Geochemistry and mineralogy of the Poznań Formation (Polish Lowlands)

This book presents the geochemical characteristics of Mio-Pliocene clays (known as Poznań clays in polish literature) from selected deposits of the Polish Lowland on the background of their mineralogical composition. The aim of the study was the evaluation of weathering on the composition of the clays. The chemical composition was analysed with INAA, ICP-MS and XRF methods. All the clay samples studied showed large chemical homogeneity expressed in the low variability of CIA and CIW indexes, on the basis of which it was found a preponderant share of the chemical weathering during the sediment formation. The geochemistry and mineralogy of the Mio-Pliocene clays from open pits were compared which those of the clays from two boreholes. The CIA and CIW indexes were similar suggesting that the main chemical features of the sediments had been formed already at the time of their deposition. The variability of the concentration of trace elements in the fine fractions (