In plan the Island has an oval shape measuring 6 X 13 km and an area of 62 square kilometers, strongly elongated in the meridional direction. The stratovolcano cone is located in the middle of the Island; it almost completely fills the ancient caldera. In its destroyed crater are two Holocene cones. The cone Zapadny is the highest point of the Island (956 m); at its top, a shallow crater with a size of 75 x 120 m has been preserved. Numerous lava flows descend from the crater in a westerly direction. The active cone Vostochny has an explosive crater more than 500 m wide, open in the form of an amphitheater to the southeast. Light, altered rocks stretch from the crater to the seashore on a wide front. A powerful flow of very fresh lava descends along the western slope of the cone. Older lava flows descend east and northeast to the ocean. The rocks of the volcano are two-pyroxene andesibasalts and andesites.
References
Горшков Г.С. Вулканизм Курильской островной дуги / Отв. ред. Рудич К.Н. М.: Наука. 1967. 288 с.  Горшков Г.С. Действующие вулканы Курильской островной дуги / Молодой вулканизм СССР. Труды Лаборатории вулканологии АН СССР.. М.: Изд-во АН СССР. 1958. Вып. 13. С. 5-70. Горшков Г.С. Каталог действующих вулканов Курильских островов // Бюллетень вулканологических станций. 1957. № 25. С. 96-178. |
