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New luminescence-based geochronology framing the last two glacial cycles at the southern limit of European Pleistocene loess in Stalać (Serbia)

Bösken J., Klasen N., Zeeden Ch., Obreht I., Marković S. B., Hambach U., Lehmkuhl F.

Geochronometria

2017

Vol. 44, no. 1

150--161

A new geochronology was established for the Stalać loess-paleosol sequence (LPS) in Serbia. The section is located in the interior of the Central Balkan region, south of the typical loess distribution, in a zone of paleoclimatic shifts between continental and Mediterranean climate regimes. The sampled sequence contains four well-developed paleosol and loess layers, a crypto tephra and one visible tephra layer. Optically stimulated luminescence measurements showed a strong dependency of preheat temperature on equivalent dose for one fine-grained quartz sample, which makes it unsuitable for dating. A firm chronology framing the last two glacial cycles was established using finegrained polyminerals and the post-infrared infrared stimulated luminescence (pIR50IR290) protocol instead. The characteristics of dated paleosols indicate similar climatic conditions during the last interstadial and interglacial phases, which were different from the penultimate interglacial period. The tephra within the L2 loess, probably related to tephra layers also found in other sections in Southeastern Europe, was sandwich-dated. The results indicate an age between 118 ka and 141 ka. Furthermore, a weak pedogenic layer dated to between 126 ka and 148 ka gives a first numerical age to this soil formation in Southeastern Europe.

Luminescence dating of loess deposits from the Remagen-Schwalbenberg site, Western Germany

Klasen N., Fischer P., Lehmkuhl F., Hilgers A.

Geochronometria

2015

Vol. 42, no.1

67--77

This study describes the luminescence characteristics of quartz of Upper Pleistocene loess of the Middle Rhine area. The loess/palaeosol sequence of the Schwalbenberg near Remagen comprises a multitude of interstadial soils and soil sediments that have been dedicated to the Marine Isotope Stage 3 (MIS 3). These weak calcaric cambisols and their derivates are underlain by loess and soil sediments of MIS 4 to MIS 5 and covered by loess sediments and intercalated gelic gleysols of MIS 2. We applied luminescence dating of quartz and feldspar of drill core samples and observed an age discrepancy within both data sets. The quartz ages were clearly younger than the feldspar ages, because of thermally unstable signal components of the quartz luminescence signal. Therefore, we regarded the quartz samples of the lower parts of the drill core as unsuitable for luminescence dating. This underestimation did not affect the quartz samples of the upper part of the drill core which was indicated by age control that was provided by the Eltville tephra layer. Geochemical analysis based on X-ray fluorescence showed that the sediments in the upper part and the lower part of the drill core have different geogenic finger prints most likely due to changing source areas of dust and sediment allocation. We assumed that these different facies types were the reason for the luminescence behavior of the quartz samples.