ABSTRACT: This study investigates the imprints of early Paleogene sea level changes on biostratigraphy and paleoenvironmental conditions at Gebel Falig in North Sinai. Biostratigraphic analysis has allowed the recognition of 17 planktic biozones (Pa–E5) ranging from Early Danian to Ypresian, representing continuous sedimentation despite the absence of Zone PO. Based on%P, four sea-level transgression cycles of the 3rd order have been recognized, the first cycle, spanning from Pa to P3a, is bounded by shallowing phases at the K/Pg andD/S boundaries, where sea level reached amaximum at the P1c/P2 subzonal boundary with a minor eurybathic shift in the upper part of subzone P1a. A gradual buildup of the faunal community in this cycle occurred within oligotrophic conditions. The second cycle includes subzone P3b, representing a middle neritic environment with a recovery of the benthic community and return of oligotrophic conditions. The third transgressive cycle extends from the upper part of Subzone P3b to Zone P5.Carbonate dissolution obliterated most of the benthic and planktic forms within Zone P5, but the occurrence of Kolchidina paleocenica within this interval may suggest a shallow marine environment. The Paleocene oligotrophic conditions ended abruptly with the extinction of Angulogavelinella avnimelechi at the P/E boundary. The last cycle extends from the base of Zone E1 to Zone E5. It is characterized by high %P and very low benthic diversity, which may have been due to environmental stress. It is concluded that shallowing and surface eutrophication due to upwelling are the main factors controlling the development of diagnostic Early Eocene assemblages in the study area and at other sites on the southern Tethys margin.

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