Below: Ash plume from the volcano caused by an eruption dated October 6th 2012.
Klyuchevskaya Sopka, the highest of all the Kamchatka volcanoes at 4,750m above sea level, has also been active recently. On the 25th January 2013 a strombolian eruption was recorded, featuring the expulsion of some incandescent cinders and low-energy ejection of lava bombs.
Below: A strombolian eruption
The Aleutian ocean trench to the west of Kamchatka is the ocean trench from this plate margin, and can be seen clearly on the location image (three above).
Composite volcanoes are common at subduction zones and are particularly explosive. There is however little danger to the nearest settlement Klyuchi which is 50km away and is so small it could evacuate quickly in the case of a large eruption.
Josh Long, 25/07/2013
Thomas Ruddell (supplement), 25/07/2013