ASSESSMENT OF DEPTH TO LEAD-ZINC DEPOSIT IN PARTS OF SOUTHERN BENUE TROUGH USING INTEGRATED GEOPHYSICAL METHODS

This study employed the techniques of electrical resistivity, induced polarization and aeromagnetic
methods to investigate and quantify lead-zinc ore deposits. The electrical methods of geophysical
exploration were employed to measure thickness of overburden as well as width of the ore across the
study area. IP method was used to investigate dissemination of lead-zinc sulphides. Aeromagnetic
data over the area was acquired and processed to detect lead-zinc lode as well as magnetic anomalies
present in the study area. This study reveals that there is a lead-zinc lode along the investigation area.
This lode was delineated clearly through the magnetic anomaly signature of an aeromagnetic data
over the area. IP survey results and imaging agrees with the aeromagnetic signature of the lode both
in trend and width. Vertical electrical sounding, Schlumberger array determined the varying
overburden thickness between
20m – 44m across the lode. These techniques have been helpful in
discovering and/or delineating lead – zinc ore deposits but it is suggested that shafting, trenching and
core drilling be used as a comparative study.