ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Saturday, June 10, 2017, 11:56 AM AKDT (Saturday, June 10, 2017, 19:56 UTC)

BOGOSLOF VOLCANO (VNUM #311300)
53°55'38" N 168°2'4" W, Summit Elevation 492 ft (150 m)
Current Volcano Alert Level: WARNING
Current Aviation Color Code: RED

No new explosive activity has been observed at Bogoslof Volcano since the eruption this morning between 3:18 to 5:28 AKDT (11:18 to 13:28 UTC). The eruption this morning produced an ash rich cloud to an estimated altitude of 34,000 ft asl and a SIGMET aviation warning message for the cloud was issued by the National Weather Service. Please see the NWS AAWU at http://www.weather.gov/aawu/sigmets for updated information on aviation warning messages. A series of small, short-duration signals seen in seismic data following the explosive activity are consistent with low-level eruptive behavior. No detectable activity has been seen in seismic or infrasound data since 6:50 AKDT (14:50 UTC).

Bogoslof volcano remains at a heightened state of unrest and in an unpredictable condition. Activity may ramp back up with additional explosions producing high-altitude (>15,000 ft) volcanic clouds with little precursory activity. Some previous explosions have been preceded by an increase in earthquake activity that allowed for short-term forecasts of imminent significant explosive activity. Although we are able to detect energetic explosive activity in real-time, there is typically a lag of tens of minutes until we can characterize the magnitude of the event and the altitude of the volcanic cloud. It is possible for low-level unrest, including explosive activity, to occur that we are unable to detect with existing data sources. Such low-level periods of unrest and possible explosions could pose a hazard in the immediate vicinity of the volcano. A Temporary Flight Restriction (TFR) is in effect over the volcano at the present time. Please see http://tfr.faa.gov/tfr2/list.html for the status of the TFR.

AVO has no ground-based volcano monitoring equipment on Bogoslof volcano. We continue to monitor satellite images, information from the Worldwide Lightning Location Network pertaining to volcanic-cloud lightning, and data from seismic and infrasound instruments on nearby islands for indications of volcanic activity.

CLEVELAND VOLCANO (VNUM #311240)
52°49'20" N 169°56'42" W, Summit Elevation 5676 ft (1730 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Unrest continues. No activity has been observed in seismic or infrasound data from the past day and clouds obscured satellite observations. Slow lava effusion in the summit crater may be occurring.

Cleveland volcano is monitored with a limited real-time seismic network, which inhibits AVO's ability to detect precursory unrest that may lead to an explosive eruption. Rapid detection of an ash-producing eruption may be possible using a combination of seismic, infrasound, lightning, and satellite data.

PAVLOF VOLCANO (VNUM #312030)
55°25'2" N 161°53'37" W, Summit Elevation 8261 ft (2518 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

No significant activity has been detected in seismic or pressure sensor data during the past day. No activity has been observed in cloudy satellite and web camera images.

The degree of unrest at Pavlof can change quickly and progression to eruptive activity can occur with with little or no warning.

OTHER ALASKA VOLCANOES

Information on all Alaska volcanoes is available at : http://www.avo.alaska.edu.

For definitions of Aviation Color Codes and Volcano Alert Levels, see: http://www.avo.alaska.edu/color_codes.php

SUBSCRIBE TO VOLCANO ALERT MESSAGES by email: http://volcanoes.usgs.gov/vns/

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CONTACT INFORMATION:

Michelle Coombs, Scientist-in-Charge, USGS
mcoombs@usgs.gov (907) 786-7497

Jessica Larsen, Acting Coordinating Scientist, UAF
jflarsen@alaska.edu (907) 322-4085

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.

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