Sand sources and migration of the dune fields in the central European Sand Belt - A pattern analysis approach

Long-standing studies of the fixed late-glacial dune fields of the European Sand Belt (ESB) indicate that its development was driven by the degradation of permafrost and the widespread incision of rivers. Ice-marginal valleys, smaller valleys and limnic sediments are considered to be the main sand sources for dune fields within the ESB. However, the provenance of particular dune fields has not been independently assessed. Hence, discussion on the dynamics of the ESB dune fields has been limited to general statements about the distance and duration of aeolian transport. This problem was addressed through the geomorphological (pattern) analysis of 40 dune fields located within the central ESB. Using the calculated construction times and assumed migration rates, we identified the distances covered by the dune fields and their potential sand sources. The study confirmed that fluvial and fluvioglacial sediments were the main sand sources for the ESB dune fields. Most dune fields were found to have migrated over distances of 5-15 km during their development, confirming the short and local aeolian transport. At the same time, long-distance migration of dunes in areas located far from the Fennoscandinavian Ice Sheet was not ruled out. Results indicate dune migration rates as low as 0.5-3.5 m/yr. comparable to contemporary dune fields in cold regions. The methods used have the potential for use in studies in dune fields of other climatic zones, although the results need further verification based on geochemical studies.