ALASKA VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Friday, May 29, 2009, 3:41 PM AKDT (Friday, May 29, 2009, 23:41 UTC)

REDOUBT VOLCANO (VNUM #313030)
60°29'7" N 152°44'38" W, Summit Elevation 10197 ft (3108 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

The 2009 Redoubt eruption continues. Small discrete earthquakes and rockfall signals in the summit region have been recorded steadily over the course of the past week. Poor weather has obscured frequent views of the summit since Monday and it is difficult to evaluate the degree of change at the dome this week. Gas emissions measured on Monday showed a steep decline since last measured on May 14. Additional measurements are scheduled for early next week.

Since the last explosion at Redoubt on April 4, the lava dome has extended slowly down the steep north slope of the volcano. Additional explosions are still possible. In addition, this large mass of hot lava could fail in an avalanche with little or no warning. Either event could send ash over 30,000 feet above sea level, produce lahars in the Drift River valley, and deposit trace to minor amounts of ash on communities in south-central Alaska.

AVO continues to monitor Redoubt volcano closely and the operations center in Anchorage is staffed 24/7. AVO will provide frequent updates of the volcano's status and the earliest possible warning of significant explosive activity and other hazardous phenomena.

OTHER ALASKA VOLCANOES

Seismic activity is monitored in real time at 31 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, Iliamna, Isanotski, Kanaga, Katmai, Korovin, Mageik, Makushin, Martin, Novarupta, Okmok, Pavlof, Shishaldin, Snowy, Spurr, Tanaga, Trident, Ugashik-Peulik, Ukinrek Maars, Westdahl, and Wrangell 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 volcano.

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:

Tom Murray, Scientist-in-Charge, USGS
tlmurray@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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