The Kuril Arc and Kuril Basin

Relationship between Rotation of Backarc Plate and Backarc Spreading

Abstract

The Kuril basin was formed by back-arc spreading in Oligo-Miocene time which is deduced from bottom depth, heat flow and geological data in and around the basin. The b sin has a shape of fan which diminishes northeastward and closes just southwestern end of Kamchatka Peninsula.
The fan shape strongly suggests that the basin was formed by the rotation of backarc plate (the Okhotsk Plate) around a relative rotation pole located between the Kuril Basin and Kamchatka Peninsula. Geology around the Sea of Okhotsk indicates that the clockwise rotation of the Okhotsk Plate and the fan spreading of the Kuril Basin concurrently took place in Oligo-Miocene time.