PRELIMINARY GEOPHYSICAL INVESTIGATION OF IGBAJO ARCHAEOLOGICAL SITE, SOUTHWESTERN NIGERIA

Abstract: The integration of Ground Penetration Radar (GPR), magnetic and electrical resistivity methods revealed detailed and cost effective identification of zones of potential archaeological interest at the theatre of war in Igbajo. The Ground Penetrating Radar (GPR) were acquired using the GSSI SIR 3000, the magnetic method were acquired using the proton precession magnetometer while Ohmega resistivity was used to acquire the electrical resistivity data. The applications of geophysical method to delineate the depth and locations of archaeological materials have been demonstrated. The result of the magnetic survey showed regions of high magnetic intensity which indicates the existence of certain buried artifacts; this assisted in the gridding of the Ground Penetrating Radar (GPR) profiles. Significant features were observed on the radargram which correlates with high resistivity anomalies observed on the inversion profile. It was observed that a region of high resistivity values on the inversion coincides with the ground penetrating radar on the radargram. The results show that the region with the highest resistivity between 510 - 54959 Ohm-m and at depths between 0.5-3 m from the resistivity inversion indicates the possible presence of artifacts which can further be confirmed through excavation

Keywords: Ground Penetrating Radar (GPR), geophysical, Geophysical Survey Systems, Inc. (GSSI), GPS