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Presented are the results of research into the fluvio-aeolian sedimentary succession at the site of Postolin in the Żmigród Basin, southwest Poland. Based on lithofacies analysis, textural analysis, Thermoluminescence and Infrared-Optical Stimulated Luminescence dating and GIS analysis, three lithofacies units were recognised and their stratigraphic succession identified: 1) the lower unit was deposited during the Pleni-Weichselian within a sand-bed braided river functioning under permafrost conditions within the central part of the alluvial fan; 2) the middle unit is the result of aeolian deposition and fluvial redeposition on the surface of the fan during long-term permafrost and progressive decrease of humidity of the climate at the turn of the Pleni- to the Late Weichselian; 3) the upper unit accumulated following the development of longitudinal dunes at the turn of the Late Weichselian to the Holocene; the development of dunes was interrupted twice by the form being stabilised by vegetation and soil development.

During the Pomeranian phase of the Weichselian glaciation (~17-16 ka), the Toruń-Eberswalde ice-marginal valley (NW Poland and easternmost Germany) drained water from the Pomeranian ice sheet, while intensive aeolian processes took place across Europe in the foreland of the Scandinavian ice sheet (‘European Sand Belt’). The micromorphology of the quartz grains in the Toruń-Eberswalde ice-marginal valley shows no traces of these aeolian processes, or only vague signs of aeolian abrasion. This is unique among the aeolian sediments in other Pleistocene ice-marginal valleys in this part of Europe. The study of the surfaces of the quartz grains shows that the supply of grains by streams from the south was minimal, which must be ascribed to the climate deterioration during the Last Glacial Maximum, which resulted in a decrease of the discharge of these extraglacial rivers to the ice-marginal valley.