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• The early syn -rift marine deposits of the Gulf of Suez has an early Miocene age. • Our data contradict earlier interpretations of marine flooding as early as late Oligocene. • Acquitanian/Burdigalian and Burdigalian/Langhian boundaries are recorded within the succession. • New bioevents are regarded as reliable for age assignment in the Gulf of Suez. • The FO of Gs. subquadratus is a main event for the subdivision of Burdigalian. • The early Miocene fossil assemblage in the Suez rift has a Mediterranean affinity. The absence or rarity of some global marker taxa in the semi-restricted Suez rift basin has led to uncertainty with respect to the age of the early syn -rift deposits. To tackle this issue, high-resolution foraminiferal and calcareous nannofossil biostratigraphy was undertaken on sections in the Wadi Baba area at the eastern basin margin. Two planktic foraminiferal bioevents of early Miocene age are recognized: First Occurrences (FOs) of Globigerinoides subquadratus and Trilobatus sicanus. These bioevents define three zones/subzones: MMi2b, MMi2c-MMi3 and MMi4. Calcareous nannofossil analysis provided the basis for the definition of three zones: CNM4 to CNM6 based on FOs of Helicosphaera ampliaperta and Sphenolithus belemnos , and the first common occurrence of S. heteromorphus. Our results assign a new age estimate of late Aquitanian to early Burdigalian (<19.01 Ma) for the Nukhul Formation, and Burdigalian to early Langhian for the Rudeis Formation, with three possible hiatuses. Integration of benthic foraminiferal biofacies, lithofacies and nannofossil paleoecological markers reveals a broad range of paleoenvironments, from shoreface to upper bathyal. The Nukhul Formation was deposited in nearshore, nutrient-rich, well-oxygenated conditions. Deeper water environments of neritic to upper bathyal prevailed during the Rudeis Formation. Comparison with coeval deposits in the offshore area of the basin reveals significant paleoenvironmental variability during the Burdigalian associated with episodic subsidence along basinal faults. Climate-sensitive taxa and oxygen isotope data indicate a prevalence of warm paleoclimatic conditions. Our results suggest the development of a seaway connecting the Gulf of Suez with the Mediterranean during the early Miocene rather than Chattian. [ABSTRACT FROM AUTHOR]

The Abu Qada Formation is a reference interval for the Cenomanian–Turonian boundary event in the northeastern margin of Africa. In this paper, geochemical, biostratigraphical, and carbon isotope ratio studies are presented using high-resolution well data yielded from the Gulf of Suez, Egypt to evaluate the paleoenvironmental condition, sequence stratigraphy and source rock potential of the Upper Cenomanian/Lower Turonian Abu Qada Formation. A total of 12 core samples and 4 ditch cuttings were collected from OCT-A8St1 well in the October Oil Field for geochemical, palynological and calcareous nannoplankton analyses. Cyclostratigraphic analysis was prepared to characterize the electrofacies change along the Cenomanian/Turonian boundary interval including the Oceanic Anoxic Event 2 (OAE2). The Predictive Error Filter Analysis (PEFA) patterns and Integrated Predictive Error Filter Analysis (INPEFA) curves found 3rd order cycle of the OAE2 within the global third-order cycle Ce5. A stable carbonate isotope analyses with total organic carbon (TOC) resulted in a remarkable positive excursion δ13C carb (3.67‰) associated with change in the TOC content. The quantitative analysis of calcareous nannofossils indicates the high productiveness of nannoplankton around the Cenomanian/Turonian boundary interval. The high abundance of the Discorhabdus genus proves the paleoenvironmental change during the OAE2 interval. The palynofacies interpretation indicates the lower part of Abu Qada Formation to be deposited in a slightly reducing conditions at the inner neritic setting, while the upper part of Abu Qada to lower part of Wata formations were deposited in deeper marine setting under anoxic conditions. These changes in the overall depositional conditions are documented by the remarkable change in palynofacies and organic carbon content (TOC). Dark gray shale and carbonate sediments are interpreted to be a good source rock potential by kerogen quantified palynofacies analysis indicating oil and gas prone producing materials (Kerogen types II and II/III). The best source rock quality is associated with the Abu Qada Formation's OAE2 record. These criteria allow us to identify the occurrence of OAE2 record in the Gulf of Suez petroleum province as a useful tool for high-resolution chronostratigraphic analysis. • The occurrence of OAE2 record in the Gulf of Suez petroleum province is identified as a useful tool for high-resolution chronostratigraphic analysis. • The upper part of Abu Qada to lower part of Wata formations were deposited in deeper marine setting under anoxic conditions. • The quantitative analysis of calcareous nannofossil indicates the high productiveness of nannoplankton around the Cenomanian/Turonian boundary interval. • The quantitative analysis of calcareous nannofossil indicates the high productiveness of nannoplankton around the Cenomanian/Turonian boundary interval. [ABSTRACT FROM AUTHOR]