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

Lorenz Wüthrich, Marcel Bliedtner, Imke Kathrin Schäfer, Jana Zech, Fatemeh Shajari, Dorian Gaar, Frank Preusser, Gary Salazar, Sönke Szidat, Roland Zech
2017 Eiszeitalter und Gegenwart  
<p><strong>Abstract.</strong> We present the results of leaf wax analyses (long-chain <i>n</i>-alkanes) from the 6.8<span class="thinspace"></span>m deep loess sequence of Möhlin, Switzerland, spanning the last ∼ <span class="thinspace"></span>70<span class="thinspace"></span>kyr. Leaf waxes are well preserved and occur in sufficient amounts only down to 0.4<span class="thinspace"></span>m and below 1.8<span class="thinspace"></span>m depth, so no paleoenvironmental reconstructions can be done
more » ... or marine isotope stage (MIS) 2. <br><br> Compound-specific <i>δ</i><sup>2</sup>H<sub>wax</sub> 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 ∼ <span class="thinspace"></span>30<span class="thinspace"></span>‰ shift towards more negative values probably reflects more humid conditions before ∼ <span class="thinspace"></span>32<span class="thinspace"></span>ka. Radiocarbon dating of the <i>n</i>-alkanes corroborates the stratigraphic integrity of leaf waxes and their potential for dating loess–paleosol sequences (LPS) back to ∼ <span class="thinspace"></span>30<span class="thinspace"></span>ka.</p>
doi:10.5194/egqsj-66-91-2017 fatcat:fu6kxyla3nfidmkuqmdkjpfvva