USGS Volcano Notice - DOI-USGS-AVO-2026-03-29T19:14:46+00:00

Lava continues to erupt slowly within the summit crater of Great Sitkin Volcano. Small earthquakes and numerous rockfalls were detected over the past day. Clouds obscured satellite and webcam images.

The current lava eruption began in July 2021 and, since then, 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, webcams, and regional infrasound and lightning networks.

Unrest continues at Shishaldin Volcano. Seismic and infrasound activity remains elevated, with numerous small earthquakes, seismic tremor, and infrasound signals observed over the past day. Satellite images detected sulfur dioxide emissions drifting to the northwest. Clouds obscured webcam and other satellite images.

Local seismic and infrasound sensors, web cameras, and a geodetic network are used to monitor Shishaldin Volcano. In addition to the local monitoring network, AVO uses nearby geophysical networks, regional infrasound and lightning data, and satellite images to detect eruptions. 

Low-level unrest continues at the Atka volcanic complex with weak tremor and numerous small earthquakes observed in seismic data. Satellite images detected weak sulfur dioxide emissions drifting to the northwest.

The Atka volcanic complex includes several vents, including Korovin Volcano, Mount Kliuchef and Sarichef Volcano. Korovin has been the site of most historical eruptions that typically produce minor amounts of ash and occasional but small lava flows. The Atka volcanic complex is monitored by local seismic and infrasound sensors and webcam, satellite data, and regional lightning detection instruments.