Geophysical Survey for Mineral Exploration in Zamfara State Using Magnetic Methods

Zamfara State in the North West geopolitical zone of Nigeria is underlain predominantly by Precambrian basement rocks hosting diverse metallic mineral occurrences, including gold, iron ore, and tantalite that have attracted artisanal mining activity. This study applies ground magnetic surveying to characterise subsurface geological structures and identify anomalous zones with mineral exploration potential in a selected area of Zamfara State. A proton precession magnetometer was deployed along a grid of profiles to measure the total magnetic field intensity at stations spaced fifty metres apart. Raw magnetic data were corrected for diurnal variation and the international geomagnetic reference field before applying upward continuation and reduction-to-pole filters. Horizontal gradient and analytic signal maps were derived to delineate source body edges and estimate depths to magnetic bodies. Interpreted anomalies are correlated with surface geology to distinguish lithological contacts, intrusive bodies, and fault-related structures that may control mineralisation. The study integrates reconnaissance rock sampling results to test the association between magnetic highs and identified mineralised zones. Outcomes are expected to assist the Zamfara State Government and licensed exploration companies in prioritising drilling targets and reducing exploration risk. This research introduces undergraduate students to the practical application of potential field methods in mineral exploration within a Northwest Nigerian context. Keywords: magnetic survey, mineral exploration, Zamfara State, basement complex, aeromagnetics.