Israel Journal of Earth Sciences vol:44 pages:207-222
We investigated the benthic foraminiferal record of the neritic sequence at Gebel Aweina (Nile Valley, Egypt) in relation to the latest Paleocene deep-sea benthic extinction event (BEE). At Gebel Aweina an expanded sequence, spanning calcareous nannofossil Zones NP8-NPlO, is continuously exposed and yields calcareous microfauna throughout. The BEE level is situated about halfway through Zone NP9 at 17m above the base of the Esna Formation. Detailed biostratigraphic and isotopic studies have indicated that the sequence is (nearly?) complete across the upper Paleocene lower Eocene and, like elsewhere in Egypt and around the Mediterranean, the lowest common occurrence of the planktonic marker Globanomalina luxorensis coincides with the benthic foraminiferal extinction and the carbon isotopic excursion. Some fifteen benthic taxa disappeared at the same level, amongst them taxa that became globally extinct, such as Angulogavelinella avnimelechi, Coryphostoma midwayensis. Neoeponides lunata, and Neoflabellina jarvisi. Due to outer neritic (150-200 m; slightly deeper during late Biochron NP8) depositional conditions, deepsea taxa such as Bulimina trinitatensis, Gavelinella beccariiformis, and Gyroidinoides globosus yield only scattered occurrences in a few samples. Despite a number of new appearances, the post-BEE assemblages (in total, 70 different taxa, about 40 per sample) remain impoverished relative to pre-BEE assemblages (in total, 91 taxa, about 55 per sample). The Gebel Aweina sequence provides strong evidence that the latest Paleocene BEE cannot be considered as a turnover that affected deep-sea benthic foraminifera faunas exclusively; simultaneously, outer neritic faunas experienced a punctuated, though less severe, evolutionary turnover.