Pre-foundation geophysical investigation of a site for structural development in Oka, Nigeria

Frequency of structural failure globally has necessitated geophysical investigation subsurface geology a site for engineering construction works. Combined very low frequency electromagnetic (VLF-EM) and electrical resistivity methods were used to provide detailed information on subsoil profile documentation references durable sustainable Thirteen traverses established from which data acquired. Major conductive geological interfaces suspected be faults/fractured zones identified the plots VLF-EM data. These points serve as 50 sounding stations further investigated using Schlumberger electrode array with vertical technique imaging selected four site. The acquired processed, inverted interpreted. 2-D models revealed at some locations suggesting incompetent zones, responsible instability. Saturated clayey uneven bedrock topography depressions could cause differential settling negative impact structures. Structural may arise existence concealed structures, deep weathering/fractured bedrock, heterogeneous structurally deformed (F1–F16) setting. Thus, classified unstable sections are considered priority in design mitigate unforeseen challenges. Deep foundations form piers piles encouraged avert failure.