Printer friendly versionALASKA VOLCANO OBSERVATORY
Current Status Report
Friday, September 14, 2007 12:40 PM AKDT (2040 UTC)
55°24'57" N161°53'24" W, Summit Elevation 8261 ft (2518 m)
Current Aviation Color Code: ORANGE
Current Volcano Alert Level: Watch
The eruption of Pavlof continues. Seismicity remains low as reported today in our Weekly Update (http://www.avo.alaska.edu/activity/avoreport.php?view=update). Clouds obscured views of the volcano by satellite and web camera today. The decrease in seismicity may be only a lull in the current eruption. Typical eruptions at Pavlof are characterized by periods of dimished activity interspersed with the periods of renewed eruptive activity. Renewed activity could begin at any time with little seismic warning.
If activity should increase in intensity, larger ash clouds that could affect higher-flying aircraft may be produced. The most immediate ground hazard in the vicinity of the volcano includes light ash fall on nearby communities. Previous historical eruptions from Pavlof caused only a few millimeters (about 1/10th of an inch) of ash to fall on King Cove, Nelson Lagoon, Cold Bay, and Sand Point. Mudflows in drainages from the flanks of the volcano, and lava flows and avalanching of hot debris on the upper reaches of the volcano are also of concern in the uninhabited areas around the volcano. Satellite and seismic data and eyewitness observations suggest most of the surface lava activity is occurring on the southeast sector of the steep-sided volcano; this suggests that the Pacific Ocean side of the volcano is at most risk from avalanching hot debris.
At this time, we expect this eruption to follow the pattern of previous eruptions. The last eruption of Pavlof began in September 1996 and consisted of a several-month-long series of ash explosions, lava-fountaining, and lava-flow production. Ash clouds reached as high as 30,000 ft asl on one occasion. However, most ash clouds were below 20,000 ft asl. Prior to 1996, Pavlof erupted in 1986 sending ash as high as 49,000 ft asl on at least one occasion. A hazard assessment for Pavlof and the Emmons Lake volcanic center is available on the web at http://www.avo.alaska.edu/pdfs/SIR2006-5248.pdf
52°49'20" N169°56'42" W, Summit Elevation 5676 ft (1730 m)
Current Aviation Color Code: YELLOW
Current Volcano Alert Level: Advisory
A partly clear satellite image from last night showed steaming and new snow at the summit of Cleveland. The temperature of the thermal anomaly in the crater has decreased. These data are consistent with our decision to decrease the aviation color code to yellow last week.
AVO continues to monitor the volcano closely with satellite imagery as weather allows. The lack of a real-time seismic network at Cleveland means that AVO is unable to track local earthquake activity related to volcanic unrest. Short-lived explosions of ash that could exceed 20,000 ft above sea level can occur without warning and may go undetected on satellite imagery.
VOLCANO INFORMATION ON THE INTERNET: http://www.avo.alaska.edu
RECORDING ON THE STATUS OF ALASKA'S VOLCANOES (907) 786-7478
John Power, Acting Scientist-in-Charge, USGS
firstname.lastname@example.org (907) 786-7497
Steve McNutt, Coordinating Scientist, UAF
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.