The maximum extent of the Odranian Glaciation (Saalian, MIS 6) in the South Podlasie Lowland (SE Poland) in the light of sites with lacustrine deposits of the Mazovian Interglacial

Abstract

Based on the analysis of the geological context and palynological studies performed on lake and bog sediments in the Southern Podlasie Lowland, a new concept of the maximum extent of the Odranian Glaciation (Saalian, MIS 6) is presented for the study area. It is depicted by the Siedlce-Łosice-Kornica zone of end moraines, which so far was considered as stadial-rank or as the Wartanian ice sheet limit. To the south of this zone, near Biała Podlaska and in the Łuków Plain, there occur numerous sites with fossil deposits of the Mazovian Interglacial (MIS 11c). Sites with new documentation, i.e., Wólka Domaszewska, Kolonia Bystrzycka, Przytulin, Hermanów, and Skrzynka are located about 30 km to the south and 6 km to the west of the Biała Podlaska area. Palynological analysis unequivocally indicates the presence of a vegetation succession characteristic of the Mazovian Interglacial. In all sites, deposits of the Mazovian Interglacial are covered by lacustrine sediments of the Liviecian Glaciation (Fuhne, MIS 11b-MIS 10) or mineral sediments of the Vistulian Glaciation (Weichselian, MIS 2) and the Holocene. The sediments infill paleolakes carved in glacial tills of the Sanian 2 Glaciation (MIS 12). The lake sediments of the Mazovian Interglacial and the overlying biogenic and mineral deposits occur in the analysed sites directly below the surface. They are never covered by glacial deposits, which suggests that the Odranian ice sheet did not cover the study area. The location of the lake and bog sites with their geological analysis allow for the precise depiction of the eastern limit of the Odranian ice sheet lobe, which in the study area correlates with the limit suggested in the late 19th century. The Odranian ice sheet did not cover Southern Podlasie.