ALASKA VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Friday, July 27, 2012, 11:42 AM AKDT (Friday, July 27, 2012, 19:42 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

Slightly elevated surface temperatures indicative of continued low-level unrest were observed in satellite images during clear periods over the past week. AVO has received no reports of activity from mariners or pilots in the vicinity of the volcano.

Sudden explosions of blocks and ash remain possible with little or no warning. Associated ash clouds could exceed 20,000 feet above sea level. If a large ash-producing event occurs, nearby seismic, infrasound, or volcanic lightning networks should detect the event and alert AVO staff. There is no real-time seismic monitoring network on Mount Cleveland and AVO is unable to track activity in real time.

ILIAMNA VOLCANO (VNUM #313020)
60°1'55" N 153°5'30" W, Summit Elevation 10016 ft (3053 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

No unusual activity has been observed or reported at Iliamna Volcano over the past week.

The current level of activity at Iliamna does not indicate an imminent or certain eruption. Seismic activity appears to be declining gradually. A similar seismic swarm occurred at Iliamna Volcano in 1996-1997 and was not followed by eruptive activity. Prior to an eruption, AVO would expect to see a significant increase in earthquake activity beneath the volcano.


OTHER ALASKA VOLCANOES

Seismic activity is monitored in real time at 29 volcanoes in Alaska. Satellite images of all Alaskan volcanoes are analyzed daily for evidence of ash plumes and elevated surface temperatures. Some volcanoes may currently display anomalous behavior but are not considered to be at a dangerous level of unrest. Akutan, Aniakchak, Augustine, Dutton, Fisher, Fourpeaked, Gareloi, Great Sitkin, Griggs, Isanotski, Kanaga, Katmai, Mageik, Makushin, Martin, Novarupta, Okmok, Pavlof, Redoubt, Shishaldin, Snowy, Spurr, Tanaga, Trident, Ugashik-Peulik, Ukinrek Maars, Veniaminof, and Westdahl volcanoes are in color code GREEN and volcano alert level Normal. All are at or near normal levels of background seismicity. AVO did not detect ash plumes or significant elevated surface temperatures in the vicinity of any of these volcanoes.

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

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
or
Steve McNutt Coordinating Scientist, UAF-GI
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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