Geoelectric Characterization of Igbo Oritaa Archaeological Site, Iwo, Southwestern Nigeria

Fadare, T, Oni AG, Olorunfemi M, Ogunfolakan B.  2020.  Geoelectric Characterization of Igbo Oritaa Archaeological Site, Iwo, Southwestern Nigeria, 2020/05/16. 21:333-344.


Electrical resistivity survey was carried out at Igbo Oritaa archaeological site in Iwo, Southwest Nigeria, with a view to providing information on the locations of buried artifacts that will aid followup excavation works and subsequent recreation of the historical activities at the ancient settlement.Within the upper 1.5 m, thirty-one (31) anomalous zones suspected to be of archaeological interest were identified from depth slice resistivity maps. Twenty-one (21) of these were high resistivity zones while ten (10) were low resistivity zones. Suspected archaeological artifacts include collapsed huts, iron smelting site, tomb, ancient dumpsites, and collapsed ancient wall. These artifacts were identified based on their geoelectric characteristics. Clustered high resistivity anomalous zones C, D, and E characterized by resistivity values greater than 120 ohm-m, were interpreted as suspected mini settlements. The low resistivity anomalous zones iii, iv, v, vii, viii, ix, and x within or close to the suspected settlements were attributed to ancient dumpsites. The elongated high resistivity anomalous zone F with resistivity values ranging from 120 – 200 ohm-m was attributed to tomb. High resistivity (200 – 400 ohm-m) anomalous zones C5, C6, D3, D4, F, and G aligned parallel to the delineated ancient trench were attributed to relics of a collapsed ancient wall.
Two of the recommended eight sites, sites 4 (Pit 1) and 5 (Pit 2), characterized by high resistivity closures were excavated. Artifacts recovered from these sites were pottery sherds, snail shell, animal jaw bone, cowries, flute, iron objects, glass beads, bones fragments, bone bead, metallic and bronze objects, oyster shells, finger like clay cylinder, and relics of a structure (hut) foundation. The recovered artifacts confirmed Igbo Oritaa as an ancient settlement occupied by people whose social, economic, dietary, and cultural activities were reflected by the archaeological finds.