Evaluation of Clay Mineral Deposits in Ohiya, Southeast Nigeria Using the Self Potential Method and Lithologs
D. E. Azunna
Department of Physics (Geophysics), Michael Okpara University of Agriculture, Umudike, P.M.B. 7627, Umuahia, Abia State, Nigeria.
G. U. Chukwu
Department of Physics (Geophysics), Michael Okpara University of Agriculture, Umudike, P.M.B. 7627, Umuahia, Abia State, Nigeria.
E. U. Nwokoma *
Department of Physics (Geophysics), Michael Okpara University of Agriculture, Umudike, P.M.B. 7627, Umuahia, Abia State, Nigeria.
A. Akenami
Nigerian Geological Survey Agency, Owerri, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
A self potential survey was carried out on the study area. Four prospects were considered. The prospects investigated had a total area of 2.34 km2. 18 profiles were obtained from the prospects alongside three other random considered profiles. A total of 315 SP measurements were obtained using the direct potential method with a 10 m increase in the electrode spacing along each of the profiles. Obtained data show a potential range of -2 mV to -600 mV and 1 mv to 251 mV. On analysis, SP spectral signatures and the tomography map reveals that there were also non-conductive materials like silt, sandstone, sand, etc. which constitutes impurities and the overburden. The Iso-Potential contour map of the study area also reveals Nkwoebo, Egbeada and Umuoram as areas of likely kaolin abundance. Litho-logs of excavated sites were obtained to give us a quantitative clue of the mineral in the investigated prospects. It was observed that the overburden thickness is about 1.22 m, the thickness of kaolin deposit to be above 12.2 m and the average bulk reserve is about 74,360,000 metric tons.
Keywords: Kaolin, self, potential