Ter tiary depos its in the Mid dle Vistula River val ley have been paly no logi cal ly stud ied. Sed i ments were inves ti gated dur - ing research for sev eral sheets (Dęblin, Kozienice, and Puławy) of the Detailed Geo log i cal Map of Poland in 1: 50,000 scale —. Seven palynological assem blages were rec og nized, con tain ing Upper Paleocene, Mid dle and Upper Eocene, Lower Oligocene, and Mid dle Mio cene palymomorphs. In the Paleogene marine depos its, a rich dinocysts assem blages becomes palynological marker, sporomorphs are less numer ous. In the Neo gene, sporomorphs are abun dant. Phytoplankton assem blage from the Paleocene depos its show pre dom i - na tion of marine coastal facies. Palynomorphs from Eocene sed i ments were depos ited far ther from the shore. The lower Oligocene assemblage was characteristic for brackish deposits with substantial admixture of sporoporphs and phytoclasts of continental origin . Middle Miocene sporomorphs characterize two types of vegetation assemblages. Lower parts of the Middle Miocene (VI Tricolporopollenites megaexactus zone) contain pollen grains from shrubby peatbogs and mixed mesophilous forest, indicating warm and dry climate. Upper part of the Middle Miocene (IX Tricolporopollenites pseudocingulum zone), dominating plant communities were swamp and riparian forest, thus indicating warm and wet climate.