Characterization of the Sulfide Deposits in the Southeastern Nigeria Using VLF Method: Insights from Numerical Modeling and Field Examples

D. E. Falebita (Department of Geology, Obafemi Awolowo University, Ile-Ife, Nigeria)
O. Afolabi (Department of Geology, Obafemi Awolowo University, Ile-Ife, Nigeria)
B. O Soyinka (Terracon, Seattle, Washington DC, USA)
A. A. Adepelumi (Department of Geology, Obafemi Awolowo University, Ile-Ife, Nigeria)


A priori geologic and geophysical information has been used to construc conceptual VLF experiments on conductively and inductively coupled overburden geological models of the lead-zinc (Pb-Zn) mineralization zone found in southeastern Nigeria.This is based on the finite element approach to (1) simulate different geologic situations of overburden occurrence, (2) examine the roles played by overburden in modifying and masking VLF responses of a buried conductor target, and (3) confirm the effectiveness of VLF method in mapping lead-zinc lodes found in sedimentary terrains.The computed theoretical model curves and field examples are expected to serve as guide for VLF anomaly pattern recognition due to overburden thickness, resistivity and width of conductor in similar terrain as the study area.


Sulfide;Conductor;VLF;Overburden thickness;Polarization parameters;Nigeria

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