LINEAMENTS MAPPING FOR HYDROGEOLOGICAL STUDY USING AEROMAGNETIC AND PSEUDOGRAVITY DATA: A CASE STUDY OF LAFIAGI, SOUTHWESTERN NIGERIA

Abstract

Lineaments mapping over a part of the transition environment between the Basement Complex rocks of the southwestern Nigeria and the Sedimentary rocks of the Nupe Basin was carried out. It was aimed at identification of the structural features responsible for the hydrogeology of the area. This work involved the qualitative and quantitative analysis of aeromagnetic and pseudo-gravity data using Oasis MontajTM and the geological data using Rockwork15TM software. The 2-D Forward modeling and inversion of the acquired aero-magnetic and pseudo-gravity data augmented with geological information obtained from reliable sources were employed in the lineaments extraction and interpretation works. The results have shown that the identified faults and lineament features obtained from geophysical data generally coincide with the river channels on the geologic and drainage maps which indicate a structural control of the drainage system in the study area. The rose diagram of the extracted faults and lineament features showed a preponderance of NE/SW trend followed by NW-SE and N-S trends.