Coal mining in the Enugu area of Nigeria has generated a lot of mine waste that has been dumped in landfills and surface dumps chosen for convenience and proximity to the waste source rather than environmental, geologic or engineering considerations. Environmental degradation and groundwater contamination has resulted. Structural analysis of the area shows that the geological formations are fractured with a dominant fracture strike in the E-W direction. These fractures, which are known to influence the flow direction of the rivers in the area, provide significant seepage pathways for contaminant transport. An azimuthal square array resistivity survey confirmed the presence of these fractures in the subsurface as well as their function as seepage pathways. Surface water resources and groundwater exploited from a shallow well has been shown to be contaminated with acidity, iron, and sulphate. The water must, therefore, be treated before consumption by the local inhabitants.

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Coblending of seismic attributes is used in the interpretation of channel geometries in the Rence Field of Niger Delta, Nigeria. We aimed at seismically defining the geometries of hydrocarbon reservoirs with particular emphasis on channels in the shallow marine (offshore) Niger Delta. The coblending application enhanced the ease of detection and the continuity of the channels, leaving the channel environs unchanged. The result of the seismic facies analysis revealed that the Rence Field can be distinguished into two seismic facies, namely, layered complexes and chaotic complexes. The result of well to seismic ties revealed high- and low-amplitude reflection events for sand and shale units, respectively. Seismic structural interpretation of the Rence Field revealed 4 major regional faults and 12 minor faults. Seven of the faults were antithetic, and the rest were synthetic faults. One mega-channel feature that trends east–west was identified in the attribute maps generated. It was characterized by sinuosity of 1.3, with a length of 22,500 m, and a distance of 17,500 m. The average depth of the channel was approximately 170 m with amplitude of 1670 m and the wavelength as high as 7640 m. A depositional model generated from the attribute maps indicated a prograding fluvial environment of deposition. The attribute map also determined that there was shifting in the location of barrier bars within the area. This shifting could be attributed to the growth fault mechanism. At the stoss side of the sinusoidal channel, there were prominent sand point bar sequences. The petrophysical analysis of the well data revealed 90% net-to-gross, 28% porosity, 27% volume of shale, and 24% water saturation indicating that the reservoir was of pay quality. Based on the petrophysical analysis, results, and identification of channel deposits, the study area proved highly promising for hydrocarbon exploration.

Hydrochemical evaluation of parts of Lower Niger Drainage Area was studied. The distribution and concentration of the major ions were assessed. Atomic absorption spectroscopic and spectrophotometric methods were employed in the analyses of chemical species in water, and Piper, Durov and Schoeller diagrams were used in the processing and interpretation of the results. The results of the hydrochemical analysis show the generalized ionic sequence in the study area as