Integrated Structural, Petrophysical, and Petrographic Characterization of the Chinguetti Field, Mauritanian Coastal Basin

Abstract

The Chinguetti Oil Field located offshore North West Africa, represents a structurally complex hydrocarbon system developed over a salt-cured diapir and strongly influenced by fault-driven compartmentalization. The field is a faulted domal anticline developed above an underlying salt diapir within the deepwater Mauritanian Basin. The structure is defined as a faulted domal anticline, dominated by a major east–west trending normal fault with significant throw, accompanied by radial faulting related to halo kinetic activity. These structural elements subdivide the field into distinct compartments, as evidenced by variations in fluid contacts and pressure behavior between wells. Fault seal analysis indicates that only faults with sufficient displacement contribute to effective compartmentalization, whereas smaller-scale and sub seismic faults may significantly influence fluid flow behavior. Hydrocarbon charge is linked to Cenomanian–Turonian source rocks, with migration facilitated by vertical pathways along salt domes. This study integrates 3D seismic sections with petrophysical well logs and petrography SWC data to constrain the geological framework, identify potential reservoir targets, and evaluate reservoir quality alongside the associated uncertainty and architectural complexity. The study integrates Posts TM seismic data, well-log interpretation, petrophysical analysis, and core-based petrography to characterize the structural and reservoir framework of the Chinguetti Field. Shale volume, porosity, hydrocarbon saturation, and net-to-gross were evaluated from well logs, while SWC and MSCT samples were analyzed using thin-section petrography, SEM, XRD, and grain-size analysis. The integrated workflow assesses reservoir compartmentalization, permeability uncertainty, and the influence of structural and depositional heterogeneity on reservoir quality and connectivity.