Substance composition of Neoproterozoic high-K terrigenous sediments of Karagas group (Biryusa Prisayanie) and the possible sources of clastic material – Paleoproterozoic granites (Sayan complex) and more ancient metamorphic formations Sublukskaya group of the Biryusinskaya blocks are studied. Constraints on possibility of the proposed complexes as sources of clastic material in the genesis of Karagas group deposits is established. Particular attention is paid to mineralogical and petrographic features of the rocks studied, as well as probable geological formations, whose rocks could serve as a protolith for the terrigenous deposits of the Karagas series. As a result of the conducted studies, a very limited possibility of their participation as sources of detrital material in the formation of the sediments under consideration has been established. When studying the material characteristics it was revealed that the rocks of the Karagas series have a volcaniclastic nature associated with the activity of alkaline magmatism. Available at the disposal of the authors of U–Pb dating of detrital zircons of the Karagas series are characterized by age values in the interval 630–640 Ma. Such age limits are also observed in the rocks of the Beloziminsky carbonatite massif, also located within the Biryusa Pripyat. Thus, the totality of the results obtained clearly demonstrates the intensive manifestation of alkaline magmatism and volcanism in this area.

Federyagina Ekaterina Nikolaevna, Lecture, Geology Faculty, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, tel.: 8(3952)24-39-89, e-mail: katerinka19.85@mail.ru 

Andreeva Yulia Sergeevna, Lecture, Geology Faculty, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, Vinogradov Institute of Geochemistry SB RAS, 1, Favorskii st., Irkutsk, 664033, Russian Federation, tel.: 8(3952)24-39-89, e-mail: afanasevaus@mail.ru 

Ivanov Aleksandr Vladimirovich, Undergraduate, Geology Faculty, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail:ivanov-tunguska@mail.ru

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