Luminescence dating of Weichselian interstadial sediments from the German Baltic Sea coast

Abstract

A cliff outcrop called Kluckow, in the Baltic Sea area, with a (glacio-) fluvial to (glacio-) lacustrine succession, provides a unique opportunity to resolve uncertainties in the timing and extent of several poorly constrained Weichselian ice advances. Based on a detailed lithofacies analysis, we selected four sampling horizons for luminescence dating to determine a depositional chronology. We measured both coarse-grain quartz and potassium-rich feldspar for age determination using optically stimulated luminescence (OSL) and post-IR infrared stimulated luminescence (pIRIR). Furthermore we addressed potential problems such as incomplete bleaching and quartz saturation effects. The resulting luminescence-chronology, supported by one radiocarbon age, illustrates a depositional time interval of the investigated sequence between ∼62 and ∼22 ka. Within this sequence a mussel-bearing fluvial sand indicate interstadial climate conditions at approximately 46 ka. The upper part of the section is composed of a 4 m thick glaciolacustrine silty clay and an overlying glaciofluvial sand; the latter yielded an OSL age of ∼22 ka. Shortly after these sequences formed, the subsequent ice advance (indicated by the overlying till sheet) reached the study area. Based on our new chronology and lithofacies analysis, we conclude that the Scandinavian Ice Sheet did not reach the study area between ∼62 and ∼22 ka.