Subsidence of the Japan Sea: stratigraphic evidence from ODP sites and onshore sections

Abstract

Abundant geologic, geophysical, and paleontologic evidence from ODP drilling in the Japan Sea and from adjacent continental and insular areas demonstrates that the sea has evolved rapidly over the past 32 my and is now in an early stage of compressive destruction. Stratigraphic, geochronologic, and paleobathymetric data derived from ODP Site 794, 795, 796, 797, 798, and 799, offshore exploration wells, and uplifted and deformed Neogene stratigraphic sections exposed on the Korean Peninsula and the islands of Honshu, Hokkaido, and Sakhalin were used to analyze the timing and patterns of backarc subsidence characterizing each stage in the evolution of the Japan Sea. An extensional tectonic regime and subsidence dominate backarc evolution ca 32 Ma to 10 Ma at which time regional uplift was initiated marking the onset of a compressional regime that continues to the present. -from Author