Geophysical and Geochemical Investigation of Gold Mineralisation in the Schist Belt of Kaduna State, North West Nigeria

The schist belts of North West Nigeria contain documented gold mineralisation in quartz veins and shear zones associated with Pan-African terrane assembly, and recent artisanal gold rushes in Kaduna State have confirmed the existence of economically significant concentrations that warrant systematic exploration combining geophysical and geochemical methods. This study integrates induced polarisation, magnetic profiling, and multi-element soil geochemistry to characterise gold-hosting structures in a 40-square-kilometre study area in the Birnin-Gwari schist belt. Dipole-dipole induced polarisation and resistivity surveys were conducted along 14 parallel profiles at 100-metre spacing, acquiring both apparent chargeability and resistivity data. Ground magnetic surveys were conducted simultaneously along the same profiles. Soil geochemical samples at 50 by 50 metre grid spacing over anomalous zones were analysed by aqua regia digestion and ICP-MS for a 52-element suite. High chargeability zones (greater than 20 milliseconds) consistently correspond to low-resistivity corridors trending NE-SW, interpreted as sulphide-bearing shear zones hosting disseminated pyrite and arsenopyrite. Gold concentrations in soil samples up to 280 parts per billion are spatially associated with the IP-defined shear corridors and with positive magnetic gradient lineaments interpreted as mafic dykes providing favourable chemical and structural traps. Three drill-ready targets are defined by the three-dataset coincidence criterion, with the highest-priority target showing 450 metres of strike length of the chargeability anomaly exceeding 30 milliseconds. Keywords: gold mineralisation, induced polarisation, schist belt, Kaduna State, geochemistry