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Bi-national Exchange provides opportunity for Chile and US officials to work together on volcano hazard risk reduction

Bi-national Exchange provides opportunity for Chile and US officials to work together on volcano hazard risk reduction

Scientists, civil authorities, and emergency managers from Chile and the U.S. met in California to discuss the challenges of effective volcanic hazard...

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Lassen Peak Eruption 100th Anniversary - May, 2015

Lassen Peak Eruption 100th Anniversary - May, 2015

2015 marks the centennial of the May 22, 1915 explosive eruption of Lassen Peak.

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Mount Shasta earthquake series poses no immediate hazard

Mount Shasta earthquake series poses no immediate hazard

Since February 19, 2015 an ongoing series of small earthquakes has been occurring approximately 5 miles southeast of the summit of Mount Shasta, near...

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Earthquake Swarm near Lassen Volcanic Center

Earthquake Swarm near Lassen Volcanic Center

CalVO is tracking an earthquake swarm that began on November 9 located at the Tehama County-Plumas County border within Lassen National Forest.

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Published overview of low-level unrest in the Long Valley Caldera, eastern California

Published overview of low-level unrest in the Long Valley Caldera, eastern California

A cataclysmic eruption of 600 km3 of rhyolite magma (Bishop Tuff) about 760,000 years ago resulted in the collapse of the partially evacuated magma...

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Sierra Nevada Earthquake Swarm

Sierra Nevada Earthquake Swarm

The USGS California Volcano Observatory (CalVO) is tracking an earthquake swarm in the Sierra Nevada range south of Long Valley Caldera, about 8 miles...

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Earthquake Swarm in Long Valley Caldera Diminishes

Earthquake Swarm in Long Valley Caldera Diminishes

Over the past 42 hours, the earthquake swarm in California's Long Valley Caldera, which began last Friday (see September 26 post), has gradually...

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Earthquake Swarm in Long Valley Caldera

Earthquake Swarm in Long Valley Caldera

We have been closely tracking an earthquake swarm in California's Long Valley Caldera, which started yesterday at around 4AM PDT (September 25, 2014)...

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Mount Shasta debris flow not linked to volcanic activity

Mount Shasta debris flow not linked to volcanic activity

On the afternoon of September 20, a large volume of water surged down Mount Shasta's south flank into Mud Creek, entraining debris and inundating the...

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Automated Volcanic-Gas Sniffer Installed at Mammoth Mountain Fumarole

Automated Volcanic-Gas Sniffer Installed at Mammoth Mountain Fumarole

In July 2014, USGS Scientists Peter Kelly (Cascades Volcano Observatory) and Stuart Wilkinson (California Volcano Observatory) installed an automated...

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Investigating Past Eruptions of Mono Craters

Investigating Past Eruptions of Mono Craters

CalVO geologist Mae Marcaida examines thin layers of volcanic ash sandwiched between thick beds of sediment deposited by ancestral Mono Lake in...

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Small Earthquake Swarm

Small Earthquake Swarm

A swarm of small earthquakes (magnitudes less than 2) occurred at a depth of 6-7 km (about 4 miles) beneath Highway 203 in Mammoth Lakes, California...

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