Printer friendly versionALASKA VOLCANO OBSERVATORY INFORMATION STATEMENTThursday, April 26, 2007 10:07 AM AKDT (Thursday, April 26, 2007 18:07 UTC)VENIAMINOF VOLCANO
56°11'52" N 159°23'35" W, Summit Elevation 8225 ft (2507 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN
Previous Aviation Color Code: YELLOW
Previous Volcanic Activity Alert Level: Advisory
Background-level, intermittent seismic activity has continued at Veniaminof Volcano for several months. Although cloudy conditions have prevented consistent views of the volcano by satellite, web camera, and ground observers over the past several months, periodic views have shown steaming from the instracaldera cone, but no other activity. AVO has received no reports of recent ash emissions from pilots or observers on the ground. The last ash-laden plume visible in web camera images was observed on November 2, 2006. The last likely thermal anomaly in satellite images was observed on July 5, 2006 and the last ash signal seen in satellite images was observed on March 16, 2006. Based on the historic behavior of Veniaminof, the emission of steam from the intracaldera cone is typical behavior and minor low-level ash emissions may return at any time with little or no warning. The Aviation Color Code for Mount Veniaminof Volcano is downgraded from yellow to GREEN
and the Volcanic Activity Alert Level from advisory to NORMAL.
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, and early November 2006. 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.