Hitokappu Volcano Group [Bogatyr Ridge]

Geography & Climate

Hitokappu Volcano Group [Bogatyr Ridge] is located in Japan - administered by Russia, within the Kuril Volcanic Arc of the broader Northwestern Pacific Volcanic Regions. Situated at 44.86° N, 147.40° E in the Northern Hemisphere, the volcano lies within a temperate climate zone. With a summit elevation of 1,610 meters above sea level, Hitokappu Volcano Group [Bogatyr Ridge] is a moderately sized peak that remains accessible to hikers and researchers for much of the year. The volcanic landform is characterized as a cluster, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Hitokappu Volcano Group [Bogatyr Ridge] sits in a subduction zone, where one tectonic plate dives beneath another, creating intense heat and pressure that generates magma. Subduction zones are responsible for many of the world's most explosive volcanoes and deadliest eruptions. For communities in Japan - administered by Russia near Hitokappu Volcano Group [Bogatyr Ridge], this tectonic setting means the volcano is capable of producing powerful explosive eruptions, pyroclastic flows, and lahars that can threaten populated areas within tens of kilometers of the summit. The dominant rock type is andesite / basaltic andesite, a dark, fine-grained volcanic rock that forms from rapidly cooling, low-viscosity lava. Basaltic eruptions tend to be less explosive and produce fluid lava flows that can travel long distances. While less immediately dangerous than explosive eruptions, basaltic lava flows can destroy structures and infrastructure in their path, and volcanic gases released during these eruptions can affect air quality over a wide area.

GVP Reference Summary

The Hitokappu Volcano Group [Bogatyr Ridge] on Iturup Island in the southern Kuriles consists of a cluster of late-Pleistocene to Holocene cones and craters extending ~14 km NE-SW. The basaltic andesite to andesitic Nishihitokappuyama (also known as Stokap) stratovolcano at the SW end of the ridge appears to be the location of the most recent eruptions, with a summit area that includes 8-10 cones and explosion craters, the largest of which contains a lake. The volcanic chain was constructed over a high Pleistocene base, whose glaciated surface is covered by lava flows from Nishihitokappuyama that reach to both the Pacific Ocean and the Sea of Okhotsk. JMA (2013) does not include this as a Holocene volcano.

— Smithsonian Institution, Global Volcanism Program