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The increasing demand for clean water for domestic and industrial purposes for the rapidly growing population of Orlu and its environs motivated this study. Vertical electrical sounding data, employing the Schlumberger array and AB/2 from 1.0 to 350.0 m, was acquired from fifteen respective locations with the aid of ABEM SAS 4000 resistivity meter. The data was processed using IP2WIN 2.0 to obtain layer resistivity curves and generate geo-electric sections. Various aquifer parameters as well as pumping test information from monitoring Wells were also obtained in addition to new model equations for obtaining aquifer transmissivity from transverse resistance and hydraulic conductivity from aquifer resistivity. 2D geospatial maps and 3D models of the aquifer parameters were obtained using Surfer 21.0. Corrosivity and competence of soils as well as aquifer protective capability of this area were also investigated. Results show that aquifer resistivity varies from 554.3 to 23500 Ωm with Orlu having the highest aquifer conductivity and transmissivity and Ntueke recording the least. The highest aquifer thickness and storativity were observed at Nwangele and the least recorded at Ntueke, while the deepest aquifer was observed at Orsu-Ihiteukwa and the shallowest seen at Ntueke. Results also indicated that the soils of most of the locations are essentially non-corrosive and competent, and the aquiferous units are poorly protected from contamination. These findings are central and critical for groundwater development and sustainability as well as structural engineering, agricultural, and industrial activities in this area.

The electrical resistivity method was used to determine the groundwater potential of Ogidi and its environs. Thirteen soundings were carried out at thirteen different locations using the ABEM terrameter (SAS 1000), and adopting the Schlumberger configuration with maximum current electrode spacing of 1000 m. The lithologic logs for the boreholes were used to delineate the geologic sections. The results revealed six to nine geo-electric layers comprising laterite, clayey sandstone, sandstone, water-saturated sandstone and shale. The water-saturated sandstone forms the aquiferous unit. This unit was found to have resistivity values ranging from 363Ωm to 9107Ωm. It is deeply seated in some areas with a depth of 33.2–103 m. It was observed that the hydraulic conductivity varies between 0.001 and 0.066 m/day, while the transmissivity values vary between 0.01 and 4.7 m2/day. Among all the VES points studied, it was observed that VES 1 has the highest transmissivity value and the highest aquifer thickness. In view of the foregoing, it is expected that water will flow more from aquifer in VES 1 since groundwater flow from an aquifer is directly proportional to transmissivity.

Geophysical analysis was carried out to evaluate the challenges encountered in land seismic exploration within the study area. This analysis cuts across various stages in land seismic acquisition. These stages include the following: the availability of the prospect map as originally planned by the prospect owners—the client, the desk study and planning of this map by the seismology section (planning seismologist) for acquisition convenience and the field implementation of the acquisition which the survey, drill and recording (preloading, shooting, swath move, line check, LAUX crew and recording platform) sections carried out. The challenges observed included environmental challenges, noise interference, weather conditions (statics or electrostatics interference), line break, faulty equipment, wrong detailing, cake or expired explosives, poor or compromised supervision, security and permit challenges. These challenges are peculiar to Nigeria due to inadequate implementation of policies that guide human settlements and activities. Nigeria is within the climate region where most at times it is very impossible to control natural events like cloudy weather, rainfall, thundering and lightening. As such, the problem of static charges interfering with acquired seismic data becomes inevitable, mostly during the rainy season. Almost total dependency on imported technology and lack of readily available experienced manpower also contribute to these challenges, most especially when it has to do with proper inspection of equipment and materials required for the acquisition and supervision processes. Approaches to follow to minimize the observed challenges were equally highlighted.