Application of Interpreted Aeromagnetic Data to Decipher Masked Structurally Controlled Pegmatite Mineralization in the Thickly Covered Terrain of Nasarawa State, Nigeria

Abstract

The increasing global demand for lithium, driven by the renewable energy transition and electric mobility, has positioned pegmatite-hosted lithium deposits as strategic mineral resources for the 21st century. The Nasarawa region of North Central Nigeria, situated within the Pan-African reworked mobile belt of the Nigerian Basement Complex, hosts significant pegmatite mineralization with documented rare metal potential. However, exploration efforts in this region face a fundamental challenge: extensive lateritic and sedimentary cover that masks surface expressions of mineralization, rendering conventional prospecting methods ineffective. This study employs an integrated aeromagnetic geophysical approach to detect concealed pegmatite mineralization in the thickly covered terrain of Nasarawa State. High-resolution aeromagnetic data obtained from the Nigerian Geological Survey Agency was processed and analyzed using advanced edge detection techniques including First Vertical Derivative (FVD), Analytical Signal Amplitude (ASA), Tilt Derivative (TDR), and Trend Analysis to identify structural lineaments and magnetic anomalies associated with mineralized zones. The results reveal that areas characterized by moderate magnetic anomalies with distinct horizontal and vertical gradient variations represent potential pegmatite-hosted mineralization zones. Lineaments and intersections of NE-SW trending structures, particularly where fault densities are high alongside magnetic sources at intermediate depths, are identified as possible zones of pegmatite mineralization. The findings demonstrate that integrated aeromagnetic interpretation, combined with structural analysis, provides an effective exploration strategy for identifying concealed pegmatite mineralization in covered terrains. This research contributes to the development of robust geophysical exploration protocols for lithium resources in the Nasarawa pegmatite belt and similar geological settings across Nigeria.