干旱区生态环境知识资源中心

An optically stimulated luminescence technique with a high-resolution sampling strategy, as well as a set of multiple proxies such as grain size distribution, shape, surface and microstructures of quartz grains, along with mineral composition of light and heavy fractions was used to investigate the age and origin of fan-like forms at the southern margin of Mazovian Lowland, Poland. The predominance of aeolian factors was observed throughout all of the investigated sites. However, the sedimentary variability of the grains reflected the superposed influence of multiple cold environmental factors such as snow/ice interbedded layers, cryoturbation processes or a "fluvial" transformation. Luminescence ages provide the first detailed chronology of the southern margin of the Mazovian Lowland. Deposition began after ca. 42 ka and onwards, and resulted in the depositional alternation of dry and humid environmental interactions. Between ca. 31 and 25 ka, the pre-LGM aeolian transformation took place. Finally, during the Pomeranian Phase in Poland at similar to 14 ka, polar desert environmental conditions prevailed.