Report on Pavlof (United States) — 12 June-18 June 2019
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
12 June-18 June 2019
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2019. Report on Pavlof (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 12 June-18 June 2019. Smithsonian Institution and US Geological Survey.
55.417°N, 161.894°W; summit elev. 2493 m
All times are local (unless otherwise noted)
On 12 June AVO reported that elevated levels of seismicity at Pavlof, recorded since mid-May, had declined to background levels. The Aviation Color Code was lowered to Green and the Volcano Alert Level was lowered to Normal. The report noted that vapor plumes were occasionally visible in webcam views and elevated surface temperatures in the summit crater were sometimes identified in satellite images; both are common occurrences at Pavlof.
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.