Petrophysical imaging of two reservoirs of Amangi hydrocarbon field of the Niger Delta of

No abstract

No abstract

This research investigates the effect of landfill leachate on the groundwater in “Odum”, a community that plays host to a dumpsite along  Choba/Alakahia road in Obio/Akpor Local Government Area (L.G.A.) of Rivers State, Nigeria. Five vertical electrical soundings (VES) were conducted using the Schlumberger configuration and also five horizontal profiling were done using the Wenner configuration. The field data were acquired using ABEM tarrameter SAS 300C, and processed using the IP TWO WAY software. The results showed that the area is composed of sandstone, clay, laterite, sandy clay, and sand. Also, from careful analysis and interpretation of the processed data it was observed that contaminated zones have low resistivity (high conductivity). Strikingly, areas of low resistivity such as 11.9 Ωm and others with high resistivity up to greater than 1818 Ωm do exist. The results show that groundwater around this landfill contaminated area contains highly conductive leachates like sulphur, methane, ammonia gas at depths > 16 m. This indicates that the study area is not a good aquifer zone. Keywords: Resistivity, Landfill, Leachate, Groundwater, Dumpsite, Aquifer, Sounding

A two dimensional (2D) geoelectrical tomography of Ahmadu Bello University Teaching Hospital Premises was carried out with the aim of identifying a suitable location for siting a borehole. This was sequel to the fact that a borehole drilled without proper geophysical investigation in the quarters for resident doctors did not produce water. State-of-the-art equipment was employed and 2D surveying proved a powerful geological mapping tool, for use in hydrogeological mapping including engineering and environmental applications. The 2D inversion results of the survey were correlated with the lithology information obtained from the boreholes in Jama'a village, and the hostels and the residential quarters of ABUTH. The stratigraphic structure of the study area is very complex and is a product of volcanic and magmatic activities of various ages. Based on the geo-electrical images obtained in the study area, three distinct layers were revealed, the overburden with an average thickness of about 16 m-26 m. The overburden is immediately underlain by the weathered basement, 5 m-14 m thick which consists of disintegrated schistose rock materials, sand and gravel. This layer has a relatively low resistivity due to the presence of water and clay, which reduces the permeability, so this layer is thus regarded as the aquifer. The fresh basement rock was encountered at a variable depth of between 21 m and >30 m with resistivity 1223 Ωm up to 11918 Ωm. These results agree with the borehole logs. The complete set of borehole logs used in this research were obtained from the original hydro-geologic assessment report of the groundwater research department of the National Water Resources Institute (NWRI),