An integration of remote sensing, geographical information system (GIS) and 2D resistivity techniques was used to evaluate the groundwater potential of Obafemi Owode local government area (LGA) in Ogun State, southwestern Nigeria. A composite Landsat 7 image was used to produce land use and lineament of the study area. Advanced space-borne thermal emission and reflection radiometer (ASTER) data were used to generate slope and drainage density. The study adopted modified drastic model for groundwater potential, integrating six parameters which are land use, lineament density, slope, drainage density, geology and soil map. The contribution of each theme to groundwater potential was weighted and ranked using ArcGIS 10.2 software. The groundwater potential zone of the study area delineated five distinct zones which include very high (196.39 km 2), high (334.64 km 2), moderate (481.76 km 2), low (298.46 km 2) and very low (95.73 km 2). Eight zones were delineated for further study. A total of 4.8 line km of 2D resistivity profiles were investigated in one of the designated zones labeled "area D" based on the groundwater potential map. Pole-dipole and dipole-dipole arrays used reveal five geoelectric layers within the study area. The 2D inverse models of resistivity variation with depth suggest the occurrence of potential carbonate and silicate aquifers. To verify the interpreted results within the "high" groundwater potential zone, a well was drilled on traverse 1. A potential water-bearing aquifer was encountered at a depth of 75 m. The groundwater potential map of the study area was tested with five existing wells, and the result was impressive. The outcomes from this study show that the high potential zones would play a key role in future expansion of drinking water and irrigation development in the study area.

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Hydrogeophysical studies have been undertaken at Irepodun/Ifelodun local government area of Ekiti State, Nigeria. The area is underlain by the Basement Complex rocks. The study involved very low frequency electromagnetic (VLF-EM) and electrical resistivity methods. The results are presented as profiles, sections, curves, charts and maps. VLF-EM anomalies were evaluated using geoelectric soundings. Geoelectric sounding results enabled the determination of overburden thickness, transverse unit resistance, longitudinal unit conductance and coefficient of anisotropy (). Overburden thickness zones of 45 to 55 m were classified as high, 15 to 45 m as moderate and values less than 15 m as low. Afao, Obo, Iyin, Araromi, Iketun and Igede are of moderate to high groundwater potential, while other towns are of low groundwater potential. Longitudinal unit conductance showed that the area is characterized by sequence of good, moderate and weak groundwater protective capacities. Computed λ values revealed that the northern flank (Esure and Iropora) are underlain by charnockite of low λ (1.0-1.1) with other areas of high λ (1.1-2.1) underlain by granite and migmatite gneiss. Groundwater development is feasible in Araromi, Afao, Iyin, Obo, Iketun and Igede but marginally feasible in the other towns. Thus, groundwater potential of Irepodun/Ifelodun local government area is generally low.