An Integrated Geophysical Approach for Estimating the Depth of Mineral Potential in Some Part of Basement Complex Terrain Southwestern Nigeria

Effective mineral exploration in a basement complex necessitates precise delineation of overburden thickness and mineral potential within the Basement Complex terrain. This study examined the subsurface geology and assesses the abundance of prospective mineral deposits within the study area The objective of the study was to outline the overburden thickness and infer mineral potential using integrated ground magnetic and electrical resistivity geophysical methods. The electrical resistivity method unraveled the litho-stratigraphic sequence as surmised from geo-electric layers. Consequently, the mineralization of the basement delineated was characterized by the magnetic method. The acquired data were processed using WINRESIST and Oasis Montaj respectively. The electrical resistivity method provided detailed litho-stratigraphic information, revealing geo-electric layers corresponding to the topsoil (302 – 933 Ωm), weathered layer (48 –181 Ωm), and bedrock (421–1357 Ωm), with overburden thicknesses ranging between 7.62 m and 9.5 m. Ground magnetic data further characterized the basement mineralization, identifying three distinct magnetic anomalies: a null anomaly district (-3 – 3 nT), a weak positive anomaly (7.3–12.4 nT), and a magnetic closure (17.7 – 22 nT). Magnetic source depths varied between 1 m and 14 m, with low magnetic susceptibility indicative of porphyritic granite with quartz phenocrysts. In conclusion, the findings are particularly favorable for quarrying operations in the northern sector of the study area, where granite abundance is estimated at around 68%, indicating strong economic potential. This integrated approach of electrical and magnetic geophysical methods, described the accuracy of subsurface mapping by simultaneously resolving overburden thickness and inferring mineral potential in a Basement Complex terrain.