ALASKA VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Friday, October 25, 2013, 11:30 AM AKDT (Friday, October 25, 2013, 19:30 UTC)

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

Seismic activity has been at low levels during the past week at Veniaminof. No unusual activity was observed in satellite images, and webcam images were mostly obscured by clouds. AVO has received no other reports of activity at the volcano.

It is possible that this is only a temporary waning of activity in the eruption that began in June 2013, and that more vigorous activity could resume. Pauses in eruptive activity such as this are not uncommon at this volcano. AVO will continue to monitor the volcano closely. AVO will continue to monitor the volcano closely.


Mount Veniaminof volcano is an andesitic stratovolcano with an ice-filled 10-km diameter summit caldera located on the Alaska Peninsula, 775 km (480 mi) southwest of Anchorage and 35 km (22 mi) north of Perryville. Veniaminof is one of the largest (~ 300 km3) and most active volcanic centers in the Aleutian Arc and has erupted at least 13 times in the past 200 years. Recent significant eruptions of the volcano occurred in 1993-95 and 2005. Both were moderate Strombolian eruptions producing intermittent low-level jets of incandescent lava fragments, and low-level emissions of steam and ash from the main intracaldera cone. During the 1993-95 activity, a small lava flow was extruded into the summit caldera ice field producing an ice pit. Minor ash-producing explosions occurred in 2002, 2004, early 2005, November 2006, and February 2008. Previous historical eruptions have produced ash plumes that reached 6,000 m (20,000 ft) above sea level and ash fallout that blanketed areas within about 40 km (25 mi) of the volcano.

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

Satellite and web camera images have been mostly obscured by clouds throughout the week. No new explosion signals were detected on distant infrasound (pressure sensor) networks during the last week and no eruptive activity has been observed in satellite data.

OTHER ALASKA VOLCANOES

Seismic activity is monitored in real time at 29 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, Mageik, Makushin, Martin, Novarupta, Okmok, Pavlof, Redoubt, Shishaldin, Snowy, Spurr, Tanaga, Trident, Ugashik-Peulik, Ukinrek Maars, and Westdahl 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 of these volcanoes.

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:

John Power, Scientist-in-Charge, USGS
jpower@usgs.gov (907) 786-7497

Jeff Freymueller Coordinating Scientist, UAFGI
jeff.freymueller@gi.alaska.edu (907) 378-7556

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.

---