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Locations of earthquakes of at least magnitude 1.0 in 2025 and the outlines of the boxes CalVO uses to count earthquakes around Long Valley. Only 6 earthquakes were located inside the Long Valley Caldera box. (Earthquake location data from Northern California Seismic Network.) Figure by Alicia Hotovec-Ellis, USGS.
Locations of earthquakes of at least magnitude 1.0 in 2025 and the outlines of the boxes CalVO uses to count earthquakes around Long Valley. Only 6 earthquakes were located inside the Long Valley Caldera box. (Earthquake location data from Northern California Seismic Network.) Figure by Alicia Hotovec-Ellis, USGS.
Graphs of the number of earthquakes located each year since 1980 in the Long Valley Caldera and nearby Sierra Block monitoring boxes. Note that the number of earthquakes on the left shown on a logarithmic scale, which means they increase an order of magnitude with each "step." Figure by Alicia Hotovec-Ellis, USGS.
Graphs of the number of earthquakes located each year since 1980 in the Long Valley Caldera and nearby Sierra Block monitoring boxes. Note that the number of earthquakes on the left shown on a logarithmic scale, which means they increase an order of magnitude with each "step." Figure by Alicia Hotovec-Ellis, USGS.
This seismic station in the Lassen Volcanic Center was damaged during the Dixie Fire of 2021, which burned huge swathes of forest in the Lassen Volcanic National Park. Above-ground equipment, including the tree that held the antenna and solar panel above winter snows, was destroyed; belowground seismic sensors were recoverable. USGS photo by Ryan Presser, NCSN.
This seismic station in the Lassen Volcanic Center was damaged during the Dixie Fire of 2021, which burned huge swathes of forest in the Lassen Volcanic National Park. Above-ground equipment, including the tree that held the antenna and solar panel above winter snows, was destroyed; belowground seismic sensors were recoverable. USGS photo by Ryan Presser, NCSN.
The cryogenic magnetometer within the shielded room in the U.S. Geological Survey Paleomagnetics Laboratory. Major features of the cryogenic magnetometer are labeled. Picture by A. Pivarunas (U.S. Geological Survey)
The cryogenic magnetometer within the shielded room in the U.S. Geological Survey Paleomagnetics Laboratory. Major features of the cryogenic magnetometer are labeled. Picture by A. Pivarunas (U.S. Geological Survey)
The California Volcano Observatory was created in 2012. Its logo shows Mount Shasta with a California grizzly bear (extinct) in the foreground.
The California Volcano Observatory was created in 2012. Its logo shows Mount Shasta with a California grizzly bear (extinct) in the foreground.
Roughly a third of the total erupted volume of the Clear Lake volcanic field is represented by the ~ 35 km3 of rocks comprising Mt. Konocti and nearby hills. The mountain itself is over 1200 m (~4000 ft) high and is comprised primarily of a series of dacitic lava domes – Buckingham Peak, Wright Peak, and South Peak, and Howard Peak are all dacites.
Roughly a third of the total erupted volume of the Clear Lake volcanic field is represented by the ~ 35 km3 of rocks comprising Mt. Konocti and nearby hills. The mountain itself is over 1200 m (~4000 ft) high and is comprised primarily of a series of dacitic lava domes – Buckingham Peak, Wright Peak, and South Peak, and Howard Peak are all dacites.