M7.4 - EAST OF THE KURIL ISLANDS

Tectonic Summary

The Kuril Islands earthquake of January 15th, 2009 occurred as a result of thrust faulting within the Pacific plate. The event occurred near the outer-rise of the Pacific plate about 30 km to the east of where the Pacific plate subducts beneath the Okhotsk plate. In this region, the Pacific plate moves northwest with respect to the Okhotsk plate with a velocity of about 90 mm/yr.

Large and great earthquakes are not uncommon in this region. The location of this event is approximately 90 km to the northeast of the Mw 8.1 outer rise earthquake of January 13th 2007, which occurred as a result of normal faulting near the Pacific plate outer-rise. On November 15th 2006, an Mw 8.3 subduction-related thrust earthquake occurred approximately 160km to the southwest.