Veniaminof, Alaska Peninsula, Alaska

ERUPTIVE HISTORY

Location: 56.2N, 159.4W
Elevation: 8,223 feet (2,507 m)
Last Updated: January 10, 2005


A steaming cinder cone on the western floor of the summit caldera of Veniaminof volcano was the source of the dark lava flow that melted through the glacial icecap. This photo was taken from the SE on June 15, 1984, two months after the eruption ended, and shows the rim of the 8 x 11 km wide caldera in the background. The caldera rim is breached by Cone Glacier on the west side (at the extreme left) and is completely overtopped by glaciers on the south and SE sides. Veniaminof is one of the most voluminous and most active volcanoes on the Alaska Peninsula.
Photo by U.S. Geological Survey, 1984.


Veniaminof is a large stratovolcano that suffered a huge caldera-forming eruption about 3,700 years ago. The caldera is almost 6 miles (10 km) across and filled with ice and snow. All the recent eruptions have taken place from a cinder cone that pokes up through the ice in the caldera. Both the 1983-84 and June 1993-present eruption have consisted of fountaining at this cinder cone. Additionally, lava flows flow down the sides of the cone and onto the ice surface where they then melt their way down through to the bottom of the caldera and then a lake forms. This photo s hows active lava flows on January 23, 1984. Flows from November 1983 are covered with snow.


Veniaminof caldera with a lava flow from the central cone, filling a large pit melted out of the summit ice cap , January 1984.
Image Credit: Photo by M. E. Yount, (USGS).

There are very few people who live nearby so the danger to humans is pretty small. One of the things they worry about is called a jokulhlaup. This is an unpronounceable Icelandic word. A jokulhlaup happens when an eruption occurs under a thick ice sheet. The eruption will often melt the bottom of the glacier. If the eruption keeps on long enough pretty soon the glacier will float up on its own melted water (ice floats). As soon as this happens all that melted water can escape out from under the glacier and you get a big flood. This happens pretty often in Iceland, and it is a possibility at Veniaminof.


Eruption of Veniaminof on January 23, 1984. From front cover of USGS in Alaska: Accomplishments during 1983.

Click here to see summaries of the 1993 and 1994 eruptions at Veniaminof.

Sources of Information:

Alaska Volcano Observatory bimonthly reports.

Byers, F.M., 1955, Geology of Umnak and Bogoslof Islands Aleutian Islands Alaska: U.S. Geology

Miller, T.P., and Smith, R.L., 1987, Late Quaternary caldera-forming eruptions in the eastern Aleutian arc, Alaska: Geology, v. 15, p. 434-438.

Simkin, T., and Siebert, L., 1994, Volcanoes of the World: Geoscience Press, Tucson, Arizona, 349 p.

Wood, C.A., and Kienle, J., 1993, Volcanoes of North America: Cambridge University Press, New York, 354 p.

Yount, M.E., Miller, T.P., Emanuel, R.P., and Wilson, F.H., 1985, Eruption in an ice-filled caldera, Mount Veniaminof, Alaska Peninsula, in Bartsch-Winkler, S., and Reed, K.M. (eds.), USGS in Alaska: Accomplishments during 1983: U.S. Geological Circular 9 45, p. 58-60. 


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