Report on Veniaminof (United States) — March 1987
Scientific Event Alert Network Bulletin, vol. 12, no. 3 (March 1987)
Managing Editor: Lindsay McClelland
Veniaminof (United States) Steam and ash emission
Please cite this report as:
Global Volcanism Program, 1987. Report on Veniaminof (United States). In: McClelland, L (ed.), Scientific Event Alert Network Bulletin, 12:3. Smithsonian Institution. http://dx.doi.org/10.5479/si.GVP.SEAN198703-312070.
56.17°N, 159.38°W; summit elev. 2507 m
All times are local (unless otherwise noted)
At 1315 on 19 March Northern Air Cargo pilot Wallace Niles observed steam and ash emission from the summit. The plume rose 200 m and trailed SW for up to 40 km. Reeve Aleutian pilot Edward Livingston had observed minor steam emission but no ash at 0900 that day.
Geologic Background. Massive Veniaminof volcano, one of the highest and largest volcanoes on the Alaska Peninsula, is truncated by a steep-walled, 8 x 11 km, glacier-filled caldera that formed around 3700 years ago. The caldera rim is up to 520 m high on the north, is deeply notched on the west by Cone Glacier, and is covered by an ice sheet on the south. Post-caldera vents are located along a NW-SE zone bisecting the caldera that extends 55 km from near the Bering Sea coast, across the caldera, and down the Pacific flank. Historical eruptions probably all originated from the westernmost and most prominent of two intra-caldera cones, which reaches an elevation of 2156 m and rises about 300 m above the surrounding icefield. The other cone is larger, and has a summit crater or caldera that may reach 2.5 km in diameter, but is more subdued and barely rises above the glacier surface.
Information Contacts: J. Reeder, ADGGS.