USGS Volcano Notice - DOI-USGS-AVO-2023-03-01T12:53:21-09:00

No significant seismicity was observed over the past day. Satellite images and web camera views were mostly cloudy during the last 24 hours.

Great Sitkin Volcano is monitored by local seismic and infrasound sensors, satellite data, web cameras, and regional infrasound and lightning networks.

The ongoing earthquake swarm at Takawangha volcano escalated and subsequently declined over the past day. Three earthquakes with magnitudes greater than M3.0 occurred yesterday afternoon and evening Alaska time (AKDT) near the volcano during the time period with the highest levels of seismicity. Since then, the swarm has declined and currently small earthquakes are occurring at the rate of about 5 to 10 events per hour. Satellite views of the volcano were mostly cloudy during the last 24 hours.

Takawangha volcano is monitored by local seismic and infrasound sensors, satellite data, and regional infrasound and lightning networks.

Small, shallow earthquakes (< 6 km depth) occurred at the rate of about 5 to 10 per hour over the past day at Aniakchak. The largest earthquake during the last 24 hours was M3.1. No significant activity was observed in mostly cloudy web camera views and satellite images.

The current period of seismic unrest began in October 2022. Increases in seismic activity have been detected previously at other similar volcanoes, with no subsequent eruptions. We expect additional shallow seismicity and other signs of unrest, such as gas emissions, elevated surface temperatures, and surface deformation to precede any future eruption, if one were to occur. 

AVO monitors Aniakchak with a local network, which consists of six seismometers, a web camera, and a single infrasound sensor, as well as satellite remote sensing data and regional infrasound and lightning networks. 

Small earthquakes occured at the rate of about 1 to 2 per hour in the vicinity of Trident Volcano during the past 24 hours. No significant activity was seen in mostly to partly cloudy web camera or satellite imagery.

The current period of seismic unrest began on August 24, 2022. Increases in seismic activity have been detected previously at Trident Volcano and other similar volcanoes, with no subsequent eruptions. We expect additional shallow seismicity and other signs of unrest, such as gas emissions, elevated surface temperatures, and surface deformation to precede any future eruption, if one were to occur. 

AVO monitors Trident Volcano with a local network of seismometers, a webcam, remote sensing data, and regional infrasound and lightning networks.

Low-level volcanic tremor was detected in seismic data over the past day. However, no noteworthy activity was observed in infrasound data. Satellite images were mostly cloudy during the last 24 hours. Clear web camera views showed minor steam and gas emissions at the north crater of Mount Young.

Small eruptions producing minor ash deposits within the vicinity of the active north crater of Mount Young and ash clouds usually under 10,000 ft (3 km) above sea level have characterized the recent periods of activity. Additional ash-producing events could occur again with little warning. 

Semisopochnoi volcano is monitored by local seismic and infrasound sensors, satellite data, web cameras, and regional infrasound and lightning networks.