Structurally Failed Dam: A Case Study of Cham Dam, North-Eastern Nigeria

Abstract

A geophysical investigation involving Shlumberger vertical electrical sounding (VES) profiling was conducted on a failed dam in Cham area, Upper Benue Trough, North eastern Nigeria. The raw VES data were used to prepare apparent resistivity curve, pseudosection and the geoelectric section along considered six VES points. The study indicates the subsurface as remarkably in-homogeneous in geologic composition. The geologic layers are defined by variable combination of siltstone, shally-clay, claystone, shale and clay which constitute the subsurface. The investigation indicated displacement at depth which correlates well with the failed segment of the dam. It is concluded from the study that the dam under investigation probably failed on account of displacement along suspected weak zones.

Keywords: Geophysical,Shlumberger VES, Dam, Displacement