Sixty nine electrical resistivity soundings were conducted around Mangu Town and its immediate environs for groundwater potential assessment within the Basement Complex of the Jos Plateau. A computer aided interpretation of the VES data enable the identification of geoelectric layers/geologic units like- Topsoil, laterite, weathered basement and bedock which have hydrogeologic significance in groundwater development. Resistivity value range from 12 to 2079 ohm-m, 255 to 609 ohm-m, 30 to 503 ohm-m, and ≥ 120 ohm-m to infinity in the topsoil, lateritic layer, weathered layer and bedrock. Layer thickness also vary from 0.2-3.5m in the topsoil, 0.4-8.5m and, 0.6-35m in the lateritic and weathered layers respectively. The depth to bedrock (basement) range from 0.2-35m across the study area. Based on the VES interpretation, geo-electric/lithologic sections, bedrock relief and isopach maps were modeled; these models assisted the classification of the groundwater zones into low, medium and high potential areas. It is established from this study that zones with thick overburden thickness within depressions have good groundwater potential. Expectantly, the result of this stud

An integrated geophysical and hydro-geological investigation was carried out at the University of Ibadan campus, southwestern Nigeria, with the aim of delineating prospect areas with high groundwater potential. The study area is underlain by quartzite/quartz schist, banded- and augen- gneisses with minor intrusions of pegmatitic vein and dolerite dyke. One hundred and thirty eight Vertical Electrical Soundings (VES) and ten Radial Vertical Electrical Soundings (RVES) were carried out and complemented with information from seven boreholes. The result of the VES data revealed three to five geoelectric layers; the top soil (56 - 1143 Ωm), clayey soil (15 - 271 Ωm), lateritic soil (346 - 1656 Ωm), weathered basement (8 - 242 Ωm) and the fractured (8 - 709 Ωm) /fresh bedrock (534 - 8128 Ωm) while the overburden thickness ranges from 1.2 - 63.2 m. Reflection coefficient at the bedrock interface ranges from 0.01 - 0.99. Borehole logs showed a good correlation with the geoelectric layers. The RVES data indicated a significant presence of electrical resistivity anisotropy while graphical interpretation of the data identified fracture systems at different depths with orientation of the fractures in the N-S, NE-SW, NW-SE and W-E directions. The coefficient of anisotropy ranges between 1.00 and 1.68. The iso-resistivity and isopach maps of the overburden and bed rock relief shows that areas with shallow overburden thickness corresponds to bedrock ridges while areas with thick overburden thickness corresponds to bedrock troughs. The results of the geophysical investigation showed that prospect for groundwater development in areas underlain by quartzite/quartz schist is invariably high while in areas underlain by banded - and augen- gneisses, groundwater is controlled mainly by the overburden and the presence of fractures in the bed rocks.

An attempt to determine the suitability of groundwater for domestic purpose was undertaken. The area is underlain by the Precambrian Basement Complex Crystalline rocks which include; porphyritic granite ,mica schist, porphyroblastic gneiss and migmatite which are fractured predominantly in NNE-SSW directions. These structures have effect on the drainage pattern and influence both the groundwater and surface water flow directions in the area. A total number of forty (40) water samples from twenty (20) locations were collected and analysed. The results show the pH values range from 5.66 - 7.24, conductivity from 40 - 800 μS/cm, total dissolved solids from 26.8 - 556.1 mg/l which are within the range of permissible limit stipulated by both the NIS and WHO standards for drinking water quality. Other parameters analysed show K+ to range from 20 – 115 mg/l, Ca2+ from 3.275 – 118.276 mg/l, Mg2+ from 1.721 – 65.247 mg/l, Na+ from 3.6 – 113 mg/l, HCO3- from 70.7 – 838.3 mg/l, Cl- from 0.0 – 0.43 mg/l, SO42- from 0.0 – 41 mg/l, NO3- from 0.0 – 35 mg/l, Fe2+ from 0.115 – 4.752 mg/l, Zn+ from 0.006 – 0.153 mg/l, Mn+ from 0.0 – 1.049 mg/l, Cu2+ from 0.007 – 0.15 mg/l and NH3- from 0.02 – 1.2 mg/l. The water type of the area is Ca-(Mg)-HCO3 based on Piper and Schoeller diagrams, and the dominant ion is HCO3 while the least is Cl based on Wilcox diagram. Groundwater in the study area is good for drinking and other domestic uses based on the comparison with NIS and WHO standard for drinking water quality. The water is also suitable for livestock and irrigation purposes.

A total of fifty samples were collected from six different locations at Oke – Ebu and Oke- Osun artesian wells in Ikere Ekiti, Southwestern Nigeria for hydrochemical analysis. The objective of this study is to determine the physico-chemical properties of water collected from Ikere-Ekiti artesian well so as to identify the possible contamination levels. The samples collected were subjected to field and laboratory analysis to determine the physiochemical and microbial characteristics with special reference to strict academic and industrial research standards. The analyses include the use of Membrane Filtration techniques, Versenate filtration method, Multiple Tube Methods and Atomic Absorption Spectrophotometer respectively. The result shows that the pH value of the samples range from 7.0 to 7.3 while the colour possessed by the water samples is objectionable. The temperature of the samples has an average value of 27OC and the electrical conductivity result shows that the range falls between 360 and 485μs/cm respectively. The turbidity results indicate that over 90% fall within the WHO admitted value of 5NTU. The chemical composition of the water samples indicate the concentration of iron falls within the range of 0.11mg/l to 0.66mg/l while dissolved oxygen ranges from 310mg/l to 362mg/l respectively. Also sulphate content falls within 54 and 84 mg/l while chloride falls 2.6 -5.5 mg/l respectively. The bacteriological analysis results, indicated the presence of faecal streptococci and pseudomonas aeruginosa. The microbiological results obtained showed that the quality of the well water does not agree with the National food and drugs control (NAFDAC, 2007) and World Health Organisation (WHO, 2009) standard of drinking water. This is a consequence of high concentration of contaminant indicators, higher than NAFDAC and with specifications. The analysis becomes important because water from these artesinal wells is used for domestic purpose by the whole community of Ikere Local Government area of Ekiti State.