Lithogeochemical characteristics of the Yaksha formation (Western Transbaikalia)

The article presents the results of lithogeochemical studies of terrigenous rocks of the Yaksha formation. The Yaksha formation belongs to the Late Devonian, composed of terrigenous-carbonate rocks and is divided into two components. The object of geological exploration is located in the Bauntovsky district of the Republic of Buryatia. In regional terms, it is located on the sheet area GGK-200/2 occupying the central and northern parts of the Vitim plateau. [7] The lower Yaksha subformation is substantially carbonate, the upper Yaksha subformation is flyschoid terrigenous. According to the petrochemical characterization, the rocks of the Yaksha Formation are graywackes. According to the chemical composition, terrigenous rocks of the Lower Yaksha carbonate subformation are classified as normotitanic and supertitanium normosiallites, rocks of the Upper Yaksha subformation are classified as normotitanic normosyllites,. According to geochemical data, the Lower Yaksha subformation was formed in the conditions of a shallow carbonate shelf with vigorous water movements, the Upper Yaksha subformation was formed in deeper conditions of the open terrigenous shelf. The sources of rock drift could be the closely located uplifts of the Late Precambrian foundation, composed of Upper Riphean island-arc complexes.