Report on Davidof (United States) — 2 March-8 March 2022
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 2 March-8 March 2022
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2022. Report on Davidof (United States) (Sennert, S, ed.). Weekly Volcanic Activity Report, 2 March-8 March 2022. Smithsonian Institution and US Geological Survey.
51.97°N, 178.33°E; summit elev. 328 m
All times are local (unless otherwise noted)
According to AVO the earthquake swarm that began on 24 January in the vicinity at Davidof continued at least through 8 March with a few small earthquakes recorded each day by seismometers on Little Sitkin (15 km E). The earthquakes were shallow (less than 10 km deep) and the largest recorded during the last 7-10 days was a M 3.9. The swarm was either related to tectonic processes or volcanic unrest. The volcano is also monitored by satellite and remote infrasound and lightning networks. The Aviation Color Code remained at Yellow and the Volcano Alert Level remained at Advisory.
Geological Summary. A cluster of small islands between Segula and Little Sitkin in the western Aleutians, the largest of which is Davidof, are remnants of a stratovolcano that collapsed during the late Tertiary, forming a 2.7-km-wide caldera. The islands include Khvostof, Pyramid, Lopy, and Davidof; the latter three form the eastern rim of the mostly submarine caldera, sometimes referred to as the "Aleutian Krakatau." The islands were constructed above a roughly 100-m-deep submarine platform extending NW to Segula Island; the floor of the caldera lies 80 m below sea level. The islands are vegetated, but lava flows are recognizable, and Smith et al. (1978) suggested a possible Holocene age.