Sequence stratigraphic analysis and depositional evolution of the Upper Cretaceous deposits in Ras Budran oil field, Gulf of Suez, Egypt

The Upper Cretaceous deposits represent significant oil reservoirs in several fields of the Gulf of Suez province, Egypt. The present work aims to study these sediments in Ras Budran Oil Field in view of sequence stratigraphic analysis. Five third order depositional sequences were determined for the Upper Cretaceous section in Ras Budran Field depended on the analysis and interpretation of the integrated well logging and biostratigraphic datasets. The five sequences are separated by six sequence boundaries and were classified into their systems tracts signifying several sedimentation patterns of progradation and retrogradation. The first depositional sequence corresponds to the Cenomanian-early Turonian Raha and Abu Qada formations classifying into transgressive and highstand system tracts. The second sequence comprises the Late Turonian Wata Formation subdividing into transgressive and highstand systems tracts. The third sequence embraces the Coniacian-Santonian Matulla Formation subdividing into lowstand, transgressive and highstand systems tracts. The fourth and fifth depositional sequences coincide with the Campanian-Maastrichtian Brown limestone and Sudr Chalk marking transgressive and highstand system tracts. The well-documented Maastrichtian-Paleocene boundary marks the last sequence boundary at the top of the studied succession and is strongly controlled by synsedimentary tectonics associated with the Syrian Arc tectonism. The Late Cretaceous depositional history at Ras Budran Field was dominated by relative sea level fluctuations. The rising in relative sea level was controlled by the global sea level rise together with basin subsidence whereas; the drop in relative sea level was controlled by the basin filling