Natural radionuclides in rocks and soils of the high-mountain regions of the Great Caucasus

The results of the radioecological survey in the high-mountain regions of the Great Caucasus at the heights from 2200 to 3800 m a.s.l. are considered. This survey encompassed the territories of Dagestan, Azerbaijan, Georgia, Chechnya, Northern Ossetia-Alania, Kabardino-Balkaria, Karachay-Cherkessia, and the Stavropol and Krasnodar regions. The natural ?? background radiation in the studied regions is subjected to considerable fluctuations and varies from 6 to 40 ??R/h. The major regularities of the migration of natural radionuclides ²³⁸U, ²³²Th, ²²⁶Ra, and ⁴⁰K in soils in dependence on the particular environmental conditions (the initial concentration of the radionuclides in the parent material; the intensity of pedogenesis; the intensity of the vertical and horizontal migration; and the geographic, climatic, and landscape-geochemical factors) are discussed.