Application of 2D and 3D Geoelectrical Imaging for Site Investigation at Proposed Hotel Building Site in Benin.

Abstract

At the planned location of a four-star hotel project in Benin City, Edo State, geophysical investigations using 2D and 3D electrical resistivity imaging techniques were conducted to study the nature of the subsurface structure and assess its Suitability for the superstructure building. Finding the depth of the bedrock and any potential faults, fractures, voids, or clay that can endanger the structures that were supposed to be built are the primary goals. Using the Wenner arrangement, ten (10) high-resolution 2D electrical resistivity pictures were obtained, with minimum electrode separation of 5m and profile separations of 10m. The 200m constant profile length for each line was covered using the roll-along technique. The collated resistivity data was processed and inverted using the RES2DINV software. The 3D Imaging was gotten by combining and inverting the 2D resistivity data. A profile length of 200m was achieved from each profile and a depth of 39.6m was probed. The surveyed are showed suspected accumulation of Laterite, Clayey soil at the top soil with resistivity ranging from 120ohmm to 250ohmm, and a highly compacted middle layer which extends to the based of the surveyed site suspected to be Compacted laterite, sandstones and ferruginized soils. The study area was confirmed to be suitable for the proposed Hotel as no Fractures, Voids and Accumulation of Clay materials were found.