Mutnovsky is a composite stratovolcano with a large twin crater at its summit. These craters have crater lakes in them and very active fumaroles. Pumice beds, cones and lava flows can be found on the slopes of these craters. Explosive eruptions producing ash occurred in 1945-52 and then again in 1960. This volcano also goes by the names of Mutnaia sopka, Povorotnaia sopka and Sopka Mutnovskaia. It is thought that this volcano possibly located in an old ruined caldera with a diameter of about 9 km. The mountain itself could have been formed by two merging cones. Originally there had been one stratovolcano then later on a second emerged on the northwestern slope of the first. Over time the caldera of the first volcano got filled with ejecta from the second cone. A 3 x 1.5 km pear shaped crater exists at the summit of Mutnovsky, here one can find its two lakes and steam vents that emit huge quantities of volcanic gases.
Sources of Information:
Sviatolovsky, A. E. 1959 Atlas of Volcanoes of the Soviet Union, USSR Academy of Sciences, Moscow USSR. p167.
Vlodavetz V.I., Piip B. I. 1959 Kamchatka and Continental Areas of Asia. Catalog of Active Volcanoes of the World, Rome IAVCEI, 8: p16-17.
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