부산대학교 도서관

Short-term climate oscillations known form the Last Glacial Termination (LGT) have been firstly recognized in the Greenland ice cores as well as in the deep-marine and lacustrine profiles. Such climate changes have also been marked in terrestrial depositional environments, particularly in the fluvio-aeolian succession of the European Sand Belt (ESB). This is due to the high sensitivity of this depositional environment to changes in environmental conditions. However, unlike, for example, annually laminated lake sediments, dating the chronology of these changes encounters great difficulty. These are due to the peculiarities of sedimentary processes (especially aeolian), punctuated by periods of stabilization and development of soil covers. Comparison of previously accepted stratigraphic models of fluvio-aeolian succession with recent research results indicated the need for a new approach to the question of the chronology and rank of these processes. Therefore, a large-scale research project in the central part of the ESB was launched in 2019 to determine the chronology of sedimentary and soil processes and how they relate to global climate change during the LGT. To this end, detailed sedimentological, paleobiological, soil and geochemical studies have been carried out in more than 50 dune profiles. More than 300 luminescence and about 70 14C results have been madefor the studied sedimentary successions. The results obtained so far indicate that the response of depositional environments and their evolution creates a more complicated pattern than previously assumed. First of all, the beginning of intensive aeolian deposition as early as the turn of the oldest Dryas and Bølling and 2 distinct phases of dune formation during the warming of the Allerød interstadial are marked. More variability in aeolian accumulation and soil-forming processes is recorded in the Younger Dryas. All this is compounded by several local factors (permafrost disappearance, river incision, bedrock lithology) that modified the response of the fluvio-aeolian environment to climatic oscillations. The use of sufficiently dense sampling for OSL and radiocarbon dating made it possible to develop a new stratigraphic model, despite date inversions appearing in some profiles. This confirms the advantage of using both dating methods in the same profiles to cross-check them and eliminate reliably questionable results from further stratigraphic considerations. [ABSTRACT FROM AUTHOR]