Gravity-based structural mapping of the southern Benue Trough, Nigeria

This study presents a gravity-based structural map of the southern Benue Trough in Nigeria, employing various edge enhancement techniques. The spectrum analysis is used to isolate anomalies of interest from Bouguer gravity data. The filtered anomaly map is then interpreted using derivative-based techniques, specifically the total horizontal gradient, theta map, normalized horizontal gradient, tilt angle of the total horizontal gradient, total horizontal gradient-based edge detector, and the Euler deconvolution to delineate tectonic and geological structural features and their depths. The analysis reveals that the region is characterized by N-S and NE-SW trending lineaments. The NE-SW trending features align with the tectonic framework of the Benue Trough and are likely to have been rejuvenated during the Cretaceous period, while the N-S structures in the western part may be influenced by underlying faults. These structural features show a good correlation with the Euler deconvolution map demonstrating the variation of the source depths (from 1 to 6.4 km). This study provides an updated structural map, elucidating the interconnection between the gravity-based structural map and the tectonic setting of the southern Benue Trough.