STRATYGRAFIA, PETROGRAFIA I PALEOGEOGRAFIA GLIN LODOWCOWYCH W REJONIE PÓŁNOCNO-ZACHODNIEGO WYBRZEŻA POLSKI

Abstract

TILL STRATIGRAPHY, PETROGRAPHY AND PALAEOGEOGRAPHY ALONG THE NORTHWESTERN COASTAL REGION OF POLANDAbstract. There are 10 till horizons of different ages in the northwestern coastal region of Poland, representing the “oldest” glaciation (2 horizons), Elsterian glaciation (3), Saalian glaciation (3) and the last glaciation (2). Some stratigraphic horizons contain tills of regionally variable petrographic composition, which usually represent tills from different lobes of the same ice sheet advance. Several till horizons have features similar to the tills defined in the southern part of the Szczecin region, others have a petrographic composition specific only to the northwestern coastal region of Poland. The last ones have been newly and formally defined, with an indication of stratotype sections, characteristic features and extents. In the northwestern coastal region of Poland, the till horizons occur sporadically and they do not form continuousbeds. Glacial lobes have been proved for the late Elsterian, late Saalian and for both Weichselian advances. Their occurrence (especially during the latest advances coming from the northeast or east) is due to their location in the southern Baltic basin, where the ice sheets differentiated into the lobes that continued their advances towards the west toNWGermany and Denmark, and those that deflected along the Odra rivervalley (Odra lobe) towards the SW and south to SE Germany and western Poland. Moreover, Eemian marine sediments, clay or sand with mollusc fauna have been found in the northwestern coastal region. They occur at a depth of 5.5–19.6m below the present-day sea level. They were deposited in a shallow bay extending about 10 km inland. The location of these sediments suggests a marine transgression into a pre-existing tunnel valley.