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Palynology of the Last 680,000 Years of ODP Site 658 (off NW-Africa):fluctuations in paleowind systems

  • Lydie M. Dupont
Part of the NATO ASI Series book series (ASIC, volume 282)

Abstract

Sediments from ODP Site 658 at 21°N west of Cap Blanc show relatively high pollen concentrations and were deposited at high sedimentation rates. Detailed pollen analysis of the upper 100 m provide an unique record of vegetation and climate of NW Africa for the last 680 ka. With the help of pollen tracers, an estimate is made for the contribution of different transport systems to the total influx of the pollen taxa. High influx values for Poaceae and Cyperaceae that were transported by the African Easterly Jet (AEJ), indicate a northern position of the Sahel-Sahara boundary during periods with warm and humid conditions. During periods with cold and arid conditions the influx values for the NE trade wind transported pollen rise. On the average, pollen transport by the NE trade-winds increases during the last 680 ka; periods with warmest and most humid conditions occur only during the earlier part of the Brunhes Chron.

Keywords

Transport Capacity Pollen Production Arid Condition Pollen Taxon High Influx 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • Lydie M. Dupont
    • 1
  1. 1.Institute for Palynology and Quaternary SciencesUniversity of GöttingenGöttingenGermany

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