Abstract

2D electrical resistivity tomography was observed at Ile-ife seismographic station, Osun state Nigeria with the aim of investigating the geological structures beneath the station in order to identify areas of anomalous resistivity that might be related to fractures or fault lines and also determine the lithology of the subsurface. This is to ensure that data observed by the seismic station are gotten with less noise. The underground conditions at a station influence both the seismic signal and the noise conditions and thus have a significant bearing on the potential sensitivity of a seismic station. The survey was carried out with Terrameter SAS 1000 and ES 464 electrode selector equipment. Dipole-dipole configuration at electrode spacing of 2m was used to acquire the data. The result showed that the station is underlain by three layers; overburden composed of lateritic clay, clayey sand, the weathered and fresh basement. Fault lines and fractured zones were not observed in all profiles. The result was also compared with bedrock quality grades, which further inferred best sites for seismic station based on the lithology of the area..

Keywords:Seismic station; ER