P-wave and S-wave velocities were obtained from seismic refraction survey in the foundation layer of Eket, the study area. The Tezcan's approach discussed extensively in the work was used in conjunction with the existing mathematical relations between elastic parameters and seismic refraction velocities for the study of foundation layers in the study area. Based on the results, the elastic constants, allowable bearing pressure/capacity, ultimate bearing capacity and other parameters in Table 1 were determined. The result shows that allowable bearing pressure increases with increase in shear modulus and shear wave velocity. The empirical relation between allowable bearing capacity and shear modulus shows that the allowable bearing capacity increases with depth. Comparing our findings with some ranges of safe allowable bearing capacities of similar non cohesive/granular soils in literatures, the second layer with allowable bearing capacity range of 72.56-206.63 kN•m −2 (average = 154.78 kN•m −2) has been considered to be the safe shallow engineering foundation in the study area. The empirical relations between allowable bearing capacities shear modulus and shear wave velocity, in conjunction with the inferred maps, which serve as our findings, will be used as guide in the location of foundations. The inferred ultimate and allowable capacities correlate maximally for the two shallow foundations penetrated by the seismic waves. This perfect correlation reflects the uniqueness of the method.

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1D resistivity sounding survey was combined with geological and geohydrochemical information in order to examine the aquifer vulnerability. Ten Schlumberger soundings were executed along one profile on the basis of proximity to functional boreholes. Ten samples of groundwater from nearby boreholes were checked for concentrations of significant trace element in the laboratory. The resistivity and geohydrochemical information were employed to examine the level of protection and the associated possible risk of the groundwater repository in the mapped area. The interpreted overburden parameters (resistivities and thicknesses) of water repositories were deployed to determine the integrated electrical conductivities (IEC) and susceptibility of hydrogeological units to surface contaminations. Based on results, Eket and Onna on the southern part of Nsit Ubium have IEC which reflect medium to poor protection capacity based on slightly protected and vulnerable protective layers above the underlain groundwater within the approximate depth range of 15-30 m. Nsit Ubium, the northern zone of the survey area, has a wide range of resistivity which creates windows or vulnerable pathways for percolation of waste pollutants from the surface which flow at the deeper layer. However, layers within 15-25 m depth provide good protection to their underlying aquifer based on IEC which are >1  -1 . Hydrochemical parameters also show higher values that are beyond the 2006 World Health Organization (WHO) standards. The integration of resistivity data and the hydrochemical data showed that the dominant topmost cover layers of the study areas are grossly vulnerable due to drainable pores in the formation.

We considered the constants obtained for tau (𝜏)Field in the Niger Delta basin from well-log data of three wells (A,B,C) to investigate the effect of inclusion of these constants on density-velocity relation using Hampson Russell Software to generate density curve in tau field. The curves were compared to those generated from Gardner and Lindseth constants and in-situ density curves. Many researchers have worked on constants for density-velocity equations for different Fields; their results always differ from Gardner and Lindseth constants including the constants of Atat et al., 2020 which are considered in this investigation as Tau Field local fit constants. Our findings support the results of these researchers. Results indicate over estimation of density curves when using Gardner and Lindseth constants. The challenge is that in-situ density curves are not accurate due to sand-shale overlap of density values. The most improved and accurate result is given by the density curves obtained using the constants for specific sand and shale lithologies (local fits). This verifies the need for the determination of constants for local fit of the oil field under investigation. The pink curves truly indicate the density estimation for the tau field which is very reliable in the characterisation of reservoir.

Petrographic and provenance studies of heavy minerals in Ifelodun sediment were carried out. Sediment samples from eight locations were obtained from the study area; sieved to allow only sand-size lithology. The result was achieved after subjecting this sieved lithology obtained to analyses using a binocular (transmitted and reflected light) microscope. Minerals were separated in a funnel using bromoform with a specific gravity of about 2.89 (gravity method). The heavy minerals present in lithologic sand units are mainly staurolite, tourmaline, zircon and other opaque minerals including cassiterite. The most dominant non-opaque mineral is staurolite with 27.5% of the total minerals counted in the area. Staurolite is very appreciable in locations AR1 with 60% presence (which is 80% of the non-opaque minerals), AR3, AR5, AR7 and OL15b (each with 30%). OL15b also recorded a better amount of tourmaline (20%); Zircon is better in OL6b with 20% of the heavy minerals available in this location. The source rock predicted is porphyroblastic schists.