The response of calcareous nannofossil assemblages to the Paleocene Eocene Thermal Maximum at the Walvis Ridge in the South Atlantic

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doi: 10.1016/j.marmicro.2008.12.005
Author(s): Raffi, Isabella; Backman, Jan; Zachos, James C.; Sluijs, Appy
Author Affiliation(s): Primary:
Universita degli Studi Gabriele d'Annunzio di Chieti-Pescara, Dipartimento di Geotecnologie per l'Ambiente e il Territorio, Chieti Scalo, Italy
Stockholm University, Sweden
University of California Santa Cruz, United States
Utrecht University, Netherlands
Volume Title: Marine Micropaleontology
Source: Marine Micropaleontology, 70(3-4), p.201-212. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0377-8398 CODEN: MAMIDH
Note: In English. Based on Publisher-supplied data; includes 2 appendices; illus.
Summary: Compositions and abundances of calcareous nannofossil taxa have been determined in a ca 170 kyrs long time interval across the Paleocene/Eocene boundary at 1-cm to 10-cm resolution from two ODP Sites (1262, 1263) drilled along the flank of the Walvis Ridge in the South Atlantic. The results are compared to published data from ODP Site 690 in the Weddell Sea. The assemblages underwent rapid evolution over a 74 kyrs period, indicating stressed, unstable and/or extreme photic zone environments during the PETM hyperthermal. This rapid evolution, which created 5 distinct stratigraphic horizons, is consistent with the restricted brief occurrences of malformed and/or weakly calcified morphotypes. The production of these aberrant morphotypes is possibly caused by major global scale changes in carbon cycling in the ocean-atmosphere system, affecting also photic zone environments. No marked paleoecologically induced changes are observed in abundances of the genera Discoaster, Fasciculithus and Sphenolithus at the Walvis Ridge sites. Surprisingly, there is no significant correlation in abundance between these three genera, presumed to have had a similar paleoecological preference for warm and oligotrophic conditions. Abstract Copyright (2009) Elsevier, B.V.
Year of Publication: 2009
Research Program: ODP Ocean Drilling Program
Key Words: 02 Geochemistry; 12 Stratigraphy, Historical Geology and Paleoecology; Algae; Assemblages; Atlantic Ocean; Biologic evolution; C-13/C-12; Carbon; Cenozoic; Eocene; Isotope ratios; Isotopes; Leg 113; Leg 208; Lower Eocene; Marine environment; Maud Rise; Microfossils; Morphology; Nannofossils; ODP Site 1262; ODP Site 1263; ODP Site 690; Ocean Drilling Program; Paleocene; Paleocene-Eocene Thermal Maximum; Paleoclimatology; Paleoecology; Paleoenvironment; Paleogene; Plantae; South Atlantic; Southern Ocean; Stable isotopes; Stratigraphic boundary; Tertiary; Upper Paleocene; Walvis Ridge; Weddell Sea
Coordinates: S650938 S650937 E0011218 E0011218
S283200 S271100 E0024700 E0013400
Record ID: 2010044886
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands