Biostratigraphy and Paleoecology of the Maastrichtian-Ypresian benthic foraminifera from El Hasana area, Central Sinai, Egypt

The Maastrichtian Ypresian benthic foraminifera were studied from three sections spanning Maastrichrian-Ypresian in El Hasana area, Central Sinai, Egypt, to infer the biostratigraphic and paleoecologic changes across the Cretaceous/Paleogene (K/Pg) and Paleocene/Eocene (P/E) boundaries. Five bench ic assemblages were recognized representing the Maastrichtian-Ypresian interval. The Maastrichtian benthic assemblage (MBA) is represented by the Bolivinoides draco draco - Spiroplectinella knebeli assemblage, while the Spiroplectinella dentata subdentata - Lagena hispida assemblage characterizes the Dan ian benthic assemblage (DBA). Also, the Anomalinoides rubiginosa - Spiroplectinella dentata intermedia assemblage characterizes the Selandian benthic assemblage (SBA) and the Vulvulina colei colei - Spiroplectinella dentata dentata assemblage distinguishes the Thanetian benthic assemblage (T BA). Finally, the Ypresian benthic assemblage (YBA) is represented by the Spiroplectinella dentata dentate - Loxostomoides applini assemblage. The paleoenvironmental conditions deduced from the study of paleoecologic parameters provide an outer shelf environmental condition during the deposition of the Maastrichtian, while during Danian/Selandian (lower and middle parrs of Esna Shale) they provide a sudden increase in the sea water depth suggesting a continental slope environment. On the other hand, the Thanetian/Ypresian succession (the upper part of Esna Shale and the lower parr of Egma Formation) was subjected to a decrease in the sea water depth upwardly suggesting an inner-middle shelf environment. Furthermore, the benthic assemblage were subjected to some extinction and recovery patterns through the environmental changes from middle neritic to upper bathyal across the Cretaceous/Paleogene (K/Pg) and Paleocene/Eocene (P/E) boundaries. Also, one hundred sixteen benthic species were recognized, photographed and taxonomically revised.

Automated summary

This study investigates the benthic foraminifera of the Maastrichtian-Ypresian interval in El Hasana area, Central Sinai, Egypt, to understand the biostratigraphic and paleoecologic changes across the K/Pg and P/E boundaries. It identifies five benthic assemblages and deduces paleoenvironmental conditions and extinction/recovery patterns.