Assessment of the Economic Significance of Gold: A Reappraisal of the Ilesha Schist Belt, Southwestern Nigeria

Ahmed K. Usman; Mahmood Umar; Bala Balarabe; Yusuf A. Hassan; Aliyu Muhammad; Saidat O. Abdulrasheed

doi:10.47814/ijssrr.v8i5.2714

Ahmed K. Usman Physics Department, Ahmadu Bello University, Zaria, Nigeria/Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
Mahmood Umar Physics Department, Ahmadu Bello University, Zaria, Nigeria
Bala Balarabe Physics Department, Ahmadu Bello University, Zaria, Nigeria
Yusuf A. Hassan Physics Department, Ahmadu Bello University, Zaria, Nigeria
Aliyu Muhammad Physics Department, Ahmadu Bello University, Zaria, Nigeria
Saidat O. Abdulrasheed Pan African University, PAUWES, Algeria

DOI: https://doi.org/10.47814/ijssrr.v8i5.2714

Keywords: Gold Mineralization; Low Resistivity / High Conductivity Zones; Pegmatitic Veins; Threshold; Iperindo

Abstract

Nigeria, endowed with significant gold deposits, holds substantial economic potential, particularly in the northwest and southwest regions within the Schist Belts. In the Iperindo axis of the Ilesha Schist Belt, artisanal mining has been reported; however, the lack of comprehensive geoscience data hinders optimal resource development. This study evaluates the economic viability of gold occurrences in the area, leveraging geoscience research findings. To assess gold mineralization potential, Geonics EM34-3 and SuperSting R8/IP/SP meters were used for frequency domain electromagnetic (FDEM) and electrical resistivity tomography (ERT) profiling, alongside geochemical sampling of soil and stream sediments. Apparent resistivity data from ERT profiles were inverted using RES2DINV software, while Oasis Montaj was utilized to generate 2D conductivity/resistivity sections, maps, and 3D subsurface models. The results suggest the presence of gold or base metals in pegmatitic veins within low-resistivity, high-conductivity zones. Additionally, processed geochemical data identified areas with substantial mineralization potential. These findings underscore the economic potential for commercial gold exploitation in the Ilesha Schist Belt. Instead of further expanding artisanal mining, structured commercial development could enable the government to collect royalty taxes, create employment opportunities, and foster economic growth for both the local community and the nation.

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