Geoelectrical And Geochemical Insights Into Exploration Potentials Of Kaolinitic Clay Deposits In Obudu Massif, South Eastern Nigeria

Abstract

Combining various techniques in delineating mineral deposits increases the chance of practical discovery and characterization of potential mineralization zones. Choosing a suitable dataset is a key factor for a detailed geophysical and geochemical mineralization mapping. geophysical and geochemical techniques have proven their effectiveness as tools for reliable mineral mapping. In this study, twenty (20) Vertical Electrical Sounding (VES) stations were observed with maximum AB/2 of 300m and 5 transects electrical resistivity tomography traverses were conducted along selected profiles. The geoelectrical results revealed four to six electro-lithostratigraphic units.  The electro-lithostratigraphic unit with resistivity varying between 10 Ωm and 90 Ωm were identified as kaolinite-rich zones. Samples of kaolinite collected were subjected to laboratory analyses ensuring their compliance with industrial standards. X-ray Diffraction (XRD) confirmed the presence of kaolinite as the dominant mineral, along with trace amounts of quartz and feldspar. X-ray fluorescence (XRF) revealed high concentrations of aluminum (Al₂O₃) 73. 5% and silicon (SiO₂) 25.6% respectively. The low content of iron oxide (Fe₂O₃) 0,8% and titanium dioxide (TiO₂) 0.1% observed established the purity of the kaolinite. Scanning Electron Microscope (SEM) revealed well-formed kaolinite crystals with hexagonal platelets while the particle size distribution with the majority of particles being <2µm. The specific gravity (SG) test revealed an average 2.92kg on average and further support the high-quality index of the deposit. The findings revealed that the kaolinite deposits in Obudu Massif, Southeastern Nigeria possess the requisite quality and quantity for commercial exploitation. The geoelectrical resistivity method proved to be an effective tool for mapping and evaluating the deposits, offering a cost-efficient approach for preliminary exploration. This study provides a framework for future geoelectrical assessments of mineral deposits and underscores the potential economic benefits of developing kaolinite resources in the region.