Integrated Geological, Stratigraphic, Geochemical, and Petrophysical Characterization of Offshore Block 7, Mauritanian Coastal Basin: Pelican Field

Summary This study presents a comprehensive characterization of the Pelican Field, targeting deep-water turbidite reservoirs. The MSGBC Basin, a passive margin system initiated during Late Triassic rifting, hosts multiple stacked hydrocarbon-bearing intervals. Pelican-1, drilled to a total depth of 3825 mss in 1679 m water depth, encountered three distinct pressure-separated gas-condensate columns within Maastrichtian-Campanian turbidite sandstones. Petrophysical evaluation using density-neutron crossplots, corrected for shale content, indicates good porosity &water saturation in upper sands, suggesting permeability reduction due to increased surface area associated with feldspar content; permeability in the better sands is estimated around 100 mD. Formation water resistivity (0.05–0.07 Ω•m) and gas composition imply aType II/II-III source matured to ∼1.1% Ro. Vitrinite reflectance and geochemical analyses suggest Cenomanian-Turonian source rocks as the primary contributors to gas and light oil/condensate (API 40–45), with the oil window reached at ∼4250–4300 m. No regional aquifer was encountered, and source rocks within the penetrated intervals are mostly immature, though marginally better source facies occur locally. The integration of stratigraphy, petrophysics, geochemistry, and structural analysis confirms the presence of a Valid petroleum system in Block 7 and highlights the potential for hydrocarbon exploitation from Lower Palaeocene submarine channel turbidites and secondary stratigraphic targets in Cretaceous-Oligocene intervals.