Diky Greben is an extrusion made of andesite and dacite. It is a dome that was formed along fissures from mostly dacitic lava. Cracks on the dome hold several lakes. Large outbursts of pumice also occurred at Diky Greben, and very thick pumice flows exist in the area.
More information on Diky Greben (in Russian)
Sources of Information:
Erlich, E.N. and Melekestsev, I.V., "Quaternary Acid Volcanism of Kamchatka," Modern Geology, v. 3, pp. 183-193, 1972.