Electrical Resistivity Survey For Conductive Soils At Gas Turbine Station, Ajaokuta, SW, Nigeria
AbstractTen (10) vertical electrical soundings (VES) using Schlumberger configuration were carried out to delineate subsurface conductive soils for the design of earthling grid for electrical materials installation at the Gas Turbine Station, Ajaokuta, SW Nigeria.
Interpretation of the resistivity data revealed three major geoelectric layers namely; topsoil, clay, and partially weathered/fresh basement. The topsoil and the clay layers are the main conductive media in the study area.
The conductivity of the topsoil varied from 0.0068 to 0.0833mho.m-1 It is generally conductive with a slightly resistive area beneath one of the VES stations. However the top layer is relatively thin (0.5-4.0m). The underlying layer is made up of clay that is very conductive. Its conductivity varies from 0.0098 to 0.0909 mho.m-1 The thickness of this second layer is considerable (3.4-25.7m) and should be able to neutralise external charges. Therefore the first and second layers are recommended for earthling of the electrical materials. The recommended depth for the earthling is between 1.5 and 2.0m. This depth is within the conductive topsoil and a very conductive clay layer underlies it. The third layer in the study area is the partially weathered/fresh basement. It is highly resistive within the region and it is not recommended for earthling.
KEY WORDS: Electrical Resistivity, Conductivity, Earthling.
Global Journal of Geological Sciences Vol.3(1) 2005: 55-59