Printer friendly versionALASKA VOLCANO OBSERVATORY
Wednesday, September 28, 2005 12:45 PM AKDT (20:45 UTC)
VENIAMINOF VOLCANO CAVW#(1102-07-)
56.2 ° W 159.39 ° N, Summit Elevation 8225 ft (2507 m)
Current Level of Concern Color Code: GREEN
Previous Level of Concern Color Code: YELLOW
Seismic activity at Veniaminof Volcano has been at background levels for over a week. No seismic signals considered to be associated with ash bursts have been observed during the past two weeks. Cloudy conditions have persisted for more than two weeks preventing views of the voclano by satellite, web camera, and ground observers. AVO has received no reports of ash emissions from pilots or observers on the ground. There are no indications that more vigorous activity is imminent or even likely. Given the decline of the seismicity it appears that the most recent episode of activity has ended. The Level of Concern Color Code for Mount Veniaminof Volcano is thus downgraded from yellow to GREEN.
Mount Veniaminof volcano is an andesitic stratovolcano with an ice-filled 10-km diameter summit caldera located on the Alaska Peninsula, 775 km (480 mi) southwest of Anchorage and 35 km (22 mi) north of Perryville. Veniaminof is one of the largest (~ 300 km3) and most active volcanic centers in the Aleutian Arc and has erupted at least 12 times in the past 200 years. The most recent significant eruption of the volcano occurred in 1993-95 and was a moderate Strombolian eruption from the main intracaldera cone in the northwest sector of the caldera above Cone Glacier. The eruption was characterized by intermittent low-level emissions of steam and ash, and a small lava flow was extruded into the summit caldera ice field producing an ice pit. Minor ash-producing explosions occurred in 2002, 2004, early 2005, and in recent weeks. Previous historical eruptions have produced ash plumes that reached 6,000 m (20,000 ft) above sea level and ash fallout that blanketed areas within about 40 km (25 mi) of the volcano.
ABBREVIATED COLOR CODE KEY (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected at any time
VOLCANO INFORMATION ON THE INTERNET: http://www.avo.alaska.edu
RECORDING ON THE STATUS OF ALASKA'S VOLCANOES (907) 786-7478
Tom Murray, Scientist-in-Charge, USGS
firstname.lastname@example.org (907) 786-7497
Steve McNutt, Acting Coordinating Scientist, UAF-GI
email@example.com (907) 474-7131
The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.