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ALASKA VOLCANO OBSERVATORY
Information Release
Monday, September 18, 2006 2:20 PM AKDT (2220 UTC)
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DOUGLAS VOLCANO
58°51'18"N 153°32'31"W, Summit Elevation 7021 ft (2140 m)
Current Level of Concern Color Code: Not Assigned
FOURPEAKED VOLCANO
58°46'12"N 153°40'19"W, Summit Elevation 6903 ft (2104 m)
Current Level of Concern Color Code: Not Assigned
On Sunday, September 17, AVO received several reports of two discrete plumes rising from the Cape Douglas area, about 200 miles (320 km) southwest of Anchorage, beginning at approximately 8:15 PM AKDT (0415 UTC, September 18) and continuing until darkness. Analysis of satellite images shows that the plumes originated in the area of Fourpeaked Glacier, located between Fourpeaked and Douglas volcanoes. Photographs of the plumes show that they reached up to approximately 20,000 ft (6,000 m) above sea level.
Satellite images show a cloud originating from Fourpeaked glacier area and persisting throughout the night. The cloud does not show an ash signature. The cloud traveled up to 12 miles (20 km) to the northeast.
Fourpeaked and Douglas volcanoes are not monitored seismically. Seismometers around the Katmai group of volcanoes, about 50 miles (80 km) to the southwest, and around Augustine volcano, 40 miles (64 km) to the north, did not record any unusual seismic activity. Based on the absence of an ash signature in the cloud in satellite data, a significant volcanic eruption did not occur. The origin of the two plumes is still unknown.
Poor weather in the area today prevents further visual observations. AVO will continue to monitor the area via satellite and local pilot reports. AVO will attempt an overflight of the area later this week.
Mount Douglas, a 2,140 m (7,020 ft) high stratovolcano, is located on the northern tip of the Alaska Peninsula, 320 km (200 mi) southwest of Anchorage. The summit of Mount Douglas has a small lake-filled crater, and an active fumarole field on the northeast crater wall. In 1982, the crater lake had a temperature of 25 degrees C (77 degrees F) and a pH of 1. Although Mount Douglas is dissected and eroded, lava flows on the northwest flank are relatively uneroded. Douglas has not experienced eruptive activity within historical times; the most recent eruption was in the early Holocene.
Fourpeaked Mountain lies within the northeast corner of Katmai National Park and Preserve on the Alaska Peninsula, 7.5 miles (12 km) southwest of Mount Douglas. It is the likely vent for Fourpeaked volcano, a stratovolcano that is mostly surrounded (and covered) by Fourpeaked Glacier. Small isolated volcanic exposures along ridge crests and cliff faces radiate out from the ice-covered summit. The last volcanic activity at Fourpeaked was probably greater than 10,000 years ago. No recent volcanic or hydrothermal activity has been identified.
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
CONTACT INFORMATION:
Tom Murray, Scientist-in-Charge, USGS
tlmurray@xxxxxxxx (907) 786-7497
Chris Nye, Acting-Coordinating Scientist, DGGS
cnye@xxxxxxxxxxxxxxxxx (907) 474-7430
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.
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