Role of damming by neotectonic movements in the sand deposition in valley systems of the Western Transbaikalian region

Abstract

The paper considers two points of view on the origin of the Pleistocene sand deposits infilling valley systems in the Western Transbaikalian region: 1) alluviation caused by the Baikal level rise due to increase in rainfall; 2) alluviation resulted from tectonic damming. Facts are supplied which contradict to the first opinion. A possible mechanism is suggested for alluviation in the Selenga drainage basin due to water ingression as a result of tectonic uplift of the ridges west of the Baikal depression. The author rejects the idea of paragenetic relation between the sand accumulation and mountain glaciation of the Baikal region.