The results of one-dimensional inversion of generalized curves of magneto-telluric and magneto-variational soundings in south-western region of the East European platform are shown. Existence of a conductive layer at depths exceeding 600 km is confirmed in large parts of Ukraine and Belarus. The resistance of upper mantle within the territory of Belarus at depths of 250-400 km is about 2 times lesser than in Ukraine, and is about 20 Ohmm in Belarus and 50 Ohmm in Ukraine.
Purpose. Using new data on the deep structure of the crust and upper mantle and on paleogeodynamics, resulting from complex interpretation, a model of platectonic development of the transition zone northern coast of the Sea of Okhotsk – Eurasia was developed. To show the role of terrains in the development of Okhotsk microplate paleosubduction, appearance of Okhotsk-Chukchi volcanogenic belt and its latter closing.