USGS Volcano Notice - DOI-USGS-AVO-2022-06-26T11:17:51-08:00

Low-level eruption of lava continues at Great Sitkin. Cloudy weather conditions obscured the volcano in web-cam and satellite 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. Low amplitude tremor was observed in seismic data during the past day with just a few small low frequency earthquakes. No activity was observed in cloudy satellite views. Robust steam emissions could be seen in web camera views. No ash emissions were observed. 

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. Clouds obscured satellite images of the volcano over the past day. Seismicity over the past day has been quiet.  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.