Orogenesis mechanism in Transbaikalian and southern Far East regions 15-23

Abstract

The history of topographic evolution is analysed with reference to SW Transbaikalian region, Sikhote-Alin and Tukuringra-Iagdy ridges. Geological and geophysical data obtained give no ground for considering of the regional orogenesis within the frame of mobilistic theory. The main cause of the orogenesis here is thought to be subvertical migration of the upper mantle matter along deep fractures, granitisation and the earthcrust density reduction due to heat and mass transfer, thickening and deepening of «mountain roots» which result in isostatic uplift of the mountains. However the author thinks it real enough the two lithospheric plates (geoblocks) to have collided in the Mongol-Okhotsk sutural zone; Tukuringra-Jagdy horst was formed as Amur and Aldan-Stanovoi geoblocks were brought together.