The role of volcanism in the development of the Japan,Okhotsk, and Philippine marginal seas

Newly obtained petrological and geochemical data on Late Mesozoic-Cenozoic volcanic complexes in the Japan, Okhotsk, and Philippine marginal seas of the Pacific Ocean made it possible to specify the types and characteristics of various stages of volcanism in the seas, trace the evolutionary history of the volcanic processes, and identify the geodynamic environments in which the deep-sea basins were formed, as well as to distinguish inherent features in the evolution of marginal seas in the continent-ocean transition zone in the Central Asian sector of the Pacific Ocean. These features imply that the processes that formed this zone in the region were similar. Significant differences revealed between the zones in the region were predetermined, first of all, by the different types of the Earth’s crust that was involved in the major tectonic-magmatic processes and participated in the generation of the magmatic melts.