Sedimentological, Diagenetic, Petrophysical Controls on the Miocene Submarine Deposits, Gulf of Suez: Implications for Reservoir Quality

Abstract

Abstract The Gulf of Suez Miocene ASL Member is an important reservoir for hydrocarbon development. This study specifically focused on the sedimentological, diagenetic, and petrophysical characteristics to better delineate the reservoir quality variability. The data comprised of well logs from four (4) wells, two of which had whole core with a total length of 150 ft. About 65 rock samples were selected and made into thin sections. These thin sections were examined under a polarizing microscope to observe mineralogical composition and diagenetic evolution. X-Ray diffraction (XRD), scanning electron microscope (SEM), and core plug porosity and permeability analysis were performed and used to interpret the mineralogical composition, pore throat geometries, and pore system characteristics of the reservoir zone. The comprehensive analysis showed that the ASL Member was deposited as turbidities and gravity flows in a submarine fan system. Two closer siliciclastic sources, Wadi Baba and Wadi Feiran, are interpreted to be potential sediment sources that fed coarser siliciclastic material via submarine canyons and relay ramps between extensional faults. The petrophysical measurements showed clear reservoir heterogeneity with a range of porosities between 2 to 10 %, and permeabilities between 0.4 and 60 mD. The reservoir quality is influenced by sedimentation and diagenesis, which play a major role in enhancing or reducing the reservoir quality. Combining the sedimentological and petrophysical analysis will help identify sweet spots by delineating high quality reservoir fairways. The presented work provides a reference for depositional, diagenetic, and petrophyiscial controls on submarine fan depositional systems in the studied basin and elsewhere.