Multidisciplinary study of Middle-Upper Pleistocene deposits in a core from the Piana Pontina (central Italy)

The results of a multidisciplinary study on two sedimentary cores drilled in the Piana Pontina (Central Italy) are reported and discussed. On the basis of lithostratigraphic, sedimentological, faunistic (molluscs, ostracodes), floristic (pollen), aminostratigraphic, radiometric and geochemical analyses, the geological evolution of the study area from the Middle Pleistocene to the beginning of the Last Glacial has been reconstructed. The area has been subjected to two main marine ingressions, corresponding respectively to oxygen isotope Stages 9 or 7 and 5, separated by an important continental phase referred to Stage 6. The beginning of the Last Glacial is represented by freshwater sediments indicating cool and dry climatic conditions. As the Tyrrhenian deposits of the last marine ingression (Substage 5e) occur at about 12 m below sea level in the study sequences while in the adjacent western coastal area the corresponding shorelines occur at 7.5-16 m above sea level, a post-Tyrrhenian subsidence with a mean rate of about 0.09-0.15 m/ka connected both with tectonic movements and the compaction of Pleistocene sediments can be inferred.