USGS Volcano Notice - DOI-USGS-AVO-2026-07-29T18:29:38+00:00

Slow eruption of lava within the summit crater continues. Minor earthquakes were detected during the past 24 hours. Slightly elevated surface temperatures from the slowly growing lava dome were observed in satellite data over the past day. Web camera observations were obscured by clouds.

The current eruption began in July 2021 and, since then, lava flows have filled most of the summit crater and advanced into valleys below. There have been no explosions at Great Sitkin Volcano since an event in May 2021. The volcano is monitored using local seismic and infrasound sensors, satellite data, webcams, and regional infrasound and lightning networks.

Earthquake activity continues at a variable rate. A newly installed web camera located southwest of the summit showed steam emissions, which have been common during this period of unrest. No activity observed in satellite data.

While a new temporary monitoring station was installed in the last week near Mount Kupreanof, data are not yet available in real-time. The closest functioning seismometers are approximately 10 miles (16 km) to the northeast of the volcano as part of the Mount Veniaminof network. Mount Kupreanof is also monitored by satellite data, remote infrasound and lightning networks, and visual observations from pilots and mariners passing by the volcano.

Minor seismic activity and infrasound were detected at the volcano during the past day. Steam emissions were observed in satellite and web camera images over the past day, and produced a visible plume towards the south. The plume was longer than what has been observed recently, but it does not indicate a significant change in unrest. Typical sulfur dioxide gas emissions were observed in satellite data from yesterday afternoon. 

Local seismic and infrasound sensors, web cameras, and a geodetic network are used to monitor Shishaldin Volcano. In addition to the local monitoring network, AVO uses nearby geophysical networks, regional infrasound and lightning data, and satellite images to detect eruptions.