ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Thursday, May 28, 2020, 10:05 AM AKDT (Thursday, May 28, 2020, 18:05 UTC)

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

Low level unrest continues at Great Sitkin. Occasional small earthquakes continue. No activity was observed in cloudy satellite and webcam images.

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

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

Low level unrest continues at Semisopochnoi. Seismicity remains above background with low-level tremor and occasional small earthquakes occurring over the past day. No other significant activity was detected in seismic data, and no eruptive activity was observed in regional infrasound data or in cloudy satellite images.

Semisopochnoi is monitored by local seismic sensors, satellite data, and lightning detection networks. An infrasound array on Adak Island may detect explosive emissions from Semisopochnoi with a slight delay (approximately 13 minutes) if atmospheric conditions permit.

SHISHALDIN VOLCANO (VNUM #311360)
54°45'19" N 163°58'16" W, Summit Elevation 9373 ft (2857 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

Low level unrest continues at Shishaldin. Seismicity remains above background with low-level tremor and occasional small earthquakes occurring over the past day. Moderate to weak elevated surface temperatures were observed in partly cloudy satellite views of the volcano and minor steaming was observed in web camera and satellite views. No explosive activity was detected on regional infrasound sensors.

Although unrest is currently at low levels, conditions could change rapidly with minimal warning, and eruptive activity in the summit crater could resume. If eruptive activity does resume, lava flows, lahars, and ash-producing events could occur.

Shishaldin is monitored by local seismic and infrasound sensors, satellite data, web cameras, a telemetered geodetic network, and distant 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, UAFGI
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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