Obliquity forcing of Quaternary glaciation and environmental changes in NE Siberia

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • W. Zech - , Universität Bayreuth (Autor:in)
  • Roland Zech - , Brown University (Autor:in)
  • M. Zech - , Universität Bayreuth (Autor:in)
  • K. Leiber - , Universität Bayreuth (Autor:in)
  • M. Dippold - , Universität Bayreuth (Autor:in)
  • M. Frechen - , Leibniz-Institut für Angewandte Geophysik (Autor:in)
  • R. Bussert - , Technische Universität Berlin (Autor:in)
  • A. Andreev - , Universität zu Köln (Autor:in)

Abstract

Reconstructing Quaternary glacial and environmental changes in the vast, high-northern latitudes of Siberia is essential for a better understanding of global past climate variability and its potential solar forcings. Two sediment outcrops in the Dyanushka Valley in the southwestern foreland of the Verkhoyansk Mountains, northeast Siberia, were investigated using a multi-proxy approach (lithostratigraphy, geochemistry, palynology, and radiocarbon and IRSL dating). Three piedmont glaciations reached the outcrop sites. The glacial advances are dated to >140, ∼119-92 and ∼78-53 ka and thus, within dating uncertainties, correspond to obliquity minima during marine isotope stages (MIS) 6, 5d, and 4. This chronology corroborates and refines previous studies that have documented the successively more restricted glacial extents in Siberia during the course of the last glacial cycle. The observed glaciation pattern is out of phase with global ice volume estimates and probably indicates a strong aridisation trend. Additionally, the results show that the geochemical and mineralogical composition of the sediments contains information about provenance. Sediments originating from the Verkhoyansk Mountains are generally enriched in TiO2, MgO, P2O5, Fe2O3, Cr, illite, and chlorite, whereas sediments derived from the Lena River contain more expandable clay minerals, Ba, Sr. Alkane patterns as biomarker proxies turn out to be particularly valuable where poor preservation of pollen is an issue, and, generally speaking, vegetation reconstruction helps distinguishing between 'warm versus cold mode' sediments.

Details

OriginalspracheEnglisch
Seiten (von - bis)133-145
Seitenumfang13
FachzeitschriftQuaternary international
Jahrgang234
Ausgabenummer1-2
PublikationsstatusVeröffentlicht - 1 Apr. 2011
Peer-Review-StatusJa
Extern publiziertJa

Externe IDs

ORCID /0000-0002-9586-0390/work/170107112

Schlagworte

ASJC Scopus Sachgebiete

Bibliotheksschlagworte