Alaska Volcano Observatory

Lava continues to erupt slowly in the summit crater of Great Sitkin Volcano, and small earthquakes continue at a low rate. Satellite and web camera images were obscured by clouds over the past day. 

The current eruption of Great Sitkin Volcano began with a single explosive event in May 2021. The ongoing eruption of lava at the summit began shortly afterward, in July 2021. The volcano is monitored using local seismic and infrasound sensors, satellite data and web cameras, and regional infrasound and lightning networks.

Unrest continues at Mount Spurr volcano. Seismicity remains elevated with occasional small volcanic earthquakes detected beneath the volcano over the past day. Satellite and web camera images from the past day showed continued steaming from the summit crater. This type of steaming is typical for Mount Spurr during this current period of unrest.

There were two non-volcanic earthquakes that were felt by residents throughout Southcentral Alaska over the past 12 hours. The first one at 11:19 PM AKDT yesterday evening was located southeast of Mount Spurr and the second one at 5:01 AKDT this morning was located under Cook Inlet west of Clam Gulch. Both of these earthquakes are due to typical tectonic activity and they are not due to activity at Mount Spurr. They will not cause additional unrest at the volcano, and unrest at the volcano will not cause an increase in this type of tectonic earthquake. The volcanic earthquakes that are occurring at Mount Spurr are too small to be felt, and even if an eruption were to occur it would not cause ground shaking in populated areas.

AVO continues monitoring activity at Mount Spurr for signals indicating that the volcano is moving closer to an eruption. Based on previous eruptions, changes from current activity in the earthquakes, ground deformation, summit lake conditions, and fumarolic activity would be expected if magma began to move closer to the surface. Therefore, if an eruption occurred, it would be preceded by additional signals allowing warning.

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