Hypocenters of located earthquakes (past 3 days) at Davidof, Dec 10, 2021.

Hypocenters of located earthquakes (past 3 days) at Davidof, Dec 10, 2021.

Date: Dec 10th, 2021
Volcano(es): Davidof
Photographer: Alaska Volcano Observatory
URL: avo.alaska.edu/image/view/180031

Davidof 2021 unrest

On Dec 10, 2021, AVO raised the Aviation Color Code and Volcano Alert Level at Davidof to YELLOW/ADVISORY, stating "Over the past three days a swarm of earthquakes has occurred in the vicinity of Davidof volcano. The largest earthquake to date happened this morning at about 19:45 UTC (10:45 am AKST) and had a magnitude of 4.2. This swarm may be associated with volcanic unrest or it could also be due to regional tectonic activity. Due to the possibility of escalating volcanic unrest, AVO is raising the Aviation Color Code and Volcano Alert Level for Davidof to YELLOW/ADVISORY. AVO is continuing to monitor the situation with seismometers deployed on nearby islands since there is no real-time seismic monitoring network at Davidof volcano. The closest seismometers to Davidof are approximately 15 km to the east of the volcano on Little Sitkin Island."
On December 29, AVO lowered the Aviation Color Code and Volcano Alert Level at Davidof to UNASSIGNED, stating that the "swarm of earthquakes that occurred in the vicinity of Davidof volcano beginning in early December has subsided. Thus, the Aviation Color Code and Alert Level is being decreased to UNASSIGNED/UNASSIGNED. AVO only assigns color code and alert level values to volcanoes that are sufficiently instrumented to allow us to understand the background state of activity."
AVO raised Davidof to YELLOW/ADVISORY again on January 26, 2022, stating "over the past two days a swarm of earthquakes has occurred in the vicinity of Davidof volcano. The largest earthquake in the current sequence happened yesterday at 4:02 PM AKST (January 26, 01:02 UTC) and had a magnitude of 4.9. A similar earthquake swarm occurred in December 2021. No signs of unrest have been observed in recent satellite images of the volcano."

Image courtesy of the AVO/ADGGS.
Please cite the photographer and the Alaska Volcano Observatory / Alaska Division of Geological & Geophysical Surveys when using this image.
Full Resolution.