Multi-structural Mapping of Subsurface Geological Features in Omu-Aran and Environs using 3D Euler Deconvolution of Aeromagnetic Data

Abstract

High-resolution aeromagnetic data over Omu-Aran and its environs have been analyzed to map different types of subsurface geological structures in the area. The data were filtered by upward continuation and then subjected to 3D Euler Deconvolution (ED) using multiple structural indices, which range from 0 to 3. The filtered map showed slightly smoother anomalies, which indicate an increased signal-to-noise ratio. The Euler solutions obtained showed the locations, orientation and depths of different types of geological structures, including contacts, faults, pipe-like structures, and spherical/compact bodies. These solutions were compiled to produce a geological structural map for the study area. The geological structures having high structural indices were mostly located at deeper depths than those having low structural indices. The results also showed that the geology of Omu-Aran and its environs is highly structurally dissected by faults and dike-like structures, among other geological structures. The subsurface structures trend dominantly in the NNE-SSW and ENE-WSW directions. Five potential zones of high structural complexity were identified and two fault zones oriented in the NNE-SSW and ENE-WSW directions were also mapped. The NNE-SSW fault zone was considered a part of the Ifewara Fault zone. The dominant trending structures in the study area were attributed to the continental extension of Atlantic Fracture Zones and Pan-African Orogeny. The geological structures identified in the study area were recommended as potential targets in the search for mineral deposits and for regional groundwater prospecting in Omu-Aran and its environs. The fault zones identified in this study were, however, not recommended as locations for siting man-made infrastructure such as buildings and bridges.