Sedimentary (oil and gas bearing and potentially oil and gas bearing) systems of the Sea of Okhotsk region: geodynamic arrangement

Multidisciplinary approach to 3D geodynamic differentiation of the Cenozoic sedimentary cover of the Sea of Okhotsk Petroleum Province using the sequence analysis allowed distinguishing sedimentary cyclothems forming the independent structural and material associations, and also revealing their relationships with the global and regional tectonic and eustatic events, which in turn are dependent on the global Earth pulsations having a form of plume liberation of gas from subsurface. In the early stages of plume- and rift-related Paleocene-Early Miocene processes, the horst-graben infrastructure of paleotaphrogens; they were the largest structural elements of the region, which were later transformed into the major oil and gas bearing and potentially oil and gas bearing subprovinces. In the late rift-related and post-rift time, the Later Oligocene-Quaternary subplate cover was formed, which superposes the Paleogene infrastructure; it is represented by the transgressive-regressive sequences with a structure dictated by the eustatic events. The initial stages of their formation are associated with the considerable Sea Level rises, subsynchronous water depth deeping in the region, and accumulation of predominantly argillaceous formations (regional impermeables). In the period of lowering the water table, the regressive reservoir cyclothems are formed. Endodrainage structures created by the rift-related processes and canalizing deep fluid flows are activated at the interfaces of cycles in the form of the short-durable structural rearrangements, which transform the cyclothems into independent structural and stratigraphic (oil and gas bearing and potentially oil and gas bearing) sequences. In Pliocene-Quaternary cycles closing the geodynamic evolution of the region, the sedimentary cyclothems are finally transformed into oil-bearing