The Pavlof eruption that began Nov. 12 intensified Saturday to Aviation Code Red for ash emissions observed to over 9,100 m and Volcano Alert Level to Warning. AVO Pavlof page with links to webicorders can be found at the following link. http://www.avo.alaska.edu/activity/Pavlof.php
Mount Pavlof is part of a multiple volcanoes which comprise the Emmons Lake Volcanic Complex that sits some 950 km southwest from Anchorage. Emmons Lake has multiple stratovolcano cones, embedded calderas, the largest of which measures some 11 x 18 km in diameter. The last caldera forming eruption from the complex is thought to be some 10,000 years ago. http://pubs.usgs.gov/sir/2006/5248/
Pavlof itself measures some 2,500 m tall and is next to a smaller cone called Pavlof Sister and a cone that shares its edifice called Little Pavlof. It is the most active eruptive center of the complex, with multiple eruptions observed since the early 18th Century. http://www.avo.alaska.edu/images/image.php?id=22963
These eruptions range from Strombolian in nature with lava flows down the flanks to more powerful eruptions putting ash on surrounding communities of Sand Point and Cold Bay. Both communities are currently under a watch for ashfall. Sand Point is some 90 km east of Pavlof. Historically observed eruptions have measured in the VEI 2 – 3 range. Pavlof is one of the most active volcanoes in the Aleutians. http://www.avo.alaska.edu/activity/ash3d/cloud_height.php?vid=ak210
The Alaska Volcano Observatory’s primary mission is aviation safety on the Great Circle airway overflying the Aleutian Islands. http://www.adn.com/article/20141115/cold-bay-sand-point-residents-could-see-ashfall-pavlof
I will do an extended post on the Emmons Lake Volcanic Complex in the days and weeks to come. Cheers –
Update: as of this writing, (1045 L AST), it appears that the large eruption of Saturday has subsided for the time being. Cheers –
Update 2: Link to the CIMSS Satellite Blog courtesy of Sherine France. It shows the progression of Saturday’s plume in multiple wavelengths / satellite photos. Many thanks, Sherine.