Alaska Volcano Observatory

Satellite radar data collected on August 16 show that lava continues to erupt in the summit crater of Great Sitkin Volcano. Small earthquakes and rockfall signals were detected over the past day. Webcam and satellite views were obscured by clouds. 

The current lava eruption began in July 2021 and has 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 and web cameras, and regional infrasound and lightning networks.

Low-level unrest continues at Mount Spurr with occasional, small earthquakes occurring beneath the volcano. Clear webcam and satellite views over the past day showed no unusual activity. 

Fluctuations in unrest are common at volcanoes and eruptive activity remains possible, but unlikely. Should unrest escalate towards an eruption, we expect to observe increases in seismic activity, gas emissions, surface deformation, and surface heating.

The volcano is monitored using local seismic, infrasound, web camera, and GNSS (GPS) stations along with regional infrasound, lightning networks, and satellite data.