USGS Volcano Notice - DOI-USGS-AVO-2025-02-10T21:36:54+00:00

Lava continues to erupt slowly in the summit crater of Great Sitkin Volcano. Seismicity has been quiet over the past day.  Clouds blocked views of the volcano in web camera and satellite images.

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, with numerous small, shallow volcanic earthquakes detected beneath the volcano over the past day. Currently, the earthquakes are being located under the Crater Peak vent as well as under the summit of Mount Spurr. Clear views of the volcano showed no unusual activity over the past day.  Airborne gas measurements from the Spurr summit and the Crater Peak vent collected on Friday February 7, show no significant changes in gas output from the volcano.  Sulfur dioxide and carbon dioxide gas are similar to background levels measured in previous years.  

AVO continues to monitor activity at Mount Spurr for signals that would indicate that the volcano is moving closer to an eruption. Based on previous eruptions, changes from current activity in the earthquakes, ground deformation, summit lake, and fumaroles would be expected if magma began 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.

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