Depositional conditions on an alluvial fan at the turn of the Weichselian to the Holocene – a case study in the Żmigród Basin, southwest Poland

• Main Authors: Zieliński, Paweł, Sokołowski, Robert J., Fedorowicz, Stanisław, Woronko, Barbara, Hołub, Beata, Jankowski, Michał, Kuc, Michał, Tracz, Michał
• Format: Article in Journal/Newspaper
• Language: English
• Published: Adam Mickiewicz University Poznan 2016
• Subjects: climate change; periglacial environment; fluvial processes; aeolian processes; luminescence dating; permafrost
• Online Access: http://pressto.amu.edu.pl/index.php/logos/article/view/logos-2016-0012

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.