Published on 24 May 2016
Southern Baikal region is one of the areas in Russia prone to mudflow hazard. High natural potential for mudflow formation in the southern Baikal region is determined by a combination of the following factors: relatively high disintegration of bedrock and their physico-mechanical and physico-chemical properties in relation to the weathering agents, sufficient volume of friable fragmental material, considerably steep thalwegs, heat and moisture conditions, as well as high seismotectonic activity of the area. Geologically the area is marked by the igneous and metamorphic rocks including granitoids, gneisses, schists, marbles, basalts, sandstones, clays, which have various resistance to weathering agents and particle size distribution of the weathering products. Alluvial-proluvial sediments are one of the main sources of the solid mudflow phase formation, accounting for up to 50–80% of their total volume. Geomorphological conditions of the southern shore of Lake Baikal contribute to landslide development due to intensive erosional dissection of the northern slope of the Khamar-Daban ridge, with in average one river and two mudflow hazardous blind creeks per every 3 km of the shore. Large thalweg angles are conditioned by relative elevation of the estuaries over the river sources. Among climatic factors determining mudflow formation, precipitation is a predominant one. Regional proportion of rainfall per year is 70% and more. For instance, in 1934 and 1971 their total exceeded the mean yearly rate by almost 20%. The high seismotectonic activity of modern geodynamics of the Baikal Rift Zone, including the south of the Baikal region, stimulates development of mudflow processes. Among the measures aimed at reducing the mudflow hazard marked technical, ameliorative, organizational and economic. The best results are obtained with a combination of protective measures, in particular technical and ameliorative. Their implementation will minimize the economic and social damage, and the elimination of debris flow and flood risk in the developed areas of the south of the Baikal region.
Categories: Articles, Geo-ecological,-Recreational-and-Biomedical-Issues-of-SDMT
Tags: сели, оползни, тектоника, сейсмичность, геологические опасности, паводки, климатические осадки, инженерные сооружения, защита
ISSN 1998-4502 (Print) ISSN 2499-975Х (Online)