The Oshima volcano is located in Japan, its primary volcano type is stratovolcano, and its last know eruption was in 1990. Its latitude is 34.724°N, its longitude is 139.394°E. It has an elevation of 2486 feet.
The Oshima volcano lies on the northernmost island of the Izu chain of islands, east of the Izu peninsula in the bay of Sagami. It is an uninhabited island about eight miles across form NNWW to SSEE and about 5 miles across from ENE to WSW.
The Oshima volcano is one of the most active volcanoes in the world, with an average eruption every 1-3 years, although it has not been active since 1990, an unusually long period of time. Its current status is dormant. Records of eruptions of Oshima date from ancient times. Oshima has erupted a total of 74 times.
A large caldera of about 2 to 2,5 miles sits on top of the volcano, with a central cone that is mostly flat, the Mihra-yama. A few dozen parasitic cones are situated inside the caldera. The volcano is made up of old olivine basalt, basalt lava and pyroclastic rocks.
The Oshima volcano has steep walls, except in the northeast as a result of lava flows.