Sub- and supra-moraine loesses in the Vistula catchment (Poland) with regard to the age and extent of the Scandinavian ice-sheets

Abstract

The study focuses on the geochronology and correlation between loesses and glacial tills in the Vistula catchment in Poland, in an area covered by all Scandinavian ice-sheets and characterized by thick loess successions. The basis for this correlation was a litostratigraphic analysis of selected loess sites in the uplands, which are well-documented in the literature, and the occurrences of loess and loess-like deposits under the cover of glacial deposits in the lowland part of the Vistula catchment, characterized by a much sparser documentation. The nomenclature of loess horizons follows Maruszczak (2001) and Kukla (1987), but sometimes is significantlychanged, according to modern Quaternary stratigraphical schemes. According to the analysis, accumulation of almost all loess horizons distinguished so far has been documented in the Pleistocene succession of the Vistula catchment: the oldest – lower (LNd), middle (LNs), and upper (LNg); older: lower (LSd), middle (LSs), and upper (LSg); and younger: lowest (LMn), lower (LMd), middle (LMs), and upper (LMg). In most cases loess accumulation took place in steppe-tundra conditions preceding the maximum ice-sheet development during the succeeding Scandinavian glaciations. For selected sites, the loess occurrence is presented in superpositionto glacial tills and interglacial deposits. The distinguished loesses and glacial tills are tied to the stratigraphic schemes of the Pleistocene in Poland (Marks et al. 2016, 2019) and correlated with Ukrainian loess horizons (Łanczont et al. 2019).