Alaska Volcano Observatory

Activity at Great Sitkin Volcano has remained unchanged over the past week, with lava continuing to erupt at a slow rate in the summit crater. Intermittent, small volcanic earthquakes continue at a low rate. Satellite and web camera images were obscured by clouds over the past week. 
   
Since the May 2021 explosion, there have been no other explosions at Great Sitkin Volcano. The lava eruption that began in July 2021 is ongoing. It has filled most of the summit crater and advanced into valleys below. The volcano is monitored using local seismic and infrasound sensors, satellite data and web cameras, and regional infrasound and lightning networks. 

Unrest persists at Mount Spurr with small, shallow earthquakes beneath the summit continuing over the past week. Satellite and web camera observations were mostly obscured by clouds over the past week, but no activity was observed during brief periods of clear weather. 
   
AVO continues to closely monitor activity at Mount Spurr for signals that would indicate that the volcano is moving closer to an eruption using local seismic, infrasound, web camera, and GNSS stations along with regional infrasound, lightning networks and satellite data. Based on previous eruptions, additional changes in earthquakes, ground deformation, the summit lake, and fumaroles would be expected if magma begins to move closer to the surface. Therefore, it is very likely that if an eruption were to occur it would be preceded by additional signals that would allow advance warning.