Vertical electrical sounding (VES), employing a Schlumberger electrode configuration, was used to investigate the sediments and aquifer repositories in Itu Local Government Area of Akwa Ibom state, southern Nigeria. This was done in sixteen (16) locations/communities with the maximum current electrode spread ranging between 800-1000m. The field data were interpreted using forward and iterative least square inversion modeling, which gives a resolution with 3-5 geoelectric layers. The observed frequencies in curve types include 31.25% of AKH, 18.8% of AAK and HK and 6.25% of K, QHK, AKH, KA and KHQ, respectively. These sets of curves show a wide range of variabilities in resistivities between and within the layers penetrated by current. The presence of K and H curve types in the study area indicates the alteration of the geomaterials with limited hydrologic significance to the prolific groundwater repository. A correlation of the constrained nearby borehole lithology logs with the VES results shows that the layers were all sandy formations (fine and well sorted sands to gravelly sands or medium to coarse-grained sands as described by nearby lithology logs) with some wide ranges of electrical resistivity values and thicknesses caused by electrostratigraphic inhomogeneity. The geologic topsoil (motley topsoil) is generally porous and permeable and as such the longitudinal conductance (S) values for the covering/protective layer is generally less than unity of Siemens (S < 1Ω −1 ), the value considered for efficient protection of the underlying aquifers by the topmost and overlying layer. The spatial orientations and the leveling patterns of the most economically viable potential groundwater repository within the maximum current electrode separations has been delineated in 2-D and 3-D contoured maps. The estimated depth range for the desired groundwater repository is 32.6-113.1m and its average depth value is 74.30m. The thickness of this layer ranges from 27.9-103m while its average depth has been evaluated to be 63.02m. Also, its resistivity range and average value have been estimated to be 507-5612Ωm and 3365.125Ωm

This paper presents result of 30 vertical electrical soundings carried out in Makurdi, Benue state capital, north-central Nigeria to evaluate aquifer protective capacity and soil corrosivity of overburden units in the study area. This was done using the Schlumberger electrode array to obtain the data and was modelled using computer iteration (Winresist software). The field data gives a resolution with 3-4 geoelectric layers and the observed frequencies in curve types include: 30% of KQ, 16.67% of QH, 6.67% of AA and K, 3.33% of HA, Q and A, 10% of H, KH and HK. Using the longitudinal unit conductance (S), the protective capacities of the study area were classified as 36.67% weak, 10% poor, 40% moderate, and 13.33% as good. The corrosivity ratings of the study area show that 10% is strongly corrosive, 23% moderately corrosive, 37% slightly corrosive, and 30% noncorrosive The results reasonably provide information on areas where industries can be sited and iron pipes can be laid in order to safeguard the hydrological setting for resident's safety in the study area. Regions with moderate/good protective capacity are good sites for locating boreholes. with the disposal of large volumes of waste materials, poses the potential for widely distributed

A geoelectric survey involving vertical electrical sounding (VES) employing Schlumberger electrode configuration was carried out with the aim of evaluating the aquifer potential, electric and hydraulic parameters in Ezza North. Schlumberger electrode configuration was used to acquire data for twelve VES stations. The interpreted and analyzed results reveal four to six geoelectric layers. The VES curves obtained were QQH, QHK, QHA, QQQ, HAK, KHK, HKH and QQ. From the result, the Dar Zarrouk parameters (longitudinal conductance and transverse resistance) were calculated. The longitudinal conductance ranges between 0.1528 and 4.6 mhos. The transverse resistance ranges between 662.4 and 38,808 Xm 2 . The range of hydraulic conductivity is 1.1645-38.0491 m/day, while the range of transmissivity is 89.66-2100.3 m 2 /day from the estimated values. The contour maps were drawn using the electrical and hydraulic parameters, and the distribution of the aquifer parameters is shown. Based on the results, aquifer potential and protective capacity of the study area were determined.

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Seventeen vertical electrical soundings and seven electrical resistivity tomography profiles were carried out at the University of Nigeria, Nsukka, Enugu State, Nigeria. The study involves the use of Schlumberger and Wenner electrodes configuration. The thrust of this work is on determining the vulnerability of the hydrogeological units by employing the aquifer vulnerability index (AVI) method. The resistivity data measured were interpreted manually and with computer software packages, which gave the resistivity, depth and thickness for each layer within the maximum current electrodes separation. The hydraulic conductivity (K) and hydraulic resistance (C) of the protective layers estimated from the primary parameters estimated have values ranging from 0.0434 to 0.4890 m day −1 and 38.37 to 1005.84 day −1 , respectively. AVI of the study shows that the study area is characterised by low to high AVI with moderate AVI as dominant. This is to help in delineating aquifer protective zones and also possible locations, which further helps in groundwater resource exploration and management.