Calcareous plankton dissolution pattern and coccolithophore assemblages during the last 600 kyr at ODP Site 1089 (Cape Basin, South Atlantic); paleoceanographic implications

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doi: 10.1016/S0031-0182(03)00467-X
Author(s): Flores, José-Abel; Marino, Maria; Sierro, Francisco J.; Hodell, David A.; Charles, Christopher D.
Author Affiliation(s): Primary:
Universidad de Salamanca, Departamento de Geología, Salamanca, Spain
Other:
Universita di Bari, Italy
University of Florida, United States
Scripps Institution of Oceanography, United States
Volume Title: Palaeogeography, Palaeoclimatology, Palaeoecology
Source: Palaeogeography, Palaeoclimatology, Palaeoecology, 196(3-4), p.409-426. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0031-0182 CODEN: PPPYAB
Note: In English. Includes appendix. 64 refs.; illus., incl. 1 table, sketch map
Summary: Coccolithophore assemblages at ODP Site 1089 in the southern Cape Basin (∼41°S) were used to reconstruct surface-water conditions for the late Quaternary (Marine Isotope Stages (MIS) 1-15) in a region of strong hydrographic gradients in the southeast Atlantic. Stratigraphic control was provided by oxygen isotope stratigraphy and calcareous nannofossil events that are thought to be synchronous over a broad range of latitudes. The greatest coccolith abundances occurred at glacial terminations and, to a lesser degree, during glacial stages. Conversely, coccolithophores were the least abundant during the transition between interglacial to glacial stages, when calcium carbonate dissolution was strong. With the exception of these intervals, coccolith preservation is moderate to good, allowing study of the assemblages. The total abundance of coccolithophores and calcium carbonate variations at Site 1089 result both from variations in dissolution and carbonate production. During terminations, for example, the greatest calcium carbonate concentrations occurred at the same time as a moderate-to-poor preservation of coccoliths and foraminifers. Carbonate production was relatively high during these intervals. However, during terminations IV and V, maxima in carbonate production in the ocean were linked to high-dissolution processes at Site 1089. This trend is not observed for terminations I, II and III [Hodell et al., Earth Planet. Sci. Lett. 192 (2001) 109-124]. The interval from MIS 9 to 13 is coincident with high abundances of highly calcified species such as Gephyrocapsa caribbeanica. Here we discuss the contribution of this ubiquitous species to the production of calcium carbonate and their paleoecological significance. Except for occasional coccolith-barren intervals during interglacial periods, subtropical coccolith species were present continuously at ODP Site 1089 during the late Pleistocene. This suggests that the Polar Front has been south of Site 1089 for the last 600 kyr. Abstract Copyright (2003) Elsevier, B.V.
Year of Publication: 2003
Research Program: ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Algae; Assemblages; Atlantic Ocean; Bioclastic sedimentation; Biostratigraphy; Calcium carbonate; Cape Basin; Cenozoic; Chemostratigraphy; Coccolithophoraceae; Coccolithus; Coccolithus pelagicus; Emiliania; Emiliania huxleyi; Glacial environment; Glaciomarine environment; Interglacial environment; Isotope ratios; Isotopes; Leg 177; Marine environment; Marine sediments; Microfossils; O-18/O-16; ODP Site 1089; Ocean Drilling Program; Oxygen; Paleo-oceanography; Paleoecology; Plantae; Pleistocene; Preservation; Quaternary; Sedimentation; Sedimentation rates; Sediments; Solution; South Atlantic; Stable isotopes; Subtropical environment; Upper Quaternary
Coordinates: S405611 S405611 E0095338 E0095338
Record ID: 2003061191
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands