Alaska Volcano Observatory

Iliamna volcano debris avalanche photo by Dennis Anderson, taken on Diamond Ridge near Homer. AVO detected seismic and pressure sensor signals associated with a debris avalanche on Red Glacier on the flank of Iliamna Volcano around 4:05 p.m. Alaska Daylight Time on Thursday, June 20, 2019 (00:00 UTC on June 21, 2019). Avalanche events are somewhat common at this volcano. The most recent prior to last week's occurred in April 2019. The seismic signals from the avalanche were observed on volcano monitoring networks on Illiamna and Redoubt volcanoes. Infrasound from this slide was detected with pressure sensors in Dillingham, Fairbanks, and those on the EarthScope Transportable Array. The avalanche and subsequent seismicity and infrasound are not considered to be indicative of volcanic unrest.