Bolshya Ipelka, a is located on the same east-west tectonic line that
Opala is located on. This large volcanic caldera
surrounded by a ring-shaped ridge with steep inner walls and rocky outer
slopes. It is made up of the remains of a great volcano that has been
eroded and destroyed.
Some other volcanoes in this local area are: Mutnovsky, Asacha, and Opala.
Sources of Information:
Krijanovsky, N. 1934 Geological Society of America Bulletin, vol. 45 p.533.
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