Масштабы современной денудации Кавказа (на примере Северной Осетии)

Аннотация

A quantitative estimation of the present-day erosion at Northern Ossetia is given on the base of field observation, air photographs interpretation and son other data. Glacial denudation removes from the area of present-day glaciation (20 sq.km) 16 000 cum per year, avalanches carry out 9000 cu.m per year from 100 sq.km, rockfall accumulation on 5 sq.km is 800-1000 cu.m per year, rock talus moves 240-400 cu.m debris, the scarp front being 1 km long, mudflows remove 150 000 cu.m per year from 100 sq.km area, karst denudation rate is 26,8 cu.m per year, sheetwash value from arable slopes is 100 cu.m, from slopes with natural vegetation- 48 cu.m per year, mean value of gully erosion (calculated for one gully, catchment area being 20 sq.km) is 3000 cu.m. Total erosion estimated from rivers solid discharge is proved to be erroneous, river load being only 40-50% of the whole volume of eroded material.

Ratio of mean total specific intensity of exogenous processes (1,8 Mm per year) to recent tectonic movements rate is 1:12 to 1:14 for high mountains, 1:6 to 1:8 for middle mountains, 1:2 to 1:4 for low mountains.

The introduced technique of calculation of recent erosion general volume can be used for the same calculations at other mountain regions.