ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Tuesday, June 25, 2013, 12:33 PM AKDT (Tuesday, June 25, 2013, 20:33 UTC)

PAVLOF VOLCANO (VNUM #312030)
55°25'2" N 161°53'37" W, Summit Elevation 8261 ft (2518 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Vigorous eruptive activity indicated by a distinct increase in seismicity beginning around 6:50 UTC (22:50 AKDT) last evening is continuing. The level of seismicity for the past 11-12 hours has been the strongest seismic activity detected so far during the 2013 eruption of Pavlof Volcano. The seismicity is characterized by intense, continuous tremor and intermittent small explosions that are likely associated with lava fountaining and ash production.

Satellite data and pilot reports indicate a distinct plume extending to the west from the volcano at least and rising as high as 27,000 to 28,000 feet above sea level. Strong thermal signals at the summit have been evident in satellite imagery. This morning, AVO received a report of trace ash fall on the community of King Cove about 30 miles southwest of the volcano.

At this level of unrest it is likely that lava fountaining and ash emission are occurring. Lava fountaining is likely producing spatter-fed lava flows that are descending the flanks of the volcano over ice and snow and could be producing substantial steam plumes. These plumes probably contain variable amounts of ash. At the level of unrest observed over the past 11-12 hours, the volcanic plume has not been particularly ash rich; however, this could change if the character of the eruption changes and it remains possible for more robust ash plumes to be generated at any time. AVO is monitoring the eruption closely and will issue further information as it becomes available.




VENIAMINOF VOLCANO (VNUM #312070)
56°11'52" N 159°23'35" W, Summit Elevation 8225 ft (2507 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Volcanic tremor continues to be detected in seismic data indicating that the eruption of Veniaminof Volcano continues. Satellite images obtained over the past 24 hours show elevated surface temperatures at the intracaldera cone. Web camera images from Perryville show a small light-colored plume rising above the intracaldera cone to just above the rim of the caldera at about 8,200 feet above sea level.

It is possible for activity at Veniaminof Volcano to increase above its current level at any time and more vigorous ash emissions may result. Sustained periods of volcanic tremor may correspond with continuous ash emission which may not be detected in satellite data, especially if ash plumes remain below 15,000 to 20,000 feet above sea level. Brief bursts of ash emission and small explosions with ash fall limited to areas on the flanks of the volcano are likely to occur while the volcano is at its current level of unrest. A larger explosive episode and associated ash emission is not expected at the current level of unrest; however, this remains possible and would be evident in seismic and satellite data.

CLEVELAND VOLCANO (VNUM #311240)
52°49'20" N 169°56'42" W, Summit Elevation 5676 ft (1730 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

No elevated surface temperatures were observed in satellite images over the past 24 hours. AVO has received no other reports of activity at the volcano.

Sudden explosions of blocks and ash are possible with little or no warning and ash clouds, if produced, could exceed 20,000 feet above sea level. If a large ash-producing event occurs, nearby seismic, infrasound, or volcanic lightning networks should alert AVO staff. However, for some events, detection may not be possible for several hours. Cleveland volcano does not have a local seismic network and is monitored using only distant seismic and infrasound instruments and satellite data.







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

Jessica Larsen, Acting Coordinating Scientist, UAFGI
jflarsen@alaska.edu (907) 474-7992

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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