Mineralogical Composition and Provenances

Based on available data, the cyclic diagrams of the mineralogical composition of a light fraction within facies zones different stratigraphic intervals, i.e., in Break suite, Balakhani, Sabunchi, and Surakhani suites. As it is known, the paleo-Volga sediments are characterized by a very high content of quartz washing out from the Russian platform’s crystalline basement. The average quartz content is about 40-55%, up to 90% in some cases. The presence of the rest of the light fraction components – feldspars and rock waste - does not exceed 20%. As a distributive province, the Greater Caucasus is thought to play an important role, though not as the Russian platform, in developing many SCB structures. The clastic material has been supplied from the northern slope by mountain rivers to the paleo-Volga itself. It merged in the total balance of solid runoff from the southern slope to the basin itself. The distinctive feature is that the rock debris is widely present in light fracture (up to 60-80%) while the rest components are lacking.