The biostratigraphy and paleobiology of Oligocene planktonic Foraminifera from the equatorial Pacific Ocean (ODP Site 1218)

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doi: 10.1016/j.marmicro.2006.08.005
Author(s): Wade, Bridget S.; Berggren, William A.; Olsson, Richard K.
Author Affiliation(s): Primary:
Rutgers State University of New Jersey, Department of Geological Sciences, Piscataway, NJ, United States
Volume Title: Marine Micropaleontology
Source: Marine Micropaleontology, 62(3), p.167-179. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0377-8398 CODEN: MAMIDH
Note: In English. With appendix available online. 41 refs.; illus., incl. 2 plates, sketch map
Summary: Planktonic foraminifera from a continuous Oligocene succession with clear magnetochronology and sediment cycles at Ocean Drilling Program Site 1218 (equatorial Pacific Ocean) were studied in the interval from 27 to 30 Ma. Paragloborotalia taxa are common and we examined their size, relative abundance, and stable isotopes. Multispecies stable isotope data indicate the depth habitats of Oligocene planktonic foraminifera and suggest that "Globoquadrina" venezuelana and Dentoglobigerina globularis were probably mixed-layer dwellers, with paragloborotaliids recording heavier δ18O signatures consistent with a thermocline habitat. Cyclic variations in the abundance of Paragloborotalia match eccentricity (100 kyr) variations in percent carbonate and δ13C, suggesting orbitally forced upwelling in the equatorial Pacific Ocean and that Paragloborotalia were responding directly to changes in surface water productivity. The high-resolution biostratigraphy calibrated to the magnetochronology constrains the extinction of Paragloborotalia opima which marks the top of Planktonic Foraminifera Biozone O5 (P21b) at 27.456 Ma. The highest occurrence of P. opima is associated with a 50% size decrease in Paragloborotalia pseudocontinuosa taxa within Chron 9n. In addition, we find the extinction of Chiloguembelina cubensis is consistent with other deep-sea sections within Chron 10n at 28.426 Ma marking the O4/O5 (P21a/P21b) boundary. Abstract Copyright (2007) Elsevier, B.V.
Year of Publication: 2007
Research Program: ODP Ocean Drilling Program
Key Words: 10 Paleontology, Invertebrate; 12 Stratigraphy, Historical Geology and Paleoecology; Biostratigraphy; Biozones; C-13/C-12; Carbon; Cenozoic; Deep-sea environment; Dentoglobigerina; Equatorial Pacific; Foraminifera; Globoquadrina; Habitat; Invertebrata; Isotope ratios; Isotopes; Leg 199; Marine environment; Marine sediments; Microfossils; Morphology; O-18/O-16; ODP Site 1218; Ocean Drilling Program; Oligocene; Oxygen; Pacific Ocean; Paleo-oceanography; Paleobiology; Paleocirculation; Paleoecology; Paleogene; Paragloborotalia; Planktonic taxa; Protista; Sediments; Size; Stable isotopes; Tertiary; Thermocline
Coordinates: N085300 N085300 W1352200 W1352200
Record ID: 2008070698
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands