Science Journal of Physics
March 2013, Volume 2013, ISSN:2276-6367
© Author(s) 2013. This work is distributed under the Creative Commons Attribution 3.0 License.
Resistivity Survey for Groundwater in Ezza North Using Vertical Electrial Sounding
1Offiah S. U., 2Obiora D. N., 2Chukudebelu, J. U. and 2Ezema P. O.
1National Centre for Energy Research and Development, University of Nigeria Nsukka
2Department of Physics and Astronomy, University of Nigeria Nsukka
Accepted 23 February, 2013; Available Online 21 March 2013
Vertical electrical resistivity soundings were conducted in order to delineate the groundwater potentials at some locations in Ezza North Local Government of Ebonyi State. Twelve vertical electrical soundings were obtained using the Schlumberger configuration with the aid of the OHMEGA terramenter (SAS1000).The field data were subjected to interpretation by employing the method of manual partial curve matching techniques using the master curves and the corresponding auxiliary curves. A computer programme (RESOUND) was also used to interpret the data. The parameters obtained were used to determine the resistivities and thicknesses of the subsurface layers. The major lithologic units of the area are shales, sandstone and mudstone. The water bearing rocks were interpreted to exist at depths between 20m and 130m. The results fairly correlated with some logged boreholes close to the survey area. The aquifers have resistivities ranging between 9Ωm and 110Ωm. The geophysical search for groundwater has shown that the survey area has good groundwater potentials which if exploited would go a long way in reducing the problems of seasonal water shortage and health problems associated with the consumption of unhygienic surface water in the area.
Keyword:Resistivity, VES, groundwater, terrameter, geoelectric layer, aquifer