To comparison of bulk chemical composition of Lower Permian clay rocks (Uruzano-Sylvinskaya and Belsk depression)

Analysis of the lithogeochemical characteristics of the Lower Permian clay rocks from Belsk and Uruzano-Sylvinskaya depressions of the PreUralian foredeep indicates that there are no principal differences between them, which may indicate the presence of a single source of deposited material. Bulk chemical composition of the Lower Permian clay rocks is comparable to PAAS content of SiO 2, TiO 2, Al 2O 3, FeOtot, K2O and P2O5. A difference of composition is observed only in MgO, CaO and Na2O. Content of Cr, Co, Ni, and Zn in most mudstone from Belsk depression is higher than in Uruzano-Sylvinskaya depression. Simultaneously, mudstone from the basin of Ufa River has slightly higher concentrations of Sc, Sr, Y, Mo and REE. Distribution of REE in mudstone of the two basins is comparable. Their general depletion by light lanthanides in comparison with PAAS, and a low positive Eu К сопоставлению валового химического состава глинистых пород нижней перми... 32 anomaly suggest the presence a substantial portion of the products of erosion of the basic magmatic complexes in the clay rocks.