6 April, 1118: pilot reported ash extensively covering entire expanse of Pavlof's SE flank. Black smoke and intermittent steam were observed. 14 April, 0900-1900: steaming intermittently; 2 ash sprays visible on NW flank. 15 April, 0600-0700; 25 April 2300; and 27 April 1200-1900: steam emissions. 29 April, 1500: a pilot reported the volcano steaming. The entire E flank was reported to be ash-covered and very black. 30 April, 1200-1900: Although difficult to differentiate between ash and exposed rock (when viewed from Cold Bay, 60 km to the W) there appeared to be ash over the upper 100 m of the cone and along several radial areas along the near (SW) flank. Pavlof apparently produced extensive ash during the last few days of the month.

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.

Information Contacts: P. Sventek, USAF, Cold Bay.