Report on Pavlof (United States) — 13 July-19 July 2022
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 13 July-19 July 2022
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2022. Report on Pavlof (United States) (Sennert, S, ed.). Weekly Volcanic Activity Report, 13 July-19 July 2022. Smithsonian Institution and US Geological Survey.
55.417°N, 161.894°W; summit elev. 2493 m
All times are local (unless otherwise noted)
AVO reported that a minor eruption at a vent on Pavlof’s upper E flank was ongoing during 12-19 July. Seismic tremor persisted and multiple daily explosions were detected in seismic and infrasound data. Elevated surface temperatures identified in satellite images on a few of the days possibly reflected ongoing minor lava effusion; cloud cover prevented views on most of the days during the week. Minor ash emissions were seen in webcam images during 18019 July. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange.
Geological Summary. The most active volcano of the Aleutian arc, Pavlof is a Holocene stratovolcano that was constructed along a line of vents extending NE from the Emmons Lake caldera. Pavlof and Pavlof Sister to the NE form a dramatic pair of symmetrical, glacier-covered stratovolcanoes that overlook Pavlof and Volcano bays. Little Pavlof is a smaller cone on the SW flank of Pavlof volcano, near the rim of Emmons Lake caldera. Unlike Pavlof Sister, eruptions have frequently been reported from Pavlof, typically Strombolian to Vulcanian explosive eruptions from the summit vents and occasional lava flows. The active vents lie near the summit on the north and east sides. The largest recorded eruption took place in 1911, at the end of a 5-year-long eruptive episode, when a fissure opened on the N flank, ejecting large blocks and issuing lava flows.