Evidence for the presence of the Sanian 2 Glaciation (MIS 12) ice-sheet – a case study of palaeobasins from the Mazovian Interglacial (MIS 11c) and terrain relief in Wantopol site (E Poland)

Abstract

In the vicinity of Wantopol (Western Polesie, E Poland), present-day depressions in the landscape (Wantopol sites A, D and E) contain limnic and peat sediments with palynologic spectra and local macrofossil assemblages diagnostic of the Mazovian (Holsteinian, MIS 11c) Interglacial. The palaeobasins were carved in glacial tills of the Sanian 2 (Elsterian, MIS 12) Glaciation covering the entire area. The sediments covering the interglacial deposits are mostly of dilluvial origin and correlated with the Vistulian (Weichselian) Glaciation. The palaeobasins were formed as a result of aerial deglaciation of the Sanian 2 (Elsterian, MIS 12) ice-sheet by melting of dead-ice blocks in a depression (Wantopol A) and a shallow post-glacial trough (Wantopol D and E). Moreover, further evidence for this type of deglaciation of the Sanian 2 ice-sheet is a kame located in the vicinity of the studied sites, composed mainly of sandy sediments topped with a gravel layer. Sediments building the kame were deposited in a crevasse within the melting ice-sheet. The presence of glacial tills and the geological context of the interglacial sediments overlying them are proof of the presence of the Sanian 2 ice-sheet and for this being the last one that occurred in the study area.