ALASKA VOLCANO OBSERVATORY WEEKLY UPDATE
Friday, June 14, 2013 1:30 PM AKDT (Friday, June 14, 2013 21:30 UTC)


VENIAMINOF VOLCANO (CAVW #1102-07-)
56°11'52" N 159°23'35" W, Summit Elevation 8225 ft (2507 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Mount Veniaminof volcano began erupting on Thursday morning, June 13 following several days of increasing seismicity. On Saturday, June 8, AVO elevated the Aviation Color Code to YELLOW and the Volcano Alert Level to Advisory in response to increasing levels of seismic tremor recorded beneath the volcano. Nothing unusual was observed in satellite imagery. An FAA web camera in Perryville recorded minor steam with possible ash emissions rising from the intracaldera cinder cone on Monday, June 10. Seismic tremor continued to gradually but steadily increase over the next several days. On the morning of Thursday, June 13, intense elevated surface temperatures were recorded in satellite images at the intracaldera cinder cone indicating that an eruption was likely underway. AVO raised the Color Code/Alert Level to ORANGE/WATCH. Late that evening, at 11:23 pm AKDT (07:23 UTC on June 14), a pilot observed an ash plume up to about 12,000 ft above sea level and a lava flow issuing from the intracaldera cinder cone. Residents in Perryville and Port Moller also reported observing the ash emissions at about 11:30 pm AKDT (07:30 UTC on June 14). Observers located west of the volcano reported that no ash was issuing from the intracaldera cinder cone this morning; however ash emission could resume abruptly at any time. Refer to the NWS Alaska Aviation Weather Unit ( [link to aawu.arh.noaa.gov] for updates on SIGMETs related to ash emissions.

Recent satellite images show intense elevated surface temperatures at the intracaldera cinder cone consistent with the pilot report of the presence of lava. Volcanic tremor continues. The seismic network at Veniaminof is not fully functional compared to that operating during the last eruption (2005), so the accuracy with which we can interpret ongoing seismicity is diminished.

Recent eruptions of Veniaminof volcano have all occurred from vents located on the intracaldera cinder cone and were characterized by brief bursts of ash emission and small explosions. Ash plumes associated with this type of activity are typically diffuse and generally do not reach more than 20,000 feet above sea level. Ash fallout is typically limited to the flanks of the volcano. Minor emissions of steam and ash may persist for for weeks to months.

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 cinder 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.
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[link to www.avo.alaska.edu]

Mount Veniaminof
From Wikipedia, the free encyclopedia
Mount Veniaminof

Steam rising from the intracaldera cinder cone at Veniaminof volcano in the waning stages of the 1983 to 1984 eruption.
Elevation 8,225 ft (2,507 m)
Prominence 8,199 ft (2,499 m)[1]
Listing Ultra
Location
Location Alaska Peninsula National Wildlife Refuge, Alaska, U.S.
Range Aleutian Range
Coordinates 56°11′53″N 159°23′27″W
Topo map USGS Chignik A-5
Geology
Type Stratovolcano with a summit caldera
Volcanic arc/belt Aleutian Arc
Last eruption February 22, 2008[2]
U.S. National Natural Landmark
Designated: 1967
Mount Veniaminof is an active stratovolcano located on the Alaska Peninsula. The Alaska Volcano Observatory currently rates Veniaminof as Aviation Color Code ORANGE and Volcano Alert Level WATCH as of June 13, 2013, 2030 (UTC) after satellite observations of elevated temperature at its summit.[3] The mountain was named after Ioann (Ivan Popov) Veniaminov (1797–1879), a Russian Orthodox missionary priest (and later a prominent bishop in Russia) whose writings on the Aleut language and ethnology are still standard references. He is a saint of the Orthodox Church, known as Saint Innocent for the monastic name he used in later life.
The volcano was the site of a colossal (VEI 6) eruption around 1750 BC. This eruption left a large caldera. In modern times the volcano has had numerous small eruptions (over ten of them since 1930); these are located at a cinder cone in the middle of the caldera.
Veniaminof has one of the highest elevations of Alaskan volcanoes. Partly for this reason, it is covered by a glacier that fills most of the caldera. Because of the glacier and the caldera walls, there is the possibility of a major flood from a future glacier run.
[link to en.wikipedia.org]