EGU22-12498
https://doi.org/10.5194/egusphere-egu22-12498
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Upper Pleistocene dust dynamics reconstructed by isotope fingerprinting and the magnetic fabric of Loess-Palaeosol-Sequences 

Mathias Vinnepand1, Peter Fischer1, Carol-Ann Craig2, Ulrich Hambach3, Christian Zeeden4, Barry Thornton2, Thomas Tütken1, Olaf Jöris5, Charlotte Prud'homme6, Philipp Schulte7, Olivier Moine8, Kathryn Fitzsimmons9, Frank Lehmkuhl7, Wolfgang Schirmer10, and Andreas Vött1
Mathias Vinnepand et al.
  • 1Johannes Gutenberg-Universität Mainz, Germany
  • 2The James Hutton Institute, Aberdeen, Scotland/UK
  • 3BayCEER & Chair of Geomorphology, University of Bayreuth, Germany
  • 4Leibniz Institute for Applied Geophysics, Hannover, Germany
  • 5Römisch-Germanisches Zentralmuseum, Neuwied, Germany
  • 6University of Lausanne, Switzerland
  • 7RWTH Aachen, Germany
  • 8French National Centre for Scientific Research, Meudon, France
  • 9Eberhard Karls University Tübingen formerly Max-Planck-Institute for Chemistry, Mainz, Germany
  • 10Wolkenstein, Germany

Loess-Palaeosol-Sequences (LPS) are the most widespread aeolian sedimentary deposits providing climatic- and environmental records across continents. As dust sinks, they may archive information on dust source dynamics, if targeted source signals survived processes operating during production, transport, and syn- and post-depositional alteration of particles and sediments. Yet, our knowledge about such dynamics through palaeoenvironmental changes during the Upper Pleistocene remains vague. This limits our understanding of thresholds that may have (de-) activated dust sources causing major environmental changes in prevalent areas. We thus combine results of isotope- (87/86Sr, 143/144Nd) and major element (Si/Al) provenance proxies that react differently to pre-, syn- and post depositional alteration processes, with granulometry (U-ratio) and the anisotropy of magnetic susceptibility (AMS). Granulometry is recognised as an indicator for wind strengths and the primary magnetic fabric of loess deposits has been successfully used to reconstruct surface near wind directions. We apply our approach on the RP1 profile of the Schwalbenberg LPS that covers the late OIS 3 and the OIS 2 in centennial-scale resolution. The site is embedded in the Middle Rhine Valley (Germany) dividing the Rhenish Massif in its western and eastern part. Consequently, the Schwalbenberg seems appropriate to trace provenance shifts as it is linked to a distal dust source via the Rhine and as it is surrounded by potential local dust sources of the Rhenish Massif. Our results indicate shifts in source areas NNE-SSW off the site, contemporary with increasing frost dynamics and aridification. Both factors seem to enhance dust inputs from the Rhine system up to a threshold where the Rhenish Massif gets activated as a dominant source. Geochemical fingerprinting and AMS at the Schwalbenberg RP1 LPS reveal insights into dust source dynamics that allow for estimating their emission potential during Upper Pleistocene palaeoenvironmental changes.  

How to cite: Vinnepand, M., Fischer, P., Craig, C.-A., Hambach, U., Zeeden, C., Thornton, B., Tütken, T., Jöris, O., Prud'homme, C., Schulte, P., Moine, O., Fitzsimmons, K., Lehmkuhl, F., Schirmer, W., and Vött, A.: Upper Pleistocene dust dynamics reconstructed by isotope fingerprinting and the magnetic fabric of Loess-Palaeosol-Sequences , EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12498, https://doi.org/10.5194/egusphere-egu22-12498, 2022.