Report on Pavlof (United States) — 18 January-24 January 2023
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
18 January-24 January 2023
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2023. Report on Pavlof (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 18 January-24 January 2023. 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 the eruption at Pavlof has ended. No explosions had been detected since 11 December and seismicity had decreased to background levels. Weakly elevated surface temperatures and minor steaming from the recently active vent continue to be observed intermittently in satellite and webcam images, consistent with the cooling of previously erupted lava. On 19 January AVO lowered the Volcano Alert Level to Normal (the lowest level on a four-level scale) and the Aviation Color Code to Green (the lowest level on a four-color scale).
Geological Summary. The most active volcano of the Aleutian arc, Pavlof is a 2519-m-high Holocene stratovolcano that was constructed along a line of vents extending NE from the Emmons Lake caldera. Pavlof and its twin volcano to the NE, 2142-m-high Pavlof Sister, form a dramatic pair of symmetrical, glacier-covered stratovolcanoes that tower above Pavlof and Volcano bays. A third cone, Little Pavlof, is a smaller volcano on the SW flank of Pavlof volcano, near the rim of Emmons Lake caldera. Unlike Pavlof Sister, Pavlof has been frequently active in historical time, typically producing 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 historical 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.
Source: US Geological Survey Alaska Volcano Observatory (AVO)