Local name(s): Tolbachik, Plosky Tolbachik (shield), Ostry Tolbachik (stratovolcano)
Largest recorded eruption: VEI 4 in 1975
Last eruption: August 2013
Tolbachik is a basaltic volcanic massif lying at the southern end of the Kliuchevskoi group in Kamchatka, Russia. It comprises two overlapping cones: Plosky Tolbachik, a Holocene shield volcano extending to 3 km in diameter; and the older (Pliestocene) Ostry Tolbachik, a sharp-topped stratovolcano reaching some 3,700 m in height. The summit of the shield volcano formed ~6,500 years ago and is associated with a major sector collapse of Ostry Tolbachik; however, its most voluminous historic eruption occurred in 1975 when vents situated along a 28 km-long fissure erupted ~ 1km3 of basaltic material. Plosky Tolbachik erupted in a similar fashion in 2012-2013.