Paleocene to early Eocene paleoceanography of the Middle East: The δ13C and δ18O isotopes from foraminiferal calcite

Abstract

Paleocene to early Eocene benthic foraminiferal δ13C and δ18O records from southern Tethyan sections at Ben Gurion, Israel (paleodepth 500-700 m), and Gebel Aweina, Egypt (paleodepth 150-200 m), show generally similar trends but 1-3‰ more negative values than coeval deep-sea isotopic records. In both Tethyan sections a negative δ13C excursion of 2.5-3‰ marks the benthic extinction event in the latest Paleocene. For at least 1 m.y. after this event, δ13C values were 1.5-2‰ more negative on the shelf than at upper bathyal depths, reflecting a deepening of the oxygen minimum zone, possibly related to an increase or spatial shift in upwelling. Benthic δ18O records indicate a 2-4°C temperature gradient between the shelf and upper bathyal depths. Temperature-salinity reconstructions suggest that upwelling was a dominant mechanism for surface water formation in this part of the southern Tethys during the late Paleocene.