ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Wednesday, December 21, 2016, 1:47 PM AKST (Wednesday, December 21, 2016, 22:47 UTC)

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

A short-lived eruption occurred at Bogoslof yesterday late afternoon producing a small eruption cloud that quickly detached and moved southeastward. The cloud-forming eruption started at around 3:30 pm AKST, 20 Dec 2016 (00:30 UTC, 21 Dec 2016) with a weak seismic signal visible on stations located on nearby islands and a continuous signal lasting ~25 minutes on the Dillingham infrasound array. Within an hour of the eruption pilots reported the eruptive activity to be declining and the cloud dispersing.

Seismicity recorded by instruments on nearby volcanoes indicates that unrest continues. Periods of discrete earthquakes and continuous seismic tremor are occurring. No evidence of explosive activity has been detected by regional infrasound networks today, and mostly clear satellite images from this morning show no evidence of ash emissions or elevated surface temperatures.

AVO has no ground-based volcano monitoring equipment on Bogoslof volcano and is unable to provide a forecast of future eruptive activity. We are monitoring satellite images and data from distant seismic and infrasound instruments for indications of significant explosive activity.


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

Unrest continues at Pavlof Volcano. No significant activity was observed in cloudy satellite and web camera images today. Nothing significant was detected in seismic or pressure sensor data during the past day.

The degree of unrest at Pavlof can change quickly. A return to eruptive activity can occur with with little or no warning. AVO is closely monitoring the volcano.

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

Low-level unrest continues at Cleveland. No significant activity observed in mostly clear satellite images today. Recent clear web camera images show minor, low-level steam emission from the summit. No significant activity was detected in seismic or pressure sensor data during the past 24 hours.

OTHER ALASKA VOLCANOES

Other Alaska volcanoes show no signs of significant unrest: http://www.avo.alaska.edu/activity/

AVO scientists conduct daily checks of earthquake activity at all seismically-monitored volcanoes, examine web camera and satellite images for evidence of airborne ash and elevated surface temperatures, and consult other monitoring data as needed.

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

FOR MORE INFORMATION ON ALASKA VOLCANOES: http://www.avo.alaska.edu

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

Janet Schaefer, Acting Coordinating Scientist, DGGS
janet.schaefer@alaska.gov (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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