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Groundwater is a vital natural resource that plays a significant function in sustainability of living things on earth. Its exploration requires special skill for optimum exploitation. Shuttle Radar Topography Mission (SRTM)and Vertical Electrical Sounding (VES) were used to detectthe stratigraphy and subsurface structures controlling the groundwater system around Iju -Ota, Ogun State, Southwestern Nigeria. Nineteen (19) VES points were carried out where there were dense concentrations of lineaments and interconnected to establish the connection of the observed lineaments with groundwater occurrence in the study area using Schlumberger array, with electrode spacing of AB/2 varying from 180 to 320 m. The analysis of SRTM data revealedthe dominating structural NE-SW and NW-SE trends, which control aquifer structure. The geoelectrical parameters from the VES results were used to map the stratigraphic sequences in the study area. Six (6) units that comprisethe topsoil, lateritic clay, clayey sand, mudstone, sand (main aquifer), and shale or clay were identified in the study area. The aquiferous unit around Iju -Ota axis ranged from 30 to 80 m. Theextracted from the hill shaded SRTM data and the result of VES revealed that the thickness of the aquifer is as a result of interconnectivity of the lineaments observed in the SRTM data suggesting that the groundwater occurrence in the study area is chiefly controlled by these fractures.

The study of aquifer problems in Gosa area of Abuja, North-central Nigeria, has been undertaken. Abuja, the capital city of Nigeria, is underlain by Precambrian basement rocks. Vertical electrical sounding (VES) was carried out at twelve locations within and around the Gosa area. The interpretation of the data obtained from the sounding revealed that six non-aquiferous geoelectrical layers overlie the unfractured basement. The first layer with average thickness of about 0.5 m and resistivity of 83 Ohmm. The thickness of the second layer is about 0.7 m and resistivity of 438 Ohm-m. The third layer is about 3.4 m thick and resistivity of about 63 Ohm-m. The fourth layer with average thickness of about 16.0 m and resistivity, 236 Ohm-m. The fifth layer with average thickness of 42.7 m and resistivity of about 68 Ohm-m. The thickness of sixth layer varies from 42.7 m to infinity and resistivity of about 2067 Ohm-m. Eight boreholes of varying depths, 45 to 70 m were drilled. Other areas were drilled with good yield of static water level of about 3.7 m, whereas Gosa aquifers were found dried. It could be attributed to basaltic intrusion that shattered the aquifer bearing rocks thereby devoid water in the zone after pronouncing from geophysical investigation.

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