Late Pliocene and Pleistocene biostratigraphy of the Nordic Atlantic region
Anthonissen, Erik D.
published: Jul 23, 2008
ArtNo. ESP026004301006, Price: 29.00 €
The lack of primary and secondary GSSP correlative markers in Plio-Pleistocene deposits of the North Sea, Nordic seas and northern North Atlantic creates a challenge for the biostratigrapher. This study highlights the closest biostratigraphic approximations in this region to the standard chronostratigraphic boundaries of the Gelasian Stage and Lower, Middle and Upper Pleistocene. Via correlations to key Ocean Drilling studies and unambiguous magnetostratigraphies in the region, the age of shallower deposits of the North Sea has been better constrained. The closest biostratigraphic approximations to these chronostratigraphic boundaries in the region are presented, together with a framework of calibrated events according to sub-basin. The best approximating boundary events at any given location in this region depends upon both the paleoceanographic and paleobathymetric settings. In the Nordic Atlantic region only three GSSP correlative marker events have been identified in the 15 Ocean Drilling Program sites discussed. At lower neritic to bathyal water depths, the first common occurrence of Neogloboquadrina pachyderma (sinistrally-coiled morphotype) allows for direct correlation with the base Pleistocene GSSP in Italy. The occurrence of the benthic foraminifer Cibicides grossus appears to have been bathymetrically controlled, with a youngest stratigraphic occurrence at upper bathyal depths. At lower neritic depths in the central and northern North Sea the last occurrence of C. grossus coincides with the base of the Pleistocene. Diachroneity of a number of Nordic high-latitude bioevents may be primarily due to differences in surface water masses and paleobathymetry.