IR-OSL studies of till and inter-till deposits from the Lithuanian Maritime Region

Abstract

Glacial till and inter-till deposits exposed in the Lithuanian coastal region are evidence for multiple glacial advances during the Pleistocene. Stratigraphically, tills are the most important, prominent and well preserved deposits. However, despite the importance of these deposits, there is limited chronological control and it is widely debated whether they belong to one or another Pleistocene glaciation. The aim of the present study was to find features of the glacigenic tills, which allow us to temporally constrain these deposits, which are usually deemed to be undateable by luminescence methods. To achieve the goal, 15 samples from five different till beds and 12 samples from underlying sandy inter-till deposits from the same area were taken for analysis by feldspar-based IR-OSL technique. This paper presents the results, which suggest that the studied deposits, including glacial tills, are mostly of late Pleistocene age (MIS 5 and 4). We discuss analytical data obtained for these materials and implications for stratigraphic subdivision of the till-bearing deposits in the Lithuanian Maritime Region.