ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Tuesday, June 21, 2022, 10:53 AM AKDT (Tuesday, June 21, 2022, 18:53 UTC)
Low-level eruption of lava continues at Great Sitkin. Weakly elevated surface temperatures were observed in satellite images of the volcano from the past day. Cloudy weather conditions obscured the volcano in web-cam views. Seisimicity remains low. It is possible that new explosive activity could occur with little or no warning.
Great Sitkin is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.
Pavlof Volcano continues to erupt from the vent on the east flank just below the volcano’s summit. Seismic tremor and elevated surface temperatures were observed over the last day and reflect the continued eruption of a small lava flow on the upper part of the volcano. No explosions were detected.
Small explosions associated with the current eruption could happen at any time and may be accompanied by small ash plumes within the immediate vicinity of the volcano. 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 is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.
Low-level eruptive activity continues. Periods of weak seismic tremor and small low frequency earthquakes were observed on the local network. No activity was observed in cloudy satellite and web-cam views over the past day.
Small eruptions producing minor ash deposits within the vicinity of the active north crater of Mount Cerberus and ash clouds usually under 10,000 ft (3 km) above sea level have characterized the recent activity. Small explosions and associated ash emissions may continue and could be difficult to detect, especially when thick cloud cover obscures the volcano.
Semisopochnoi is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.
Unrest continues at Cleveland. Moderately elevated surface temperatures were observed at the summit of the volcano in satellite images from this morning. Sulfur dioxide emissions were oberved in satellite data. A few small earthquakes were recorded on the single local seismic station during the past day. No significant infrasound activity was detected on local or regional networks.
Episodes of lava effusion and explosions can occur without advance warning. Explosions from Cleveland are normally short duration and only present a hazard to aviation in the immediate vicinity of the volcano. Larger explosions that present a more widespread hazard to aviation are possible but are less likely and occur less frequently.
When operational, Cleveland volcano is monitored by only two seismic stations, which restricts AVO's ability to precisely locate earthquakes and 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.
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/
FOLLOW AVO ON FACEBOOK: https://facebook.com/alaska.avo
FOLLOW AVO ON TWITTER: https://twitter.com/alaska_avo
Michelle Coombs, Scientist-in-Charge, USGS email@example.com (907) 786-7497
David Fee, Coordinating Scientist, UAFGI firstname.lastname@example.org (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.