Shallow gas hydrate occurrences and its related phenomena on the Sakhalincontinental slope, Russia

Abstract

The Sakhalin continental slope has been a well-known gas hydrate area since the first finding of gas hydrate in 1980's. This area belongs to the southernmost glacier sea in the northern hemisphere, where sea ice covers most of the area in the winter time. High organic carbon content in the sediment, cold sea environment, and active tectonic regime in the Sakhalin slope provide a very favorable condition for shallow gas hydrate accumulation and gas emission phenomena. Korean？Russian？Japanese international research expeditions (CHAOS, SSGH-I, SSGH-II projects) have been conducted from 2003 to 2015 to investigate gas hydrate occurrence and gas seepage activities on the Sakhalin continental slope, Russia.