Nannofossil assemblage fluctuations during the Paleocene-Eocene thermal maximum at Sites 213 (Indian Ocean) and 401 (North Atlantic Ocean); palaeoceanographic implications

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doi: 10.1016/j.marmicro.2004.04.002
Author(s): Tremolada, Fabrizio; Bralower, Timothy J.
Author Affiliation(s): Primary:
University of Milan, Dipartimento di Scienze della Terra, University Park, PA, United States
Other:
University College London, United Kingdom
Pennsylvania State University, Italy
Volume Title: Calcareous nannofossil palaeoecology and palaeoceanographic reconstructions
Volume Author(s): Villa, Giuliana, editor; Lees, Jackie A.; Bown, Paul R.
Source: Marine Micropaleontology, 52(1-4), p.107-116; Ninth international Nannoplankton Association conference, Parma, Italy, Sept. 9-12, 2002, edited by Giuliana Villa, Jackie A. Lees and Paul R. Bown. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0377-8398 CODEN: MAMIDH
Note: In English. 55 refs.; illus., incl. strat. cols., sketch map
Summary: The Paleocene-Eocene Thermal Maximum (PETM) was an abrupt global warming event at ∼55 Ma. This event had profound effects on the biosphere. Quantitative investigations of calcareous nannofossil assemblages were performed across the PETM, at Deep Sea Drilling Project Site 213, in the tropical Indian Ocean, and Site 401, in the Bay of Biscay, North Atlantic Ocean, at a temperate latitude. Calcareous nannofossil assemblages from both sites show major changes before, during, and after the PETM. Fluctuations at Site 213 are affected by selective dissolution of the least robust taxa. By contrast, assemblages in the lower part of the PETM at Site 401 show less diagenetic alteration and display high abundances of genera such as Discoaster, Fasciculithus, and Ericsonia. These taxa reflect relatively warm and, probably, oligotrophic surface waters. Abundances of the genus Chiasmolithus, an indicator of relatively cool and eutrophic waters, decreased dramatically. The upper portion of the PETM is characterized by an increase in the abundance of Toweius spp. and Zygrhablithus bijugatus, interpreted as a return to cooler and more eutrophic conditions. The elimination of Fasciculithus was probably due to competition with the holococcolith species, Z. bijugatus, which occupied the same ecological niche. The occurrences of long-armed and asymmetrical Discoaster species such as Discoaster araneus, Discoaster anartios, and Discoaster okadai, and Rhomboaster species, such as Rhomboaster calcitrapa and Rhomboaster cuspis, are characteristic of the PETM interval. Abstract Copyright (2004) Elsevier, B.V.
Year of Publication: 2004
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Algae; Aliphatic hydrocarbons; Alkanes; Assemblages; Atlantic Ocean; Cenozoic; DSDP Site 213; DSDP Site 401; Deep Sea Drilling Project; Eocene; Gas hydrates; Hydrocarbons; IPOD; Indian Ocean; Leg 22; Leg 48; Lithostratigraphy; Marine environment; Methane; Nannofossils; North Atlantic; Organic compounds; Paleocene; Paleoclimatology; Paleoecology; Paleoenvironment; Paleogene; Plantae; Productivity; Quantitative analysis; Tertiary
Coordinates: S101243 S101242 E0935347 E0935346
N472538 N472540 W0084837 W0084838
Record ID: 2005076120
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands