Vendian Deposits of the Kolchim Uplift: Composition and Paleoclimate

The article presents the results of study of the mineral composition, structural, and textural features of the Vendian deposits from the Kolchim uplift, as well as the material composition of their pelitic fraction. Petrographic and X-ray phase and X-ray fluorescence analyses were used to study the rock samples. Based on the results of studies, the composition of the Vendian deposits from the Kolchim uplift was clarified and supplemented. For the first time, an attempt has been made at paleoclimatic reconstruction, which is based on the composition of clay material whith the main role assigned to illite. This allows concluding that the climate of the epoch is close to the nival type with a pre-dominance of physical weathering over chemical. Rock studies also confirm that the Vendian deposits consist of the erosion products from the underlying sediments of the Upper Riphean formations, as well as granitoids, and gneisses, the source of which are uplifts of the Timan with outcrops of the crystalline basement of the Russian Plate.