USGS Volcano Hazards Program Volcano Update


AVO update page and observatory web site


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 (http://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.

Update in Common Alerting Protocol (CAP) format