Organic facies and depositional system evolution in an Upper Cretaceous wetland setting: evidence from the Gulf of Suez, Egypt

Abstract While decades of hydrocarbon exploration in the Gulf of Suez, Egypt, have yielded valuable insights, a significant opportunity remains to improve our understanding of the Upper Cretaceous strata through palynological research. In this context, the recent access to borehole drill cores from the Wata and Matulla formations presents an excellent chance to generate new findings and address the gap created by limited studies on the Cretaceous in this region. This study aims to address the existing gaps in our understanding of Late Cretaceous palaeoenvironments within one of Egypt’s largest petroleum basins. The analysed samples are from the OCT-A8 and GS197-2 wells in the October Oil Field, offshore from the central Gulf of Suez. By integrating palynological investigations with sedimentological data, we seek to deliver a comprehensive approach that yields precise insights into the depositional environments of these challenging reservoir units. Preliminary palynological results reveal a prevalence of non-marine palynomorphs in both studied rock units. We observed a dominance of Pediastrum and a relative scarcity of palynomorphs in the Wata Formation, while water ferns dominate the palynological composition of the Matulla Formation. The palynofacies or kerogen content was dominated by phytoclasts in both rock units. This indicates deposition in a highly proximal shelf basin near aquatic areas or wetlands, a finding that is similarly supported by the sedimentological data.