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In this study, effort has been made to achieve a comprehensive geophysical investigation on immediate and remote causes of structural/foundation failures, specifically highway(s) within the southwestern basement complex region of Nigeria. Geophysical survey involves the use of Very Low Frequency Electromagnetic method (VLF-EM) which was complemented with electrical resistivity method using two techniques; 2D Electrical Resistivity Tomography (ERT) and Vertical Electrical Sounding (VES) along Akure/Oba-Ile Airport Road, which covers a pilot test of 600 m. The VLF-EM survey produced EM anomalies and identified possible linear features along the study area. The results obtained from the VES were used to determine the second order parameters for determination of subsurface integrity/competence. The geoelectric sections identified three to five geoelectric/geologic subsurface layers along the traverse. The ERT gave information on the subsurface characteristics whose section delineated five major geologic layers comprising of the topsoil, weathered basement, fractured zone, partly fractured basement and the fresh basement. This shows that fracture and weathering are responsible for the structural failures along the study area which are products of probability functions of geodynamics. The methodology can be adopted as a model to proficiently and quickly detect changes in subsurface resistivity, integrity and identify anomalous zones which can serve as useful tool in the understanding of the probability functions of geodynamics that can bring structural and foundation failures within the basement complex region.

Wireline signatures were used to identify hydrocarbon bearing sands and evaluate Petrophysical parameters for hydrocarbon pore volume determination. Well to seismic tie revealed that these reservoirs tied direct hydrocarbon indicators –bright and dim spots –on the seismic sections. Three hydrocarbon reservoir were delineated. Estimation of the volume of hydrocarbon in place revealed that reservoir A contained 1675091.54 ± 102 feet of gas in place, while reservoir B contained 163661.83 barrels ± 80 barrels and reservoir C contained 1739170.41 ± 102 cubic feet of gas

This research evaluates the significance of geotechnical and Electrical Resistivity methods in studying structural integrity as fundamental factors that may account for failure in a typical sedimentary environment of Ukpenu Primary School, Ekpoma, Edo State, Nigeria. Two methods were used in this study such as the Electrical Resistivity approach involving the use of Lateral Horizontal Profiling (LHP), 2D Electrical Resistivity Tomography (ERT), and Vertical Electrical Sounding (VES) techniques. While geotechnical method involved the collection of soil samples from the study locations for the characterization of the soil properties that are very vital to foundation studies. Nine VES were carried out using Schlumberger array with current electrode spacing varying from 1 to 40 m, with 2-D ERT using Dipole-Dipole electrode array with inter-station separation of 5 m and an expansion factor varied from 1 to 5 while LHP involve Wenner array with an electrode spacing of 5 m interval and was used to determine the vulnerability factors for the building sustainability. The VES interpretation results were used to determine the second-order parameters for the determination of vulnerability. The results obtained from the two methods review that both are very fundamental to foundation dynamics. However, electrical attributes were found to give better information in terms of depth, lateral extent, layer stratification, and nature of materials which make it an indispensable tool over geotechnical attributes whose depth of investigation is up to a maximum of 5 m which poses great limitation in the evaluation of structural integrity, against stress, and strain occasion by geodynamic activities that often result into fracture, crack, highly weathered formation that usually goes beyond the shallow depth of investigation. Therefore, it can be stated that resistivity attributes account for 90% of the major contributing factors that affect foundation vulnerability.