In the Caucasus chemical denudation makes up 34 million tons each year and its annual layer is 38 microns. In the basin of the Black Sea It is most intensive — 130 microns — due to the solubility of mountain rocks and the abundance of atmospheric precipitation. To the east the chemical denudation becomes weaker. Denudation according to the suspended alluvium of rivers makes up 130 million tons, and the annual layer—150 microns. It is most intensive in the basins of Samur and Sulak — up to 3500 tons per sq. km. The involved alluvium makes from 10 to 50 per cent of the suspended one.