Volume 1, Issue 2, July - December, 2024

Integrated geophysical methods for gold exploration in artisanal mining site of Iperindo, Southwestern Nigeria

Kazeem O Olomo1^1♦, Oluwatoyin K Olomob²

¹Department of Earth Sciences, Adekunle Ajasin University, Akungba-Akoko, Ondo State, Nigeria
²Department of Geosciences, Confluence University of Science and Technology, Osara, Kogi State, Nigeria

^♦Corresponding Author
Department of Earth Sciences, Adekunle Ajasin University, Akungba-Akoko, Ondo State Nigeria

ABSTRACT

Combined Geophysical surveys involving ground magnetic, Very Low Frequency Electromagnetic (VLF-EM), Vertical Electrical Sounding (VES) and Horizontal Profiling (HP) (VES&HP), and Induced Polarization (IP) were carried out at the gold mining site of Iperindo, Southwestern Nigeria. This is aimed at delineating geologic structure and its relation to mode of mineral occurrence and depth to mineralised body. This demonstrates the reliability and effectiveness of combined geophysical surveys in mineral exploration. Interpreted profiles of ground magnetic data revealed fractures, veins, and lithological contact in the study area. Depth estimation of delineated geological structure using Peter’s half slope method shows the depth vary between 50 m and 500 m. VLF-EM results revealed shallow linear geological features occurring at depth range of 40 - 200 m. The linear features approximately trend NE-SW, W-E, and NW-SE directions. Interpretation of VES/HP and IP results showed variations in resistivity and chargeability values, respectively. Delineated geologic structures from VES/HP interpreted 2-D section correspond to zone of high chargeability from IP interpreted 2-D section. This indicates the presence of disseminated mineral deposits within the geological features. This study revealed that the occurrence of gold within the mining pits is structurally controlled and disseminated. The study has provided the effectiveness of geophysical application in mineral exploration and the methodology can be applied in any similar geological terrain to unravel mineralization potential.

Keywords: Chargeability, disseminated mineral, geologic structure, quartz vein

Discovery Nature, 2024, 1(2), e5dn1023

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DOI: https://doi.org/10.54905/disssi.v1i2.e5dn1023

Published: 27 August 2024