ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Sunday, October 24, 2021, 11:51 AM AKDT (Sunday, October 24, 2021, 19:51 UTC)

SEMISOPOCHNOI VOLCANO (VNUM #311060)
51°55'44" N 179°35'52" E, Summit Elevation 2625 ft (800 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Eruptive activity continues at the north crater of Mount Cerberus. Explosions and tremor were detected in seismic and infrasound data over the past day. Low level (<10,000 ft) ash emissions and robust steam plumes were observed in partly cloudy web camera imagery over the course of the day. Satellite views were obscured by clouds.

Small eruptions producing minor ash deposits within the vicinity of the active north crater of Mount Cerberus and ash clouds usually under 10,000 feet above sea level have characterized the recent activity, which shows no signs of abating. Small explosions may continue to occur and could be difficult to detect, especially during poor weather conditions.

Semisopochnoi Island is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.


GREAT SITKIN VOLCANO (VNUM #311120)
52°4'35" N 176°6'39" W, Summit Elevation 5709 ft (1740 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Seismicity remains slightly elevated and no explosive activity has been observed in seismic or infrasound data over the past day. Clouds obscured satellite and web camera images of the volcano, but lava effusion likely continues.

There is no indication of how long lava effusion will continue during the current eruption, and it is possible that explosive activity could occur with little or no warning.

Great Sitkin Volcano is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.

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

Seismicity remains elevated, with tremor and small explosions detected over the past day. Clouds have obscured satellite and web cameras views, but these explosions likely produced short-lived low-level ash emissions.

Small explosions accompanied by low-level ash emissions could happen at any time, and are typically a hazard in the immediate vicinity of the summit. The level of unrest at Pavlof can change quickly and the progression to more significant eruptive activity can occur with little or no warning.

Pavlof Volcano is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.


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

David Fee, Coordinating Scientist, UAF, dfee1@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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