Cyclic changes in Turonian to Coniacian planktic foraminiferal assemblages from the tropical Atlantic Ocean

Oliver Friedrich, Richard D. Norris, Andre Bornemann, Britta Beckmann, Heiko Paelike, Paula Worstell, Peter Hofmann, Thomas Wagner

Research output: Contribution to journalLiterature review

13 Citations (Scopus)

Abstract

Abundance patterns of planktic and benthic foraminifera from a tropical Atlantic drill site (Ocean Drilling Program Site 1259, Demerara Rise, Suriname margin) display a pronounced 400 kyr cyclicity, uninterrupted throughout our similar to 87.8-92 Ma record, between two clearly distinguishable assemblages: (1) a pelagic foraminifer fauna, which represents a deep oxygen minimum zone, and (2) another assemblage representing a shallow oxygen minimum zone where the foraminifer fauna is dominated by a higher diversity population of mostly small clavate and biserial species common in epicontinental seas. The cyclic changes in the long eccentricity band (400 kyr) between these two assemblages are proposed to reflect changes in the mean latitudinal position of the Intertropical Convergence Zone (ITCZ). Associated fluctuations in precipitation and trade wind strength may have influenced the upwelling regime at Demerara Rise leading to the observed cyclicity of planktic foraminiferal assemblages. The severe Turonian to Coniacian paleoclimatic and paleoceanographic changes in the Atlantic Ocean (e.g., gateway opening, cooling, and glaciation), however, seem to have no influence on the composition of tropical planktic foraminiferal faunas. There is no apparent relationship between foraminifer abundances and a major deflection in the stable isotope record interpreted elsewhere as a sign of the growth and decay of a large polar ice sheet.

Original languageEnglish
Pages (from-to)299-313
Number of pages15
JournalMarine Micropaleontology
Volume68
Issue number3-4
DOIs
Publication statusPublished - Aug 2008

Keywords

  • Cretaceous
  • planktic foraminifera
  • Atlantic ocean
  • Demerara Rise
  • Turonian
  • Ocean Drilling Program
  • SEA-SURFACE TEMPERATURE
  • ODP LEG 159
  • ISOTOPIC EVIDENCE
  • STABLE-ISOTOPE
  • HIGH-RESOLUTION
  • SOUTH-AMERICA
  • DEMERARA RISE
  • DISTRIBUTION PATTERNS
  • DEPTH STRATIFICATION
  • CRETACEOUS CLIMATE

Cite this

Friedrich, O., Norris, R. D., Bornemann, A., Beckmann, B., Paelike, H., Worstell, P., Hofmann, P., & Wagner, T. (2008). Cyclic changes in Turonian to Coniacian planktic foraminiferal assemblages from the tropical Atlantic Ocean. Marine Micropaleontology, 68(3-4), 299-313. https://doi.org/10.1016/j.marmicro.2008.06.003