Late Quaternary Iceberg rafting along the Antarctic Peninsula continental rise and in the Weddell and Scotia Seas

  • Cofaigh C
  • Dowdeswell J
  • Pudsey C
  • 43

    Readers

    Mendeley users who have this article in their library.
  • 39

    Citations

    Citations of this article.

Abstract

Sediment cores from the continental rise west of the Antarctic Peninsula and the northern Weddell and Scotia Seas were investigated for their ice-rafted debris (IRD) content by lithofacies logging and counting of particles >0.2 cm from core x-radiographs. The objective of the study was to determine if there are iceberg-rafted units similar to the Heinrich layers of the North Atlantic that might record periodic, widespread catastrophic collapse of basins within the Antarctic Ice Sheet during the Quaternary. Cores from the Antarctic Peninsula margin contain prominent IRD-rich units, with maximum IRD concentrations in oxygen isotope stages 1, 5, and 7. However, the greater concentration of IRD in interglacial stages is the result of low sedimentation rates and current winnowing, rather than regional-scale episodes of increased iceberg rafting. This is also supported by markedly lower mass accumulation rates (MAR) during interglacial periods versus glacial periods. Furthermore, thinner IRD layers within isotope stages 2-4 and 6 cannot be correlated between individual cores along the margin. This implies that the ice sheet over the Antarctic Peninsula did not undergo widespread catastrophic collapse along its western margin during the late Quaternary (isotope stages 1-7). Sediment cores from the Weddell and Scotia Seas are characterized by low IRD concentrations throughout, and the IRD signal generally appears to be of limited regional significance with few strong peaks that can be correlated between cores. Tentatively, this argues against pervasive, rapid ice-sheet collapse around the Weddell embayment over the last few glacial cycles. © 2001 University of Washington.

Author-supplied keywords

  • Antarctic Ice Sheet
  • Antarctic Peninsula
  • Ice-rafted debris
  • Quaternary
  • Weddell and Scotia Seas

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Colm Ó Cofaigh

  • Julian A. Dowdeswell

  • Carol J. Pudsey

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free