CALIFORNIA VOLCANO OBSERVATORY MONTHLY UPDATE

U.S. Geological Survey

Monday, November 2, 2015 12:31 PM PST (Monday, November 2, 2015 20:31 UTC)



Monitored CALIFORNIA VOLCANOES
Current Volcano Alert Level: all NORMAL
Current Aviation Color Code: all GREEN

Activity Update: 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.


Observations for October 1, 2015 (0000h PST) through October 31, 2015 (2359h PDT):
Mt Shasta: Two M1 or greater earthquakes were detected. The largest event registered M1.86.
Medicine Lake: One M1 or greater earthquake was detected (M1.22).
Lassen Volcanic Center: One earthquake of M1.0 or greater was detected (M1.19).
Clear Lake Volcanic Field: Three earthquakes of M1.0 or greater were detected. The largest event registered M1.67. [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 M3.30].
Long Valley Volcanic Region: In Long Valley Caldera, 10 earthquakes of M1.0 or greater were detected. The largest event registered M1.79. In the Mono Craters region, 1 earthquake of M1.0 or greater was detected (M1.44). No earthquakes of M1.0 or greater 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 M2.35].
Ubehebe Craters: No earthquakes at or above M1.0 were detected.
Salton Buttes: Six earthquakes of M1.0 or greater were detected. The largest registered M1.79.
Coso Volcanic Field: The typical high level of seismicity was observed, with 12 earthquakes M1.0 or greater. The largest registered M2.05.

The U.S. Geological Survey will continue to monitor these volcanoes closely and will issue additional updates and changes in alert level as warranted. For a definition of alert levels see http://volcanoes.usgs.gov/activity/alertsystem/icons.php.

As 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. For additional USGS CalVO volcano information, background, images, and other graphics visit http://volcanoes.usgs.gov/observatories/calvo/. For general information on the USGS Volcano Hazard Program http://volcanoes.usgs.gov. Statewide seismic information for California and Nevada can be found at http://earthquake.usgs.gov/earthquakes/recenteqscanv/.

Links for Other Volcano Observatories

US Volcanoes and Current Activity Alerts
USGS Cascades Volcano Observatory
Volcano Observatories: Alaska
Volcano Observatories: Cascades
Volcano Observatories: Hawaii
Volcano Observatories: Long Valley
Volcano Observatories: Mariana Islands
Volcano Observatories: Yellowstone