Integration of Aeromagnetic, Geological, and Geochemical Techniques for Mineral Exploration in Orin-Ekiti and Its Environs, Southwestern Nigeria

The study of Orin and its surrounding areas within the Precambrian Basement Complex of southwestern Nigeria addresses the limited integration of geological, geochemical, and geophysical investigations that has constrained understanding of the region’s mineralization potential. This research integrates aeromagnetic interpretation, geological mapping, and geochemical analysis to delineate lithological boundaries, structural trends, and potential mineralized zones. Geological mapping at a 1:25,000 scale identified four main lithologies: banded gneiss, granite gneiss, charnockite, and granite. Aeromagnetic data (Sheet 244, Ado-Ekiti), processed using reduction-to-equator (RTE), first vertical derivative (FVD), analytic signal (AS), and Euler deconvolution (EUD), revealed dominant NE–SW and NW–SE structural trends. EUD results indicated mineralization zones at mesothermal depths (2,000–2,400 m), suggesting Cu, Zn, Au, Ag, and Pb occurrences. Petrographic analysis showed high quartz (62.11–78.34 wt%) and moderate plagioclase (10.04–21.02 wt%), reflecting acidic magmatic crystallization. Geochemically, SiO₂ (60.47–78.4%) and Al₂O₃ (10.59–17.38%) contents indicate siliceous and aluminosilicate compositions. Factor analysis extracted five components explaining 93.87% of total variance, with Group I (Cu–Pb–Zn–Mn–Fe) accounting for 35.24%, signifying polymetallic sulfide mineralization, while Groups II–III (Pb–As–Rb) contributed 24.74%, representing hydrothermal pathfinder associations. Correlation analysis revealed strong positive relationships among Cu–Cr (0.922), Cu–Zn (0.731), Zn–Pb (0.726), Zn–Cr (0.593), Co–Ni (0.891), and Ni–Cr (0.955), suggesting a common hydrothermal origin. The integrated results indicate structurally controlled mesothermal sulfide and gold mineralization along NE–SW and NW–SE shear zones, highlighting significant base-metal potential within the Nigerian Basement Complex.