Application of Aeromagnetic Data to Delineate the Mineralization Zones within Shanga (Sheet 96) Northwest Nigeria

Abstract

The goal of the present study is to identify and delineate the mineralization zones and depths of prospective mineral occurrences in Shanga (sheet 96), parts of the northwest Nigerian basement complex, by analyzing aeromagnetic data. This was accomplished by reducing the residual magnetic intensity (RMI) data for the research area to the equator (RTE), which was followed by the application of two source edge detection/interpretation techniques; first and second vertical derivatives (FVD and SVD), while the analytic signal (AS), was applied to the TMI data. The AS approach of depth estimation was also applied to the Shanga RMI data to establish the minimum depth at which the minerals are likely to occur. Using FVD map, structures that may be responsible for mineralization within the study area were identified and confirmed to eastern basement portion of the study area. The primary structural trend in the region is ENE-WSW, followed by NE-SW, WNW-ESE, NW-SE, and NNE-SSW. The high analytic signal within the schist has been attributed to intrusions and solidification of mineralization fluids with structural linkages, allowing the area's mineralization zones to be identified. The analytic signal map showed amplitudes ranging from 0.001 nT/m to 0.421 nT/m. Additionally, the SVD map showed mineralization boundaries that matched the AS map's mineralization zones. The analytic signal depth method revealed a minimum depth of occurrence for the minerals ranging from 0 to 11.457 m, and the mineralization zones delineated have one or more structural lineaments passing through them, confirming that they are responsible for mineralization fluid passage and mineralization hosting within the study area.