The Late Glacial pedogenesis interrupted by aeolian activity in Central Poland - records from the Lake Gosciaz catchment

An interdisciplinary study was undertaken to reconstruct the Late Glacial fluvioglacial and aeolian sediment transformations with a particular focus on soil-forming processes. The studies included complex pedological research (physical and chemical properties), X-ray diffraction (XRD) analysis of clay minerals and Optically Stimulated Luminescence (OSL) dating on soil/deposit sequences developed within the aeolian landscape of inland dunes in the Lake Gosciaz catchment (Central Poland). Late Glacial buried Bwb soil horizons are known as Finow soils'. This paleosol was identified in the central part of inland dunes (in vertical perspective), developed from aeolian material deposited on fluvioglacial sediments. The average content of silt and clay in this paleosols ranged from 7.3% to 41.1% and from 6.7% to 12.6%, respectively. In other soil horizons within profiles, the average content of these granulometric fractions was about 3% and 1.5%, respectively. The dominance of dioctahedral vermiculite and the higher content of free iron oxides (especially oxalate form) and aluminium within Bwb horizons indicates their pedogenic origin. The OSL dates suggested that Finow soil fossilization began along with the development of aeolian processes in the late-glacial cold periods (the Older Dryas and the Younger Dryas), while Finow soil development took place in the warmer periods of the Late Glacial (Bolling-Allerod). These results were consistent with data from Germany, other stands in northern Poland and the Tomsk Priobye Region (SE western Siberia).