Geoelectric survey was carried out in the eastern part of Usmanu Danfodiyo University main campus with the aim of determining areas that are suitable for drilling boreholes. Thirty Vertical Electric Soundings were made at different parts of the area using the Schlumberger electrode spread arrangement with maximum half-electrode spacing of 100 m. Qualitative interpretation of the curves suggested thirteen different curve types highlighting that the area is underlain by three to six layers; the top soil predominantly lateritic in composition and occasionally wet, the fresh laterite, shale and limestone layer , the shale, limestone and sandstone layer, clayey sand, coarse sand, shale, limestone and sandstone layer and the fine sandstone and limestone layer. Using the measured current and voltage, apparent resistivity, thickness, depth, hydraulic conductance, transmissivity and protective capacity maps of the aquifers in the area were generated. Based on comparison of groundwater potential zones on these maps, an integrated groundwater potential map of the area was inferred and used to classify the area into low, moderate and high groundwater potential zones. Three zones in the south-central, east-central and extreme northeastern parts were inferred to be suitable for drilling boreholes in the study area.
Key words: Vertical electrical sounding, Hydraulic conductance, Transmissivity, Aquifer protective capacity, Groundwater potential map
|
