Foraminiferal variations and stratigraphic implications to the deposition of sapropel S5 in the eastern Mediterranean

Abstract

Detailed study of the temporal and spatial patterns of planktonic foraminiferal assemblages was performed on seven eastern Mediterranean deep-sea cores to evaluate differences and similarities in their stratigraphic records during the Eemian sapropel S5 interval. Changes in the succession of planktonic assemblages are very similar in all investigated sapropel S5 sequences. Analyses carried out on the 63 and 150 μm size fractions indicate that during this time interval, size does not significantly affect the stratigraphic patterns. Benthic assemblages were studied at three sites, where their succession of changes was concordant but locally different. In this framework, comparison of S5 sapropels layers from different areas of the eastern Mediterranean suggests that the onset of the dark colour does not occur in the same stratigraphic position at a regional scale, whereas the absence/drastic reduction of benthic foraminifera within sapropel intervals appears to be a “time equivalent” event and corresponds to the last local occurrence of Globorotalia inflata.