Palynomorph assemblages from the Upper Ordovician in northern and central

Palynological studies have been done to compare the Upper Ordovician strata in various geological units of northern and central Poland (epi-Caledonian Platform, East European Platform, Małopolska Block and Holy Cross Mountains–Łysogóry Fold Zone and Kielce Fold Zone). Two distinct palynological assemblages have been distinguished in the studied material: the Caradoc assemblage I and the Ashgill assemblage II (with two sub-assemblages IIa and IIb), thus demonstrating usefulness of the Upper Ordovician palynomorphs for biostrati- graphy. Thermal maturity of organic matter was studied using the TAI method. The palynological analysis, palynostratigraphy, and estimates of thermal maturity were done with the aim at palynological characterization of three ancient units: the Avalonia, Baltica and the Małopolska Block, all now participating in structures of the present-day geological units of northern and central Poland.