Alaska Volcano Observatory

Minor growth of the active lava dome within the summit crater was observed in satellite imagery over the past week. The southeast lava lobe is not advancing but lava continues to flow into it. The south flank of the dome is moving slowly southward and generating occasional small rockfalls. Steaming and elevated surface temperatures were observed in satellite and webcam views when weather was clear. Seismic activity remains low with occasional small volcanic earthquakes and signals from minor rockfalls caused by lava‑flow growth. 

The current lava eruption began in July 2021 and has filled most of the summit crater and advanced into the valleys below. There have been no explosions at Great Sitkin Volcano since an event in May 2021. The volcano is monitored using local seismic, geodetic, and infrasound sensors, satellite data, and web cameras, and regional infrasound and lightning networks. 

Volcanic activity remains slightly elevated. Small earthquakes, ongoing tremor, and possible infrasound signals have continued over the past week. During periods of clear weather, webcam views showed steaming from the summit area, and satellite data indicated minor sulfur dioxide emissions through much of the week. Overall, the frequency and magnitude of earthquakes, infrasound signals, and gas emissions have declined over recent months, indicating a gradual decrease in activity. 

Shishaldin Volcano is monitored by local seismic and infrasound sensors, web cameras, and a telemetered geodetic network. In addition to the local monitoring network, the Alaska Volcano Observatory uses nearby geophysical networks, regional infrasound and lightning data, and satellite data to monitor the volcano.