All volcanoes monitored by CalVO using telemetered, real-time sensor networks exhibit normal levels of background seismicity and deformation.
Volcanoes monitored include Mount Shasta, Medicine Lake Volcano, Clear Lake Volcanic Field, Lassen Volcanic Center, Long Valley Volcanic Region, Coso Volcanic Field, Ubehebe Craters, and Salton Buttes.
Good News, the volcanic activity in California will not blow away any dams or trigger evacuations! The volcanic activity is all on the GREEN side.
Between January 1, 2017 (0000h PST) through January 31, 2017 (2359h PDT):
Mt Shasta: No earthquakes at or above M1.0 were detected.
Medicine Lake: No earthquakes at or above M1.0 were detected.
Lassen Volcanic Center: Eight earthquakes at or above M1.0 were detected. The largest event registered M2.12.
Clear Lake Volcanic Field: Five earthquakes at or above M1.0 were detected, with the largest registering M2.26. [Note: The typical high level of seismicity was observed under the Geysers steam field located at the western margin of CLVF. The largest event was M3.89].
Long Valley Volcanic Region: In Long Valley Caldera, 46 earthquakes of M1.0 or greater were detected, with the largest event registering M2.12. Four earthquakes at or above M1.0 were detected in the Mono Craters region, with the largest registering M2.08. No earthquakes at or above M1.0 were detected under Mammoth Mountain. [Note: The typical high level of seismicity was observed south of the caldera in the Sierra Nevada range. The largest event registered M3.44].
Ubehebe Craters: No earthquakes at or above M1.0 were detected.
Salton Buttes: Six earthquakes of M1.0 or greater were detected, with the largest registering M1.96
Coso Volcanic Field: The typical high level of seismicity was observed, with 28 earthquakes M1.0 or greater. The largest registered M2.67.
Meanwhile, a significant explosive eruption began at Bogoslof volcano at about 16:24 UTC on February 13 (07:24 AKST on February 13) as indicated in seismic data. Although at this time there has been no lightning detected, nor satellite images received to confirm eruptive activity, the intensity of seismicity strongly suggests that significant ash emissions have occurred. Thus, AVO is raising the Aviation Color Code to RED and Alert level to WARNING.
The U.S. Geological Survey will continue to monitor these volcanoes closely and will issue additional updates and changes in alert level as warranted. Get prepared in any cases!