Reconstruction of the Sakhalin marginal paleobasin by geological and petrochemical data

Abstract

The structural and compositional volcanosedimentary complexes and igneous rocks of the Sakhalin marginal paleobasin as well as the geodynamic setting were described. The Sakhalin marginal paleobasin was formed in Sakhalin Island and the adjacent water areas at the end of the Early Cretaceous-start of the Late Cretaceous. The paleobasin was a part of the Kula Plate separated from the ocean along with spreading zones and oceanic volcanic islands by the Sea of Okhotsk microcontinent and the Jurassic-Early Cretaceous Sheltinga volcanic island arc. The petrochemical features and geodynamic setting of the igneous rock formation testify to the fact that magma-generating tectonomagmatic structures of the epioceanic Sakhalin marginal paleobasin continued functioning after its isolation under intensive terrigenous sedimentation. The Sakhalin marginal paleobasin had a heterogeneous basement composed of oceanic and continental crust blocks of the Earth. The paleobasin completed its development in the Paleogene.