Report on Pavlof (United States) — March 1977
Natural Science Event Bulletin, vol. 2, no. 3 (March 1977)
Managing Editor: David Squires.
Pavlof (United States) Some steaming and ash near the summit
Please cite this report as:
Global Volcanism Program, 1977. Report on Pavlof (United States). In: Squires, D (ed.), Natural Science Event Bulletin, 2:3. Smithsonian Institution. http://dx.doi.org/10.5479/si.GVP.NSEB197703-312030.
55.417°N, 161.894°W; summit elev. 2493 m
All times are local (unless otherwise noted)
10 February, 1010-1640: no activity. Entire volcano covered with snow. 12 February, 1105-1355: steaming lightly. Part of cone covered with ash. 22 February, 0917-1625: no activity. Entire volcano covered with snow. 23 February, 0935-1710: no activity. 13 March, 1525: no activity. 16 March, 1530: overflight in private aircraft piloted by Capt. Young (USAF); steam was issuing from about 20 small vents in an ash-covered area approximately 50 m in diameter, l0 m below the base of the cone on the W slope. An older 30-m-diameter crater, partially filled with snow, was about 20 m below the base of the cone on the N slope.
Geologic Background. 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.
Information Contacts: R. Dean, USAF, Cold Bay.