ALASKA VOLCANO OBSERVATORY STATUS REPORT
U.S. Geological Survey
Tuesday, February 21, 2012, 12:48 PM AKST (Tuesday, February 21, 2012, 21:48 UTC)

KANAGA VOLCANO (VNUM #311110)
51°55'27" N 177°9'44" W, Summit Elevation 4288 ft (1307 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

No unusual seismicity was detected at Kanaga during the past 24 hours, and no unusual activity was observed in mostly clear satellite views. Photographs taken by a local observer on Sunday show a small steam plume issuing from the summit. AVO has received no reports of further explosive activity or ash clouds.

The possibility remains for sudden explosions of ash to occur at any time, and ash clouds exceeding 20,000 feet above sea level may develop. If a large, explosive, ash-producing event occurs, the local seismic network, satellite ash alarms, infrasound, and volcanic lightning will alert AVO to the new activity.




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

Partly cloudy satellite views over the past 24 hours show no unusual activity at Cleveland volcano.

The new, 60-meter-diameter (200 feet) lava dome occupies a small portion of the approximately 200 meter (650 foot) diameter summit crater. There have been no observations of ash emissions or explosive activity during this current lava extrusion. The lava dome that formed throughout the fall-winter of 2011 was largely removed by the explosive activity on 25 and 29 December, 2011.

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.

VOLCANO INFORMATION ON THE INTERNET: http://www.avo.alaska.edu
RECORDING ON THE STATUS OF ALASKA'S VOLCANOES (907) 786-7478

CONTACT INFORMATION:

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

Steve McNutt, Coordinating Scientist, UAF
steve@giseis.alaska.edu (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.

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