Alaska Volcano Observatory

A satellite radar image from May 29 confirms that lava is slowly advancing east in the summit crater at Great Sitkin Volcano. Cloud cover obscured other satellite and webcam images. Seismic activity remains low, with occasional small volcanic earthquakes and minor rockfalls within the crater.

The current lava eruption began in July 2021 and has filled most of the summit crater and advanced into the 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, and web cameras, and regional infrasound and lightning networks.

Earthquakes continue near Kupreanof Volcano, though most are minor and difficult to locate with regional seismometers. Cloud cover obscured satellite observations of the surface, but sulfur dioxide gas emissions were detected several times during the week.

There is no real-time geophysical monitoring network at Mount Kupreanof. The closest functioning seismometer is 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, regional infrasound and lightning networks, and visual observations from pilots and mariners passing by the volcano. 

Seismic and infrasound activity remain elevated, with numerous small earthquakes, frequent infrasound signals, and volcanic tremor recorded this week. Cloud cover obscured most satellite and webcam images, though occasional clear views showed minor steaming at the summit. Satellite data indicated elevated sulfur dioxide emissions on most days.

Shishaldin Volcano is monitored by local seismic and infrasound sensors, web cameras, and a telemetered geodetic network. In addition to the local monitoring network, the Alaska Volcano Observatory uses nearby geophysical networks, regional infrasound and lightning data, and satellite data to monitor the volcano.