Integrated lithostratigraphic and biostratigraphic data of two well-exposed Maastrichtian–Pa le oc en e s uc ce ss io ns , n am el y, t he Owina and the Abu Minqar sections (Dakhla Oasis, Western Desert, Egypt), led to enhance the age resolution and shed lights on the paleoenvironmental conditions throughout the deposition of the investigated sequences. The integrated biostratigraphic data
provide eight calcareous planktonic zones (five planktonic foraminifera, and three calcareous nannofossil zones) cover the studied interval. The paleoenvironmental setting of the Maastrichtian interval which represented by the lower Kharga Shale
unit ( Micula murus and Gansserina gansseri calcareous plankton zones) reveals shallow marine environmental conditions of innerneriticprobablyofmarginalsetting with highorganic matterinfluxand low-oxygenlevelinterruptedbysometransgressive
phases. While, shallower marine conditions associated with a sea-level drop mark the Cretaceous/Paleogene (K/Pg) boundary. The lowermost part of the Paleocene interval (NP3, NP4, P1b, P1c, and P2 calcareous plankton zones) which covered the lower partof the upper KhargaShale unitis markedby middle-outerneritic depositional setting,well-oxygenated seawater, aswell as a low organic matter influx coupled with relative sea-level rise. Above this level until reach the base of the Tarawan Formation, a major drop in the sea-level is observed. This interval is marked by absence of the calcareous planktonic taxa. Only agglutinated foraminiferal taxaare recordedduringthisinterval. While the TarawanFormation (P4bplanktonicforaminiferal Zone) is marked by outer neritic depositional setting that represents a sea-level transgressive phase. According to the field observations and the presence/absence of the calcareous planktonic zonal marker species; two tectonic events are detected. The tectonic event I took place at the K/Pg boundary and resulted in a significant hiatus at the studied area. Tectonic event II is observed at the contact between the Dakhla and the Tarawan formations across the Danian–Selandian transition. It is evidenced by the existence of an erosive (irregular) surface at the basal part of the Tarawan Formation. These events could be attributed to the echo of the Syrian Arc tectonism which interrupted the global sea-level curve throughout the Maastrichtian–Paleocene time.