Paleogene time scale miscalibration:Evidence from the dating of the North Atlantic igneous province

David William Jolley, B. Clarke, S. P. Kelley

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46 Citations (Scopus)

Abstract

Igneous activity in the North Atlantic igneous province began with the arrival of the proto-Iceland plume beneath the lithosphere in early Cenozoic time. Sediments between and equivalent to the oldest lavas contain an influx of a diagnostic pollen flora, an influx of the dinocyst Apectodinium, a benthic foraminiferal extinction, nannofossil zone NP9, and a carbon isotope excursion associated with the late Paleocene thermal maximum (LPTM). Lavas immediately overlying the LPTM strata (54.98 Ma on the current time scale), yield U-Pb and Ar-Ar isotopic dates between 57.5 and 60.54 Ma, highlighting a dating discrepancy of up to 5 m.y. Recognition of this disparity, as well as our biostratigraphical correlation, places the LPTM within the early phase of widespread northeast Atlantic margin basaltic volcanism. A later volcanic phase, equivalent to the seaward-dipping reflector series, terminates at 54 Ma. The onset of 60 Ma basaltic volcanism can be linked to ocean water mass perturbations, and the release of ocean-floor methane hydrates thought responsible for the LPTM.

Original languageEnglish
Pages (from-to)7-10
Number of pages3
JournalGeology
Volume30
Issue number1
DOIs
Publication statusPublished - Jan 2002

Keywords

  • North Atlantic
  • Iceland plume
  • late Paleocene thermal maximum
  • Cenozoic time scale
  • AR-40-AR-39 GEOCHRONOLOGY
  • EAST-GREENLAND
  • TRANSITION
  • CHRONOLOGY
  • PALEOCENE

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