D.C. RESISTIVITY INVESTIGATION OF SUBSURFACE LAYERING FOR GEOTECHNICAL APPLICATION IN MILLENNIUM CITY, KADUNA, KADUNA STATE.
Abstract
Vertical Electrical Sounding (VES) method of Direct Current Resistivity was -carried out at the South Eastern part of the Millennium City, Kaduna, Kaduna State, North-Western, Nigeria using the Schlumberger array, with the aim of obtaining information on the subsurface layering for geotechnical application. From the interpreted data, geoelectric and geologic sections and some specialized maps were produced. It is suggestive that the area is underlain by three to five layers. The first layer resistivity and thickness are found to range from 66Ωm to 8343Ωm and 0.39m to 9.4m respectively. The weathered/fractured basement layer, which forms the aquifer, is found to have resistivity and thickness ranging from 36Ωm to 656Ωm and 10.0m to 48.7m respectively. The basement, which forms the final layer, having an infinite thickness, is found to have resistivities ranging from 1016Ωm to 14399Ωm. Competent zones for geotechnical applications within the study area were found to be at VES L1/2, VES L1/3, VES L1/4, VES L1/5, VES L1/6, VES L2/3, VES L2/4, VES L2/5, VES L3/2, VES L5/1 and VES L5/2. VES L1/3 was however, found to possess all the characteristics of competence in relation to surface resistivity, first layer thickness, basement resistivity and depth to basement and hence was considered to be the most competent.
