An electrical resistivity investigation was carried to investigate the bedrock geometry of the northern part of Kujama Prisons Farm Kaduna using the Vertical Electrical Sounding (VES) method. The study is aimed at obtaining information on the subsurface layering for future civil engineering works. The area covered was 200,000 sqm having five (5) profiles with six (6) geophysical investigative points on each profile and separated 100m apart. Ohm-Mega resistivity meter was used for the Vertical Electrical Sounding (VES) and Thirty (30) points where established. To interpret the VES data, Res1D iterative software, Surfer 11 and Oasis Montaj software’s were used and it revealed three to five subsurface layers having Topsoil thickness between 0.3 − 2mand resistivity between 104 − 4824 Ωm also, the last layer considered as the weathered/fractured/fresh basement has an infinite thickness with resistivity ranging from 45 – 10173 Ωm and the average overburden thickness of the area found to be 17.8m. The VES found fresh basement at points A3(6151 Ωm), A6(5089 Ωm), B3(1067Ωm), E5(10173 Ωm) and E6(1100 Ωm). From the study it is suggestive that the bedrock geometry has been irregularly configured over geological times due to effects of intense weathering. Therefore, the investigation revealed the study area may be considered for civil works of low bearing capacity.
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