Harsh periglacial climate at MIS 3/MIS 2 transition reflected in Central European Loess-Paleosol Sequences

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The Brandenburg / Leszno Phase of the last (Weichselian) glaciation represent the regional Last Glacial Maximum (LGM) in northeastern Germany and western Poland. Since recent OSL dating and geomor-phological results suggest a possibility of late MIS 3 age (30 to max. 34 ka) it appears that this regional LGM may predate the global LGM by up to 10 ka. Following the world-wide LGM review of HUGHES ET AL. (2013) more caution is advisable when correlating maximal regional extend of ice shields with proxies for global ice volume (MIS). In case of a late MIS 3 regional LGM an adjoining belt with harsh periglacial conditions is to be expected, for which first evidence was already found: An up to 6 m thick loess of typically pleniglacial habitus with OSL ages between ca. 29 and 35 ka was recently detected in the famous Nussloch section (Germany), and a ca. 2 m thick loess bed dated between ca. 28 and 33 ka with a grandiose network of ice vein casts has recently been published from Havringcourt, Pas-de-Calais (France) (ANTOINE ET AL: 2014). In several recent publications chronological equivalents of this loess but of minor thickness were dated ca. 30 ka in several other Central European loess sections. The project aims at proving meaningful additional evidence in loess of Silesia (Poland) and the Harz foreland (Germany).I hypothesize that a belt with harsh periglacial conditions several thousand years prior to the global LGM is reflected in parts of the Central European loess belt between the Scandinavian and the Alpine Glaciations, in particular in those areas exhibiting high loess sedimentation rates and situated relatively close to the regional maximum of the last Scandinavian glaciation. The proposed pilot project aims at supporting the hypothesis by OSL and IRSL dating from well-stratified key sections in Silesia (Poland), Saxony-Anhalt, as well as from further samples from the Nussloch site. Cooperation with SFB (CRC) 806 (Prof. F. Lehmkuhl) is agreed. In case of successful results obtained from this pilot project regional extension of this research to farther eastern Central European loess sections is envisaged for a following project.