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The increasing prevalence of water-borne diseases necessitates periodic monitoring of domestic and drinking water sources. The current study assessed the safety of well water in the four emirate zones (Gwandu, Yauri, Argungu, and Zuru) of Kebbi State, Nigeria. Using normal procedures, samples of well water were examined for heavy metals, physicochemical characteristics, and microorganisms, and the results were compared to the World Health Organization (WHO) drinking water criteria. The heavy metals' chronic daily ingestion (CDI) and hazard quotient (HQ) were also determined. The results showed that well water in the four emirate zones had normal temperature, biochemical oxygen demand (BOD), dissolved oxygen (DO), total suspended solids (TSS), and zinc (Zn). However, non-permissible concentrations of lead (Pb), iron (Fe), cadmium (Cd), chromium (Cr), and pH (Gwandu and Argungu only) were detected in all the water samples. Except for Cd and Cr in children, the CDI and HQ of the heavy metals were normal. The microbiological examinations revealed that the water samples from the four zones had abnormal levels of Bacillus species (bacteria), Escherichia coli (bacteria), Staphylococcus aureus (bacteria), Aspergillus niger (fungi), Mucor racemosa (fungi), and Paecilomyces variotti (fungi). The results obtained suggest that well water in the four zones is not suitable for human consumption unless treated.

Three wells A1, A2 and A3 were identified on the 'T-X' field in onshore Niger Delta. A comprehensive petrophysical analysis on one of the wells (well A1) was carried out in order to come up with physical properties such as shale volume, porosity (Φ), permeability (K), fluid saturation, and net pay thickness, among others for future development planned of the oil field. A well log data from this field have been examined and analyzed. The logs include gamma ray (used for the identification of lithology), resistivity and porosity logs (used for delineating hydrocarbon bearing reservoirs). Wireline log analysis was employed in the characterization of the reservoirs in the well studied; the hydrocarbon sands were delineated by the use of gamma ray, resistivity and density/neutron from which the reservoir quality were determined. Fluid types defined in the reservoirs on the basis of neutron/density log signatures were basically water, oil and gas.Eighteen (18) reservoirs (AR1 to AR18) were identified, among which twelve (12) are hydrocarbon-bearing reservoirs. Permeability and porosity values range between 1-6206md and 6-28% respectively. Water saturation recorded between 15-100% in the identified reservoirs which indicated that the proportion of void spaces occupied by water varied from low to high values, thus, indicating both low and high hydrocarbon saturation. Plot of hydrocarbon saturation and porosity showed a linear trend and strong linear relationships between permeability and porosity was also observed in all the reservoirs identified indicating that they are permeable and have pores that are strongly interconnected. This study has really demonstrated that petrophysics has a vital role to play in reservoirs characterization.

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High-resolution aeromagnetic data of parts of Middle Benue Trough, Nigeria (sheets 212, 213, 233 and 234) was interpreted by applying source Parameter Imaging (SPI) and Spectral Depth analysis with the aim of mapping out the magnetic lineaments and analysing magnetic signals coming from different sources. The results from the derivatives maps show major and minor lineaments trends in the NE-SW and NW-SE directions respectively. Results from SPI show the maximum sedimentary thickness of about −4546.7 m (−4.5467 km) around the region of Awe, Aman, Langtang south, Gassol and the north-eastern part of Donga. Minimum depth of −167.9 m (−0.1679 km) around the region of north of Shendam, north of Wase, north-eastern part of Aman, Bantaji, Donga, Ibi and Bali. The residual map was divided into twenty-five sections. Spectral Depth was run for each of these twenty-five sections, the result shows that the depth to the deep magnetic source ranges between −0.65 km and −3.35 km. The depth to the shallow magnetic sources ranges between −0.03 km and −0.44 km showing the presence of magnetic intrusive bodies within the sediments. Since the sedimentary thickness of 3.0 km and above is only sufficient for hydrocarbon maturation and accumulation, then the results from this present study show that the study area might be sufficient enough for hydrocarbon maturation and accumulation.