Geomorphology of the Okhotsk slope of the Iturup Island (Big Kuril Ridge)

Abstract

New data are presented on the western slope of the Big Kuril Ridge (facing the Sea of Okhotsk) near the Iturup Island. Morphology of 8 submarine volcanoes is discussed in detail, the volcanoes with pronounced flat tors are suggested to classify as guyots of island arcs. They are supposed to form completely or partly above the sea level and later to submerge, their tops being eroded by waves.

Hypsometric analysis of planation surfaces on the volcanoes indicates recent regional subsidence of the sea floor west of the Big Kuril Ridge and therefore a relatively young age of the Southern Okhotsk deep-sea basin.