Printer friendly versionALASKA VOLCANO OBSERVATORY
Friday, April 14, 2006 1:20 PM AKDT (2120 UTC)
59°21'48"N 153°26'W , Summit Elevation 4134 ft (1260 m)
Current Level of Concern Color Code: ORANGE
Activity at Augustine Volcano has declined to low levels over the past week. Seismic activity has diminished but is still slightly above background and the frequency of rock falls and avalanche events has decreased over the past week. However, low-level eruptive activity, consisting of slow effusion of lava at the summit, accompanied by small rock fall and avalanche events on the flanks of the volcano is still occurring. Small volume, dilute ash clouds resulting from rock falls and avalanches may be produced, but are not likely to extend much beyond the immediate vicinity of the volcano. During very high wind conditions, minor amounts of ash could be swept from the flanks of the volcano and carried longer distances.
Satellite images of the volcano obtained over the past several weeks also indicate declining thermal output consistent with the decrease in activity. Airborne sulfur dioxide gas measurements obtained this week show continued high levels of magmatic gas emission and this could be associated with degassing of lava at the summit of the volcano.
The dome-building eruptive activity that has characterized the present phase of the 2006 eruption of Augustine Volcano may be coming to an end, and the volcano may be entering a quiescent period that could signify the end of the eruption or a temporary hiatus in activity. During past historical eruptions of Augustine Volcano, there have been periods of little to no activity that were followed by a resumption of vigorous eruptive activity. Thus, it is possible for conditions to change rapidly and for vigorous dome building activity to resume with little or no warning. If this were to happen, brief, energetic explosions of ash could resume and could produce significant amounts of ash and drifting ash clouds that could rise more than 25,000 feet above sea level.
AVO continues to monitor Augustine closely and the observatory remains staffed 24/7.
56°11'44"N 159°23'18"W , Summit Elevation 8225 ft (2507 m)
Current Level of Concern Color Code: YELLOW
Seismicity at Veniaminof Volcano remains low, but above background. Internet camera and satellite views have been obscured by cloudy weather this week, and AVO has received no new information about ash clouds or activity at Veniaminof.
Production of short-lived, very small-volume steam and ash bursts from the intracaldera cone has been typical of this volcano intermittently over the past few years. Such emissions can happen at any time and are not always associated with significant changes in seismicity. Ash clouds and fallout from these events are not likely to extend beyond the caldera rim, but could pose a hazard to people and low-flying aircraft in the vicinity of the active cone. There are no indications that a larger eruption is imminent.
OTHER ALASKA VOLCANOES
Seismic activity is monitored in real time at 30 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. Wrangell, Spurr, Redoubt, Iliamna, Snowy, Griggs, Katmai, Novarupta, Trident, Mageik, Martin, Peulik, Ukinrek Maars, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin, Fisher, Westdahl, Akutan, Makushin, Okmok, Korovin, Great Sitkin, Kanaga, Tanaga, and Gareloi volcanoes are in color code GREEN. 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.
ABBREVIATED COLOR CODE KEY
(contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected at any time
VOLCANO INFORMATION ON THE INTERNET: http://www.avo.alaska.edu
RECORDING ON THE STATUS OF ALASKA'S VOLCANOES (907) 786-7478
Tom Murray, Scientist-in-Charge, USGS
firstname.lastname@example.org (907) 786-7497
Steve McNutt, Acting Coordinating Scientist, UAF-GI
email@example.com (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.