Alaska Volcano Observatory

Lava continues to erupt slowly at Great Sitkin Volcano. Ongoing activity is adding to a thick lava flow that fills most of the summit crater with minor advancement of the northern part of the eastern lobe. Small earthquakes associated with the ongoing lava eruption continue. Nothing unusual was observed in cloudy satellite and web camera imagery.  

A single explosive event occurred in May 2021 and was followed by the ongoing eruption of lava that began in July 2021. No explosive events have occurred since May 2021. Local seismic and infrasound sensors and web cameras are used to monitor Great Sitkin along with regional infrasound and lightning networks and satellite data.

No major changes were detected in the past day at Mount Spurr. Seismicity remains elevated with several small earthquakes detected. No unusual activity was observed in satellite or web camera data over the past day.

AVO continues to closely 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 proceeded by additional signals that would allow advance warning.

Local seismic, infrasound, web cameras, and GNSS stations are used to monitor Mount Spurr along with regional infrasound, lightning networks and satellite data.
 

Strong southwesterly winds in the vicinity of Katmai and the Valley of Ten Thousand Smokes have picked up loose volcanic ash erupted during the 1912 Novarupta-Katmai eruption and carried it to the northwest. The National Weather Service has issued a SIGMET for this low-level event and suggests that the maximum cloud height is 6,000 ft above sea level.

This phenomenon is not the result of recent volcanic activity and occurs during times of high winds and dry snow-free conditions in the Katmai area and other young volcanic areas of Alaska. No eruption is in progress.

Resuspended volcanic ash should be considered hazardous and could be damaging to aircraft and health. For more information on volcanic ash and human health, visit the following website: http://volcanoes.usgs.gov/ash/. Official warnings about these ash resuspension events are issued by the National Weather Service: https://www.weather.gov/afc/. Forecasts of airborne ash hazard to aircraft: https://www.weather.gov/aawu/. Volcanic Ash Advisories: https://www.weather.gov/vaac/. Forecasts of ash fall: http://www.weather.gov/afc. Air quality hazards and guidance from Alaska Department of Environmental Conservation, Division of Air Quality: http://dec.alaska.gov/Applications/Air/airtoolsweb/Advisories/Index