A Further Application of Coefficient of Anisotropy and Reflection Coefficient as Indices in Delineating Groundwater Potential in Basement Complex of Ado Ekiti, Southwestern Nigeria

Abstract

One index might not be enough in geophysical investigation of underground water potentials in basement terrain, there is a need to look into other indices for an improved investigation, the combination of some indices will lead credence to the result hence this work is a further application of coefficient of anisotropy, reflection coefficient and fracture coefficient on spatial distribution of underground water in Ado Ekiti basement complex. This work examined the thickness of aquifer, its resistivity spread and other hydro geological parameters such as total longitudinal conductance, total transverse resistances, coefficient of Anisotropy, reflection coefficient and fracture contract to determine water potentials in the study area. Resistivity and thickness are linearly related for high productive Aquifer formation, thus these indices generated from thickness and resistivity have been examined in other to determine the porosity and permeability and hence transmissivity of the aquiferous zone in the study area. Aquifer resistivity ranges from 7.7Ωm to 545Ωm in weather zone and between 9.5Ωm to 1902.6Ωm in fracture zone these values are within productive range in basement complex environment. Shallow basement of less water potential have been found in part of North west and north east of the study area, total transverse resistance also discovered low porosity at Aiyedun quarters, Elemi housing Estate and Ita Eku these are hard rock zone, this area has also been identified through their coefficient of anisotropy as low or none productive zone the coefficient of anisotropy is higher than 1.5. Area of promising water bearing zone are with the North west, west, south west and south east of the study area.