or greater earthquakes per day.

Date published: July 6, 2019

Earthquake swarm south of Coso Volcanic Field related to tectonic, not volcanic, activity. We continue to monitor.

An earthquake swarm started on the evening of July 5 at the southern margin of Coso Volcanic Field in Inyo County, California.

Date published: May 6, 2019

The National Volcano Early Warning System (NVEWS) will help USGS better monitor nation’s most dangerous volcanoes

In September 2004, USGS scientists detected sudden, but unmistakable, signs that Mount St. Helens was waking up. Volcano monitors had picked up the occurrence of hundreds of small earthquakes and other signals that the volcano’s crater floor had begun to rise. Within a week, several eruptions blasted clouds of ash into the atmosphere, and soon after, a new lava dome emerged in the crater.

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