Geophysical Investigation of Lead-Zinc Mineralization Targets in the Southern Benue Trough, Ebonyi State

The southern Benue Trough in Ebonyi State is recognized as a major lead-zinc mineralization province, yet detailed geophysical characterization of deposit geometry and structural controls remains limited. This study applies combined induced polarization and self-potential surveys to identify mineralization targets and constrain the structural architecture of lead-zinc deposits in selected areas of Ebonyi State. Fourteen dipole-dipole induced polarization profiles were established over known and inferred mineralization zones, with current electrode separations of 20 m and 40 m. Chargeability and resistivity pseudosections were generated and jointly inverted to produce two-dimensional subsurface models. Self-potential measurements were collected along the same profiles to detect electrochemical anomalies associated with sulphide ore bodies. Chargeability highs exceeding 18 ms collocated with low resistivity zones (less than 20 ohm-m) define conductive ore zones consistent with disseminated galena and sphalerite mineralization. Positive self-potential anomalies of up to 95 mV mark the redox interfaces above sulphide concentrations, providing direct evidence of active geochemical processes related to ore occurrence. Three major mineralization targets are outlined on the basis of the integrated geophysical response, with estimated depths to the tops of anomalous bodies ranging from 10 m to 45 m. The results indicate that mineralization is structurally controlled by northeast-trending faults consistent with regional tectonic patterns. These findings serve as a guide for follow-up exploration drilling and contribute to the broader mineral resource inventory of Ebonyi State.

Keywords: induced polarization, self-potential, lead-zinc mineralization, Benue Trough, sulphide ore