EARTH’S CRYOSPHERE SCIENTIFIC JOURNAL Kriosfera Zemli, 2018, vol. XXII, No. 3, pp. 3–15 http://www.izdatgeo.ru REGIONAL PROBLEMS OF EARTH’S CRYOLOGY DOI: 10.21782/EC2541-9994-2018-3(3-15) THE PHENOMENON OF GEOCRYOLOGICAL CONDITIONS IN THE EASTERN PART OF THE OLEKMACHARA PLATEAU S.N. Buldovich, E.N. Ospennikov, V.Z. Khilimonyuk Lomonosov Moscow State University, Faculty of Geology, 1, Leninskie Gory, Moscow, 119991, Russia;
[email protected] The paper discusses results of the study of geocryological (permafrost) conditions in the eastern part of the Olekma-Chara Plateau at the watershed divide of the Tokko River and its tributary, the Choruoda River, carried out within the fi eld study of the sites of mineral showings (deposits), whose permafrost conditions are extremely contrasting. The combined impact of hydrogeological factors acting in the middle altitude environ- ment is found to be largely responsible for the unique permafrost conditions in the study area. Olekma-Chara Plateau, geocryological conditions, hydrological conditions, permafrost, annual average soil temperatures, geocryological processes INTRODUCTION The study area, located in the southwest of the Moscow State University, which conducted a compre- Republic of Sakha (Yakutia) and subsumed into the hensive permafrost-hydrogeological and permafrost- eastern part of the Olekma-Chara Plateau, is under- engineering geological survey within the Aldan-Timp- lain by permafrost which had been largely underex- ton interfl uve area. Later, in 1973–1985, this expedi- plored until the middle of the twentieth century, with tion conducted medium-scale surveys (1:50 000 and the information about it ranging from sketchy (i.e. 1:200 000) in the areas of coal deposits within the derived from results of comprehensive geological- Chulman Plateau, southern Yakutia [Kudryavtsev, geophysical expeditions) to unavailable.