USGS Volcano Notice - DOI-USGS-AVO-2026-06-15T20:03:21+00:00

Minor seismicity was detected over the past day. Weakly 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.

One earthquake located near Mount Kupreanof in the last day was greater than magnitude 3. Clouds obscured satellite views of the volcano but diffuse sulfur dioxide gas emissions were detected downwind. 

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. 

Minor seismic activity and infrasound signals were detected at the volcano. Clear web camera views showed steaming from the vent. Sulfur dioxide gas emissions were 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.