ALASKA VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Friday, June 12, 2015, 11:44 AM AKDT (Friday, June 12, 2015, 19:44 UTC)

SHISHALDIN VOLCANO (VNUM #311360)
54°45'19" N 163°58'16" W, Summit Elevation 9373 ft (2857 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Low-level eruptive activity continues at Shishaldin Volcano. Elevated surface temperatures were observed in satellite data on a few occasions throughout the week, and clear web camera views of the volcano showed a persistent steam plume emanating from the summit. Continuous seismic tremor was detected by the local seismic network and this type of seismicity is generally indicative of low-level eruptive activity. The lack of fresh deposits on the upper part of the volcano or ash emissions detected in satellite or web camera views indicates that any eruptive products being generated are confined to the summit crater.

Shishaldin volcano, located near the center of Unimak Island in the eastern Aleutian Islands, is a spectacular symmetric cone with a base diameter of approximately 16 km (10 mi). A 200-m-wide (660 ft) funnel-shaped summit crater typically emits a steam plume and occasional small amounts of ash. Shishaldin is one of the most active volcanoes in the Aleutian volcanic arc, with at least 54 episodes of unrest including over 24 confirmed eruptions since 1775. Most eruptions are relatively small, although the April-May 1999 event generated an ash column that reached 45,000 ft above sea level.

OTHER ALASKA VOLCANOES

Other Alaska volcanoes show no signs of significant unrest: http://www.avo.alaska.edu/activity/

AVO scientists conduct daily checks of earthquake activity at all seismically-monitored volcanoes, examine web camera and satellite images for evidence of airborne ash and elevated surface temperatures, and consult other monitoring data as needed.

For definitions of Aviation Color Codes and Volcano Alert Levels, see: http://www.avo.alaska.edu/color_codes.php

FOR MORE INFORMATION ON ALASKA VOLCANOES: http://www.avo.alaska.edu

SUBSCRIBE TO VOLCANO ALERT MESSAGES by email: http://volcanoes.usgs.gov/vns/

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CONTACT INFORMATION:

Chris Waythomas, Acting Scientist-in-Charge, USGS
chris@usgs.gov (907) 786-7497

David Fee, Acting Coordinating Scientist, UAFGI
dfee@gi.alaska.edu (907) 322-4085

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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