Quantitative foraminiferal and palynomorph biostratigraphy of the Paleogene in the southwestern Barents Sea

• Main Authors: Nagy, J., Kaminski, M.A., Gradstein, F.M., Johnson, K. , K.
• Other Authors: Bubik, M.
• Format: Report
• Language: English
• Published: Grzybowski Foundation 2004
• Subjects: Barents Sea; Labrador Shelf; Rugosa
• Online Access: https://discovery.ucl.ac.uk/id/eprint/14126/1/14126.pdf; https://discovery.ucl.ac.uk/id/eprint/14126/

The stratigraphic distribution of both foraminifera and dinoflagellate cysts is recorded from the Paleocene to Eocene Torsk Formation in 12 petroleum exploration wells drilled in the southwestern Barents Sea. The foraminiferal assemblages are wholly agglutinated, and are referred to outer shelf to middle bathyal environments. A quantitative analysis of biostratigraphic events, mainly last occurrences (first downhole occurrences), is performed by means of the Ranking and Scaling (RASC) program. This procedure combined with conventional stratigraphic treatment has enabled us to establish the most likely order of microfossil events, and to propose a new quantitative zonal scheme for the southwestern Barents Sea. In the studied wells the following six zones and subzones are distinguished (in ascending order): BSP 1, Psmmosphaera fusca – Hyperammina rugosa, late early to early late Paleocene; BSP 2, Spiroplectammina spectabilis early late Paleocene; BSP 3A, Reticulophragmium pauperum, middle late Paleocene; BSP 3B, Haplophragmoides aff. eggeri, latest Paleocene; BSP 4, Spiroplectammina navarroana, earliest Eocene; BSP 5, Reticulophragmium amplectens, early to middle Eocene. Owing to the occurrence of cosmopolitan deep-water agglutinated foraminifera, the new zonal scheme compares well with previous zonations developed for the Paleogene of the mid-Norwegian shelf, the North Sea and Labrador Shelf.