Original paper

A new Pliocene biostratigraphy for the northeastern North Atlantic

Anthonissen, Erik D.


This study has aimed to integrate and improve upon the existing marine biostratigraphic schemes pertaining to the Lower to mid-Pliocene (ca. 5.3-2.4 Ma) in the northeastern North Atlantic ('Nordic Atlantic') region. This has been achieved through: the updating of age calibrations for key microfossil bioevents, identification of new events, and integration of new biostratigraphic data from a foraminiferal analysis of cored wells and outcrops in the North Sea region. At these high latitudes, where standard zonal markers are often absent, integration of microfossil groups significantly improves temporal resolution. A new multi-group microfossil zonation is presented comprising 7 Nordic Pliocene (NP) Zones. Zonal duration ranges from 300,000 to 600,000 years. A total of 51 bioevents (28 foraminifers and bolboforms; 17 dinoflagellate cysts and acritarchs; 6 marine diatoms) facilitates zonal identification throughout the Nordic Atlantic region. Via correlations to the bio-magnetostratigraphy and oxygen isotope records of Ocean Drilling Program and Deep Sea Drilling Project Sites, the ages of shallower North Sea deposits have been better constrained. The Early to Mid-Pliocene is biostratigraphically characteristic in being the last time a significant influx of a temperate to subtropical planktonic foraminiferal fauna and dinoflagellate flora was present at such high latitudes in the Nordic and North Seas.