Morphometric and geomOrphological analysis of drainage network in the central Baikalian rift zone

Abstract

The drainage network within the region- is largely controlled by general structural pattern. The riftogenesis preconditioned two types of river valleys, which are trunk valleys and «feather» valleys. Trunk valleys drain riot depressions, the drainage boasins show a typical asymmetry of Baikalian type, left and right sides of a basin differing in and in tributaries structure. The trunk valleys evolution proceeds against the inherited subsidence of the basins floor. Morphometric analysis permits to outline individual blocks of the basement and to establish their relative altimetric position. «Feather» valleys develop under conditions of differentiated movements of crustal blocks. Rivers of this kind also show differences depending on their position with respect to the rift zone axis, which indicates some differences in the geomorphic evolution of the areas.