The territory of the Baikal land is specific because of its complex engineering-geological conditions. Its geological structure is made up of formations different in their composition and age. There are carbonate and silicate strongly dislocated and metamorphosed Archaean and Proterozoian rocks, as well as platformic terrigenous and carbonate cemented and altered sediments, often crumpled into narrow linear folds of north-eastern extension. The igneous rocks are represented by intrusive and effusive differences. Granites of different composition and structure are widespread among them over the southern and north-eastern coast. The edge parts of the Baikal hollow are filled with Quaternary lake, river, proluvial and glacial formations.
The peculiarities of the rocks collecting qualities influence the fact that two types of hydrological reservoirs of different depths of bedding have been singled out in the Baikal land – they are basins of the underground stratum waters and massives of fissure and fissure-vein waters.
High seismic activity of the Baikal land creates special difficulties for all kinds of construction and needs making special maps of division into seismic microdistricts.
The Baikal land is included into the region of insular and compact spread of long-term permafrost. The thickness of the frozen ground on the coast is not more than 10 m, and its temperature is not lower than –0.2…-0.3°. The islands of melted ground are concentrated near the river-beds, on the slopes of the southern and northern expositions, sometimes on the watersheds. Thermokarst, ice crusts, hydrolaccolites or ground flatulence are widespread permafrost phenomena. Ice crusts sometimes formed under engineering constructions are especially dangerous. During construction of railways and car roads changes in the ground waters and temperatures often increase the flatulence and formation of ice crusts and need special measures to insure the firmness of the constructions.
Massive mud-torrents are recorded from time to time on the south-eastern and north-western shores of Lake Baikal. It is necessary to protect all the threatened regions.