Bolshoy Semyachik Volcano is a complex volcanic edifice with a caldera 10 km in diameter. The formation of the caldera is associated with the removal of large masses of ignimbrites covering the vicinity of the volcano. Post-caldera formations fill the caldera and cover its eastern side. Among them, there are eight cone-shaped stratovolcanoes with a base diameter from 3-4 to 8-9 km: Zubchatka, Baraniy, Problematichny, Plosky, Kulakov, Popkov, Burlyashchiy, Central Semyachik. The space between them is occupied by numerous domes and cinder cones with lava flows. The age of the volcano is Lower-Middle Pleistocene.
References
Леонов В.Л., Гриб Е.Н. Вулкан Большой Семячик / Действующие вулканы Камчатки. В 2-х т. Т. 2. М.: Наука. 1991. С. 144-159. Леонов В.Л., Гриб Е.Н. Вулканический массив Большой Семячик, Камчатка: геологическое строение, структурная позиция // Вулканология и сейсмология. 2014. № 1. С. 3-19.  |
