USGS Volcano Notice - DOI-USGS-AVO-2026-06-24T19:23:43+00:00

Minor seismicity and small rockfalls were detected over the past day. Clouds obscured views of the active lava dome in satellite and webcam imagery.

The current eruption began in July 2021 and, since then, lava flows have 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.

Low-level unrest continues with minor earthquake activity. Sulfur dioxide gas emissions and weakly elevated surface temperatures from the fumarole field were observed in partly cloudy satellite imagery.

There is no real-time geophysical monitoring network at Mount Kupreanof. The closest functioning seismometers are approximately 17 miles (27 km) to the east of the volcano as part of the Mount Veniaminof network. Mount Kupreanof is also monitored by satellite data, remote infrasound and lightning networks, and visual observations from pilots and mariners passing by the volcano. 

Minor seismic activity and infrasound signals were detected at the volcano. The typical degassing plume from the summit crater with sulfur dioxide and steam emissions was observed in partly cloudy webcam and satellite views. 

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. 

A small explosion was detected in seismic and infrasound data at 5:59 AM AKDT (13:59 UTC) originating from the crater lake at Korovin Volcano, within the Atka Volcanic Complex. Brief explosive events at Korovin Volcano are not uncommon and can occur without significant precursory unrest. No emissions were detected associated with this activity and elevated seismicity declined immediately after the event.  

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.