ABSTRACT
Electrical resistivity measurements using the vertical electrical sounding (VES) technique were employed for the determination
of soil competency for construction purpose at southern part of Gulumbe district Kebbi state NW Nigeria. Thirty-three vertical
electrical sounding (VES) points were investigated with a maximum AB/2 spacing of 100m within an area of 500 by 500m.
Resistivity sounding curves are found to be “H”, “A”, “K” and “Q” types, i.e. 1- A, 18- H, 3- K and 11- Q types respectively.;
predominantly with “H” type constituting about 65% of the survey points. The study reveals that the subsurface lithologic
units in the area were dominated by three- four geo-electric layers that comprise of topsoil (pink clay, ironstone & browns
clay), The relatively high apparent resistivity range of the topsoil (157.6 - 3538 Ohm-m) ironstone, fine sand, sandstone, white
clay & coarse sand (103 – 7724 Ohm-m) respectively indicate that the underlain rock units are competent and therefore can
withstand heavy structures and thus recommends that the suitable zones for high rise structures should be located on northern,
eastern and SW part of the study area