Late Quaternary climate and environmental reconstruction based on leaf wax analyses in the loess sequence of Möhlin, Switzerland

We present the results of leaf wax analyses (long-chain n-alkanes) from the 6.8 m deep loess sequence of Möhlin, Switzerland, spanning the last  ∼  70 kyr. Leaf waxes are well preserved and occur in sufficient amounts only down to 0.4 m and below 1.8 m depth, so no paleoenvironmental reconstructions can be done for marine isotope stage (MIS) 2. Compound-specific δ2Hwax analyses yielded similar values for late MIS 3 compared to the uppermost samples, indicating that various effects (e.g., more negative values due to lower temperatures, more positive values due to an enriched moisture source) cancel each other out. A pronounced  ∼  30 ‰ shift towards more negative values probably reflects more humid conditions before  ∼  32 ka. Radiocarbon dating of the n-alkanes corroborates the stratigraphic integrity of leaf waxes and their potential for dating loess–paleosol sequences (LPS) back to  ∼  30 ka

10Be depth profiles in glacial sediments on the Swiss Plateau: deposition age, denudation and (pseudo-) inheritance.

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10Be surface exposure dating of the last deglaciation in the Aare Valley, Switzerland

The combined Rhone and Aare Glaciers presumably reached their last glacial maximum (LGM) extent on the Swiss Plateau prior to 24 ka. Two well-preserved, less extensive moraine stades, the Gurten and Bern Stade, document the last deglaciation of the Aare Valley, yet age constraints are very scarce. In order to establish a more robust chronology for the glacial/deglacial history of the Aare Valley, we applied 10Be surface exposure dating on eleven boulders from the Gurten and Bern Stade. Several exposure ages are of Holocene age and likely document post-depositional processes, including boulder toppling and quarrying. The remaining exposure ages, however yield oldest ages of 20.7 ± 2.2 ka for the Gurten Stade and 19.0 ± 2.0 ka for the Bern Stade. Our results are in good agreement with published chronologies from other sites in the Alps.Fil: Wüthrich, Lorenz. University of Bern; SuizaFil: Garcia Morabito, Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Diversidad Cultural y Procesos de Cambio. Universidad Nacional de Río Negro. Instituto de Investigaciones en Diversidad Cultural y Procesos de Cambio; Argentina. University of Bern; SuizaFil: Zech, Jana. University of Bern; SuizaFil: Trauerstein, Mareike. University of Bern; SuizaFil: Veit, Heinz. University of Bern; SuizaFil: Gnägi, Christian. University of Bern; SuizaFil: Merchel, Silke. Helmholtz-zentrum, Dresden-rossendorf, Deutschland; AlemaniaFil: Scharf, Andreas. Helmholtz-Zentrum; AlemaniaFil: Rugel, Georg. Helmholtz-Zentrum; AlemaniaFil: Christl, Marcus. Eidgenössische Technische Hochschule Zürich; SuizaFil: Zech, Roland. University of Bern; Suiz