Investigation of iron ore potential in north-central Nigeria, using high-resolution aeromagnetic dataset and remote sensing approach

Abstract

The instability of fuel prices in the international market has adversely affected the economy of Nigeria, which is a developing country that solely relies on crude oil. This has led the country to consider diversifying its economy into mineral resources. The consideration of iron ore as an important mineral for global infrastructure, steel production, and wealth creation has prompted this study to consider its potential within north-central Nigeria. Additionally, no geophysical reports considering the regional distribution of iron ore potential in both the Basement Complex and the sedimentary basins within north-central Nigeria have been previously carried out. This study employs an analytical hierarchy process (AHP) and weighted overlay to integrate the analyses of the high-resolution aeromagnetic data set (HRAMD) and Landsat 8 OLI/TIRS to assess the iron ore potential of the different geological terrain in north-central Nigeria. The ferrous mineral band ratio technique was adopted in processing the Landsat data, and several signal enhancement techniques were performed on the HRAMD, including the first vertical derivative (1VD), analytical signal, center for exploration targeting (CET) grid analysis, Euler deconvolution, and radially averaged power spectrum (RAPS). The shallowest magnetic sources and the high amplitude zones were delineated, and the dominant structural trend of the area was revealed to be WNW-ESE and NE-SW, and both orientations appeared to be favorable for mineralization. The apparent depth estimates of shallow and deep-seated magnetic structures obtained from Euler deconvolution ranged from 127.65 to 3540.64 m, whereas RAPS delineated a range of 285–3710 m. The analytical signal (AS) categorized the magnetism of the area into low, intermediate, and high magnetic zones. The higher magnetic zones were considered to be favorable for mineralization. The ferrous mineral ratio map reveals areas of higher reflectance, which depict zones of iron ore potential. The iron ore potential map was validated using known iron ore mines and deposits, which showed a perfect correlation, and new sites of probable iron ore mineralization within north-central Nigeria were revealed. This article will serve as a guide for stakeholders in the exploration of iron ore deposits.