Geologic mapping and basement–sediment contact delineation along Profile X, Igarra–Auchi area, Southern Nigeria using ground magnetic and electromagnetic methods

Abstract Outcrop mapping as well electromagnetic and ground magnetic surveys was carried out within Auchi Igarra localities in order to attempt an interpretation of the geology areas delineate boundary between basement sedimentary terrains. Geologic done by collecting samples outcrops at five different locations areas. Three lithofacies were identified area they are basal shale unit, tabular cross-bedded sandstone unit ferruginized unit. The pebbly is greyish black colour; white, coarse-grained base finer top with pockets clay, while dark red. Rocks Precambrian complex underlie area. underlain metasediments that have been intruded igneous rocks. Results show presence three major groups metamorphic rocks area, migmatite–gneiss complex, porphyritic granites. data acquired along Profile X located Auchi–Igarra–Ibillo road processed using Microsoft Excel Software resulting plots delineated lower electrical conductivities higher susceptibilities, susceptibilities. susceptibilities interpreted be rocks, also most likely basement–sedimentary