Résultats préliminaires sur la sédimentation pélagique de l'Atlantique tropical au Crétacé et au Tertiaire (plateau de Demerara, Leg ODP 207)

Translated title of the contribution: Preliminary results on Cretaceous-Tertiary tropical Atlantic pelagic sedimentation (Demerara Rise, ODP Leg 207)

Taniel Danelian*, Laurence Le Callonnec, Jochen Erbacher, David C. Mosher, Mitchell J. Malone, Debora Berti, Karen L. Bice, Helen Bostock, Hans Jürgen Brumsack, Astrid Forster, Felix Heidersdorf, Jorijntje Henderiks, Thomas J. Janecek, Christopher Junium, Ken MacLeod, Philip A. Meyers, Jörg H. Mutterlose, Hiroshi Nishi, Richard D. Norris, James G. OggMatthew A. O'Regan, Brice Rea, Philip Sexton, Helen Sturt-Fredricks, Yusuke Suganuma, Jürgen W. Thurow, Paul A. Wilson, Sherwood W. Wise, Christine Glatz

*Corresponding author for this work

Research output: Contribution to journalArticle

7 Citations (Scopus)


Five sites located on a bathymetric transect of the distal Demerara Rise were studied by ODP Leg 207. Albian sediments of essentially terrigenous nature (clay, siltstone, sandstone) are the oldest drilled stratigraphic levels and form apparently the top of the synrift sequence. They are overlain by Cenomanian to Santonian finely laminated black shales, rich in organic matter of marine origin, which accumulated on a thermally subsiding ramp. Early Campanian hiatuses are thought to be the result of final disjunction of Demerara Rise (South America) from Africa and the onset of deep water communication between the two Atlantic basins (south and central). The overlying Uppermost Cretaceous-Oligocene chalk includes rich and diversified calcareous plankton assemblages, as well as two radiolarian-rich intervals (Late Campanian and Middle Eocene). A complex erosional surface developed during the Late Oligocene-Early Miocene. Sedimentation was impeded since then on the intermediate and deep sites of Demerara Rise, possibly due to the action of deep submarine currents.

Original languageFrench
Pages (from-to)609-616
Number of pages8
JournalComptes Rendus. Ge´oscience
Issue number6
Publication statusPublished - 1 Apr 2005



  • Black shales
  • Cretaceous
  • Demerara
  • Tertiary
  • Tropical Atlantic

ASJC Scopus subject areas

  • Earth and Planetary Sciences(all)
  • Global and Planetary Change

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