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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

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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.

A resistivity study by vertical electrical sounding (VES) employing the Schlumberger electrode configuration has been used to delineate shallow aquifers in some villages in SouthernUkanafunLocal Government Area of Akwa Ibom State, Southern Nigeria. The information realized from the resistivity data and nearby logged boreholes show that the depths penetrated by currents were all sandy formations with various thicknesses. However, the main aquifers comprise within the maximum current penetration, very coarse – grained (gravelly) sand and fine sand with resistivity in the ranges of 4680-30700 Ωm and 207-2530 Ωm and thickness in the ranges of 43-63 m and 18-40 m respectively. The aquifers with minor hydraulic gradient are separated by thin beds of clay according to lithology logs and these beds were masked in the sounding data due to the principle of suppression.

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The application of geophysical method employing vertical electrical sounding (VES) method in combination with laboratory analysis of aquifer sediments has been used to access the economically accessible groundwater reserve and its protective capacity in some parts of Eastern Obolo Local Government area, the eastern region of the Nigerian Niger Delta. Schlumberger electrode configuration was used to sound twelve VES to occupy the areas that have borehole locations and accessibility for the spread of current electrodes to at least 1000 m. Based on the results, the safe and economic aquifer potential has groundwater reserve of about 168480558±18532861 m3. The desired aquifer thickness and its depth of burial have average value of 52.02 m and 73.14 m, respectively. The area has a fair protective capacity. This is indicated by 58.33% weak, 16.67% moderate, and 25% good protective capacity for the area. This study was done in one of the oil cities, where contaminated Salt River water is used as the major source of water for domestic uses and it is believed that the settlers will appropriate this result and sue for safe groundwater at the indicated depths.

The study area, characterized by prolific surface and groundwater repositories, is faced with the challenges of surface and groundwater pollutions. These pollutions need good management practices to avoid waterborne diseases. In an attempt to solve this problem, the integration of vertical electrical sounding (VES) method with laboratory analysis of borehole water was undertaken to size up the contour of groundwater geohydraulic parameter distributions and their dispositions. These Parameters are fraught with information concerning contaminant plume. Aquifer repositories characterized by fine to coarse sands have resistivity ranging from 166.3-2332.5 Ωm, delineated through the use of manual and electronic processing aided by software packages such as WINRESIST and SURFER. Thickness ranged from 2.6-170.3 m. Using the VES results and water resistivity, porosities were determined using Archie's model. Estimated porosities were employed in the Kozeny-Carman-Bear's Model to estimate the hydraulic conductivity for all the VES stations and good fits were obtained with pump test results. The K values were combined with Dar Zarrouk parameters to infer the hydraulic transmissivity. The results indicate that fractional porosity varies from 0.102 to 0.198. The hydraulic conductivities ranged from 7.48 × 10 −6 to 5.33 × 10 −5 m/s, while the transmissivity values vary between 7.938 × 10 −5 and 3.389 × 10 −3 m 2 /s. The tortuosity of the aquifer also varies from 1.12 to1.35 while the conductance of aquifer per day varies from 259 to 15,575 μS/day. The hydrogeological units are generally prone to interaction with brackish/saline water from the Imo River and corrosion from surface sources due to the high permeability of the layers surrounding the geometries of water repositories. The ranges of parameters estimated are consistent with literatures for studies conducted in other areas with similar geomaterials, therefore indicating the efficacy of the method.