Thursday, February 9, 2012 9:30 AM PST (Thursday, February 9, 2012 17:30 UTC)
Monitored CALIFORNIA VOLCANOES Current Volcano Alert Level: all NORMAL Current Aviation Color Code: all GREEN
Activity Update: All volcanoes monitored by CalVO's telemetered, real-time sensor networks exhibit normal levels of background seismicity and deformation. Real-time monitoring networks are in place at Mount Shasta, Medicine Lake Volcano, Clear Lake Volcanic Field, Lassen Volcanic Center, Long Valley Caldera and Mono-Inyo Chain.
Observations for January 1, 2012 (00:00 PST) through January 31, 2012 (00:00 PST): Mt Shasta: One M=1.6 earthquake. Medicine Lake: No earthquakes of M=1.0 or greater. Lassen Volcanic Center: No earthquakes of M=1.0 or greater. Clear Lake Volcanic Field: Seven earthquakes (largest M=3.8; all others below 2.0). [Note: Typical high level of seismicity observed under the Geysers steam field located outside the eastern margin of CLVF. Largest event was M=3.1]. Long Valley Caldera and Mono-Inyo Chain: Ten earthquakes occurred in Long Valley Caldera (all with M<2.0); Nine earthquakes east of Mono Lake (all M<2.0); Eight earthquakes under Mammoth Mountain (all M<2.0). [Note: Typical high level of seismicity observed south of the caldera in the Sierra Nevada range. Largest event was M=2.9].
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://volcano.wr.usgs.gov/vsc/observatories/calvo.html. 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/.
LONG VALLEY OBSERVATORY WEEKLY UPDATE
Thursday, January 12, 2012 5:46 PM PST (Friday, January 13, 2012 01:46 UTC)
LONG VALLEY VOLCANIC CENTER VOLCANO (CAVW #1203-14-) 37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m) Current Volcano Alert Level: NORMAL Current Aviation Color Code: GREEN
Fifteen earthquakes with magnitudes between M=1.0 and M=1.8 occurred in the Mammoth Lakes-Long Valley region in the last seven days. The events were located in the Sierra Nevada, with the exception of three earthquakes in the caldera east of the town of Mammoth Lakes and one event in Round Valley.
LONG VALLEY OBSERVATORY WEEKLY UPDATE
Wednesday, January 4, 2012 3:01 PM PST (Wednesday, January 4, 2012 23:01 UTC)
LONG VALLEY VOLCANIC CENTER VOLCANO (CAVW #1203-14-) 37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m) Current Volcano Alert Level: NORMAL Current Aviation Color Code: GREEN
Fifteen earthquakes with magnitudes between M=1.0 and M=3.0 occurred in the Mammoth Lakes-Long Valley region in the last seven days. The events were located in the Sierra Nevada, with the exception of two events in the caldera east of Mammoth Lakes and one event in Round Valley.
LONG VALLEY OBSERVATORY WEEKLY UPDATE
Monday, December 19, 2011 11:25 AM PST (Monday, December 19, 2011 19:25 UTC)
LONG VALLEY VOLCANIC CENTER VOLCANO (CAVW #1203-14-) 37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m) Current Volcano Alert Level: NORMAL Current Aviation Color Code: GREEN
Four earthquakes occurred in the Mammoth Lakes-Long Valley region in the last seven days, all below magnitude 2.0, and located in the Sierra Nevada south of the caldera.
LONG VALLEY OBSERVATORY WEEKLY UPDATE
Friday, December 9, 2011 3:47 PM PST (Friday, December 9, 2011 23:47 UTC)
LONG VALLEY VOLCANIC CENTER VOLCANO (CAVW #1203-14-) 37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m) Current Volcano Alert Level: NORMAL Current Aviation Color Code: GREEN
Ten earthquakes occurred in the Mammoth Lakes-Long Valley region in the last seven days, all below magnitude 2.0. Four of the events were located in the Sierra Nevada south of the caldera. The others were located inside the caldera east of Mammoth Lakes.
LONG VALLEY OBSERVATORY WEEKLY UPDATE
Wednesday, November 16, 2011 11:07 AM PST (Wednesday, November 16, 2011 19:07 UTC)
LONG VALLEY VOLCANIC CENTER VOLCANO (CAVW #1203-14-) 37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m) Current Volcano Alert Level: NORMAL Current Aviation Color Code: GREEN
Thirty earthquakes occurred in the Mammoth Lakes-Long Valley region in the last seven days. All of the events were located in the Sierra Nevada south of the caldera. Magnitudes ranged between between M=1.0 and M=3.5, although only five of the thirty were M=2.0 or above. The magnitude M=3.5 earthquake, which occurred on November 14 at 2:33 PM PST, produced weak shaking in the town of Mammoth Lakes.
LONG VALLEY OBSERVATORY WEEKLY UPDATE
Monday, November 7, 2011 3:44 PM PST (Monday, November 7, 2011 23:44 UTC)
LONG VALLEY VOLCANIC CENTER VOLCANO (CAVW #1203-14-) 37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m) Current Volcano Alert Level: NORMAL Current Aviation Color Code: GREEN
Twelve earthquakes occurred in the Mammoth Lakes-Long Valley region in the past week (since 10:47PM PDT on October 31,2011). All of the events were between magnitude 1.0 and 1.8. Most were located in the Sierra Nevada south of Mammoth Lakes, but three were located in the caldera and one was located in Round Valley south of Toms Place .
LONG VALLEY OBSERVATORY WEEKLY UPDATE
Friday, October 14, 2011 2:04 PM PDT (Friday, October 14, 2011 21:04 UTC)
LONG VALLEY VOLCANIC CENTER VOLCANO (CAVW #1203-14-) 37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m) Current Volcano Alert Level: NORMAL Current Aviation Color Code: GREEN
Twenty earthquakes between magnitude 1.0 and 2.0 occurred in the Mammoth Lakes-Long Valley region in the past week (since 2:47 PM on Friday, October 7). All but one of these events (a magnitude 1.0 under Mammoth Mountain) were located in the Sierra Nevada to the south of the caldera.
LONG VALLEY OBSERVATORY WEEKLY UPDATE
Friday, September 30, 2011 3:57 PM PDT (Friday, September 30, 2011 22:57 UTC)
LONG VALLEY VOLCANIC CENTER VOLCANO (CAVW #1203-14-) 37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m) Current Volcano Alert Level: NORMAL Current Aviation Color Code: GREEN
Sixteen earthquakes between magnitude 1.0 and 2.9 occurred in the Mammoth Lakes-Long Valley region in the past week (since 7:02 PM on Friday, September 23). All but one of these events (a magnitude 1.0 in Round Valley) were located in the Sierra Nevada to the south of the caldera.
LONG VALLEY OBSERVATORY WEEKLY UPDATE
Friday, September 23, 2011 7:02 PM PDT (Saturday, September 24, 2011 02:02 UTC)
LONG VALLEY VOLCANIC CENTER VOLCANO (CAVW #1203-14-) 37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m) Current Volcano Alert Level: NORMAL Current Aviation Color Code: GREEN
Twenty earthquakes between magnitude 1.0 and 1.9 occurred in the Mammoth Lakes-Long Valley region in the past week. A total of five events were located in the caldera and the south flank of Mammoth Mountain, but the others were located in the Sierra Nevada to the south.