Report on Veniaminof (United States) — November 1983
Scientific Event Alert Network Bulletin, vol. 8, no. 11 (November 1983)
Managing Editor: Lindsay McClelland
Veniaminof (United States) Vapor plume; incandescence
Please cite this report as:
Global Volcanism Program, 1983. Report on Veniaminof (United States). In: McClelland, L (ed.), Scientific Event Alert Network Bulletin, 8:11. Smithsonian Institution. http://dx.doi.org/10.5479/si.GVP.SEAN198311-312070.
56.17°N, 159.38°W; summit elev. 2507 m
All times are local (unless otherwise noted)
Eruptive activity continued through November. Perryville residents observed glow over the volcano at night through the week of 13-19 November. On 16 November and the few nights preceding, the glow was the brightest observed since Strombolian activity resumed in early October. They saw steam on 16 November and heard rumbling from the volcano. On 18 November they observed a large billowing vapor cloud with no ash and again heard rumbling. On 23 November, a small amount of ash and steam rose from the intra-caldera cone, but no incandescence was observed. On the evening of 30 November, they observed a very small steam cloud with no ash, but they saw no glow over the volcano. Bad weather has prevented any overflights by USGS personnel since 4 November.
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: M.E. Yount and T. Miller, USGS, Anchorage.