ALASKA VOLCANO OBSERVATORY STATUS REPORT
U.S. Geological Survey
Saturday, October 22, 2011, 11:37 AM AKDT (Saturday, October 22, 2011, 19:37 UTC)

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

Weather conditions were cloudy at Cleveland volcano over the last 24 hours preventing satellite observations of the summit. AVO has received no other reports of activity.

The edge of the dome is near the level of the crater rim on the southwest and east-northeast sides. Continued growth of the lava dome may result in lava flowing over the crater rim to produce a lava flow, and/or collapse of a flow front or dome flank to produce pyroclastic flows. Although lava could continue to erupt without generating an explosion, the growth of a lava dome in the summit crater increases the possibility of an explosive event. Explosions from the summit vent may produce ash clouds exceeding 20,000 ft above sea level with little to no warning, and could go undetected in satellite imagery for hours. However, lightning associated with significant ash-producing events may be detected sooner using an automated alarm system.

AVO does not have a real-time seismic network on the volcano and thus we are unable to track local earthquake activity related to volcanic unrest, provide forecasts of eruptive activity, or rapid confirmation of explosive, ash-producing events. In the event of a large explosive eruption like that in 2001, it is possible that seismic signals may be recorded on AVO seismic networks at nearby volcanoes. AVO will continue to monitor the volcano using multiple sources of satellite, lightning detection, and distant seismic data.



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

Jessica Larsen, Acting Coordinating Scientist, UAF
faust@gi.alaska.edu (907) 474-7992

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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