This research compared the interpretation results of the Vertical Electrical Sounding data acquired using the conventional Schlumberger and modified Schlumberger arrays with a view to assessing the effectiveness of the modified Schlumberger arrays of vertical electrical sounding as an alternative to the conventional Schlumberger array at sites with space constraint during groundwater exploration. A total of thirty-seven (37) sounding locations were occupied and one hundred (100) sounding data for both conventional Schlumberger and modified Schlumberger arrays were collected across different rock units within Ibadan metropolis, south-western Nigeria, with electrode spacing (AB/2) ranging from 1 to 75 m. The field data were interpreted qualitatively by curve matching and computer iterative methods. Also, statistical analysis of subsurface units and the coefficient of correlation “R” of the statistical plots of the field data shows the relationship between the different arrays. The raw data plot of the different arrays shows significant similarities while statistical analysis of the geo-electric parameters obtained from the different arrays across varied lithologic units show that strong relationships exist between the different field methods. The coefficient of correlationRwith values ranging from 0.7 to 0.99 implies that a good similarity exists between the different field methods employed in this study. Hence, modified Schlumberger arrays can be said to be a good alternative to the conventional Schlumberger array for groundwater exploration especially in urban settings where space constraint is a major challenge.

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The integration of Ground Penetration Radar (GPR), magnetic and electrical resistivity methods revealed detailed and cost effective identification of zones of potential archaeological interest at the theatre of war in Igbajo. The Ground Penetrating Radar (GPR) were acquired using the GSSI SIR 3000, the magnetic method were acquired using the proton precession magnetometer while Ohmega resistivity was used to acquire the electrical resistivity data. The applications of geophysical method to delineate the depth and locations of archaeological materials have been demonstrated. The result of the magnetic survey showed regions of high magnetic intensity which indicates the existence of certain buried artifacts; this assisted in the gridding of the Ground Penetrating Radar (GPR) profiles. Significant features were observed on the radargram which correlates with high resistivity anomalies observed on the inversion profile. It was observed that a region of high resistivity values on the inversion coincides with the ground penetrating radar on the radargram. The results show that the region with the highest resistivity between 510-54959 Ohm-m and at depths between 0.5-3 m from the resistivity inversion indicates the possible presence of artifacts which can further be confirmed through excavation

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