ALASKA VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Friday, January 6, 2012, 11:17 AM AKST (Friday, January 6, 2012, 20:17 UTC)

CLEVELAND VOLCANO (VNUM #311240)
52°49'20" N 169°56'42" W, Summit Elevation 5676 ft (1730 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

Satellite views of Cleveland Volcano throughout the past week have indicated nothing unusual and no signs of eruptive activity have been observed. AVO has received no reports of activity at the volcano from pilots or other observers.

Satellite data indicate that the lava dome that formed throughout the fall-winter of 2011 was largely removed by the explosive activity of last week. It is uncertain if eruptive activity at Cleveland has ended, paused, or is occurring at a level below our detection capabilities. It remains possible for intermittent, sudden explosions of blocks and ash to occur at any time, and ash clouds exceeding 20,000 feet above sea level may develop. Such explosions and their associated ash clouds may go undetected in satellite imagery for hours. If a large, explosive, ash-producing event occurs, seismic, infrasound, or volcanic lightning may be detected by local and regional monitoring networks. There is no real-time seismic monitoring network on Mount Cleveland.

Additional information on Cleveland Volcano and the current activity may be found at this link:
http://www.avo.alaska.edu/activity/Cleveland.php

Please see http://www.avo.alaska.edu/color_codes.php for complete definitions of Aviation color codes and Volcano alert levels.



Cleveland volcano forms the western half of Chuginadak Island, a remote and uninhabited island in the east central Aleutians. It is located about 75 km (45 mi.) west of the community of Nikolski, and 1500 km (940 mi.) southwest of Anchorage. The volcano's most recent significant eruption began in February, 2001 and it produced 3 explosive events that produced ash clouds as high as 12 km (39,000 ft) above sea level. The 2001 eruption also produced a rubbly lava flow and hot avalanche that reached the sea. The most recent minor ash emissions were observed in January and June 2009.



CONTACT INFORMATION:

John Power, Scientist-in-Charge, USGS
jpower@usgs.gov (907) 786-7497

Chris Nye, Acting Coordinating Scientist
cnye@giseis.alaska.edu (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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