USGS Volcano Notice - DOI-USGS-AVO-2026-06-07T19:22:05+00:00

Slow eruption of lava continues. Minor seismicity detected over the past day. Typical slightly elevated surface temperatures were observed in satellite data. 

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.

Occasional earthquakes continued over the past day. Steaming from the fumarole field field located to the west of the summit of Mount Kupreanof was observed in high spatial resolution satellite image yesterday from afternoon. No other activity was observed in satellite data. 

There is no real-time geophysical monitoring network at Mount Kupreanof. The closest functioning seismometers are approximately 17 miles (27 km) to the east 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. 

Unrest continues. Minor seismic activity and infrasound were detected at the volcano.  Numerous pilot reports of steam emissions were received yesterday afternoon. The plume was longer than usual, but this is likely due to favorable atmospheric conditions and not increased volcanic gas emissions. Satellite data from yesterday afternoon showed typical sulfur dioxide emissions from the volcano. No other activity was observed in satellite data.

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.