Mise en place de la circulation au Pacifique central équatorial et des assemblages des nannofossiles calcaires au Néogène (Leg DSDP 85); II, Influence de l'émersion de l'isthme de Panama, entre 7 et 2 Ma  [Establishment of Equatorial Pacific water circulation and of calcareous nannofossil assemblages during the Neogene (DSDP Leg 85); II, The uplift of the Isthmus of Panama and its consequences between 7 and 2 Ma]

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doi: 10.2113/gssgfbull.III.4.731
Alternate Title(s): Establishment of Equatorial Pacific water circulation and of calcareous nannofossil assemblages during the Neogene (DSDP Leg 85); II, The uplift of the Isthmus of Panama and its consequences between 7 and 2 Ma
Author(s): Pujos, Annick
Author Affiliation(s): Primary:
Université de Bordeaux I, Département Géologie Océanographie, Talence, France
Volume Title: Bulletin de la Société Géologique de France
Source: Bulletin de la Société Géologique de France, 3(4), p.731-736. Publisher: Société Géologique de France, Paris, France. ISSN: 0037-9409 CODEN: BSGFAE
Note: In French with English summary. 31 refs.; illus., incl. sketch maps
Summary: Four sites were drilled during DSDP Leg 85 in the equatorial Pacific. Calcareous nannofossils from Mio-Pliocene sediments recovered from the central and eastern parts of the high-productivity area were studied in detail. Two main geologic events occurred during the Neogene which modified the water masses circulation in the Pacific Ocean: (1) between 15 and 7 Ma, Antarctic glaciation influenced greatly the Pacific circulation (first part of the study); (2) between 7 and 2 Ma, the progressive uplift of the isthmus of Panama gave rise to a tropical and an equatorial upwelling, which changed the distribution of discoasters and Coccolithus pelagicus, and triggered off the recent Pacific circulation.
Year of Publication: 1987
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Algae; Assemblages; Biostratigraphy; Calcareous composition; Cenozoic; Central America; Deep Sea Drilling Project; East Pacific; Equatorial Pacific; IPOD; Leg 85; Microfossils; Nannofossils; Neogene; North Pacific; Northeast Pacific; Ocean circulation; Pacific Ocean; Paleoenvironment; Panama; Plantae; Reconstruction; Tertiary; Uplifts
Coordinates: N002954 N055100 W1135030 W1332010
Record ID: 2012069644
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