Mapping the structural configuration of the western Gulf of Guinea using advanced gravity interpretation methods

The western Gulf of Guinea has important implications for seismic-hazard estimates of the adjoining sub-Sahara West Africa region because of the presence of four active transform faults, namely the St. Paul, Romanche, Chain and Charcot fault zones. A satellite gravity data analysis was performed over the western Gulf of Guinea to delineate the structural configuration of the area. Initially, the energy spectrum analysis was used to determine regional and residual gravity effects. Further, the advanced techniques such as the tilt angle of the gradient amplitude (TAHG), the improved horizontal tilt angle (ITDX), the enhanced gradient amplitude (EHGA), and the fast sigmoid-based edge detection filter (FSED) were applied to the residual gravimetric anomaly to extract lineaments of the western Gulf of Guinea. The major trend of the detected lineaments has an ENE-WSW direction and depths of the gravity sources range from 3.4 to 13 km corresponding to widespread altered basalt, breccia, serpentinized peridotite and minor gabbro. Our findings closely agree with known information but are also able to confirm the presence of various other structures. Our results thus provide a structural map that helps us to have a better understanding of the tectonic and structural framework of the western Gulf of Guinea.