Extension in the Baikal Rift and the Depth of Basalt Magma Generation

摘要

It is considered that the opening of the Baikal rift system occurred as a result of counterclockwise rotation of the Amur microplate relative to stable Siberian Craton [1]. The pole of rotation is located on the northeastern termination of the rift system in the area of the Chara depression [1,2] (Fig. 1). According to gravimetrical data, it was established that the value of the extension increases linearly from the pole of rotation towards the South Baikal depression [2]. The recent data of the seismic profiling across the South Baikal depression show that under this depression the rise of the Moho boundary is absent.