The peculiarities of distribution of the bentonite-bearing silty-sandy-clayey sequence of the Tarusian stage are considered using materials of geological surveys of different years on scales 1:50 000 and 1:200 000 The result of generalization of all available materials was the construction of the schematic map of distribution of silty-sandy-clayey sediments of the Tarusian stage. It shows that the bentonite-bearing sediments are mainly confined to the west-northwestern part of the Carboniferous Plateau. The formation of this member is associated with the manifestation of a special hydrothermal-sedimentary type of lithogenesis in the northwestern part of the Russian Platform during the Serpukhov time.
