The first of two publications is devoted to the lithogeochemical features study of the pilot collection of the Upper Precambrian sandstones and siltstones samples, selected from four boreholes: Bogushevskaya 1, Bykhovskaya, Lepel 1 and Korminskaya (Belarus). This article analyzes the general features of their bulk chemical composition and shows the possibilities and limitations for further reconstructions. It has been established that the Riphean and the Vendian rocks included in the pilot collection, visually identified as sandstones, are actually quartz, feldspathic-quartz and arkose varieties with different cement types. The Vendian “siltstones” in their geochemical characteristics correspond to coarse- and fine-grained siltstones and, to a greater extent, mudstones with a predominance of illite, as well as various admixtures of berthierine, kaolinite and smectite. Considering the trace elements enrichment factors of these rocks a number of dissimilarities were identified, caused both by the source rocks composition and sedimentary environments changes. The data point position of the studied samples on the Zr/Sc–Th/Sc diagram suggests that the composition of all the Riphean and the Vendian rocks is dominated by first sedimentation cycle material. This suggests that the lithogeochemical characteristics of the rocks of the pilot collection quite correctly reflect similar features of the source rock complexes and can be used to reconstruct the paleogeodynamic and paleoclimatic factors that controlled the accumulation of the Riphean and the Vendian sedimentary sequences of Belarus.
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