Geoelectrical resistivity sounding surveys was carried out at two locations (A and B) in the new CanaanCity residential estate of Canaan land Ota, Ogun state in order to locate possible targets for groundwater explorations. A total of twelve (12) vertical electrical soundings were conducted using the Schlumberger array configuration. The interpretations of the VES curves revealed five to six geoelectrical layers at location A which comprises VES1-7. The geoelectric units consist of the topsoil, sandy clay, lateritic clay, confining bed (clayey sand), and main aquifer (sand). The top of the aquifer in this part of the study area is between 40 m and 83.5 m. Likewise, a total of five to seven layers of geoelectrical units were delineated at the location B portion of the study site (VES 8-12) similar to location A with an addition of the shale unit that was interpreted to be that of the Akimbo Formation of the Dahomey Basin. The depth to the top of the productive aquifer within location B is in the range of 40-112.4 m. The delineated basal shale layer is impermeable, serving as the base seal rock for the confined aquifer system. The estimated porosity values range from 28% to 74%, indicating that the highly porous aquifer system in the area is the coastal plain sands mixed with the alluvium sand of the Benin Formation of Dahomey Basin. The study revealed the complexity of the productive aquifer system in the area and its undulating topography.

Investigation into understanding the genesis of brines in southeast Nigeria was carried out utilizing high-resolution potential field (HRPF) data. This study reveals that igneous intrusions and associated hydrothermal fluids are responsible for brine generation. The obtained result of the analytic signal revealed the locations and spatial distribution of short- and long-wavelength geologic structures associated with igneous intrusions. The low pass filtering, upward continuation, and 2D modelling procedures showed key synclinal structures which coincided well with the location of brine fields. The results showed that salt ponds are common in the neighborhood of igneous intrusions. To validate this finding, a conceptual model describing igneous-related hydrothermal circulation systems that are driven by convective cells of the hydrothermal fluid and overburden loads was generated. This model fits reasonably well into the overall stratigraphic and geologic framework of the study area.

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