Investigating geothermal energy resource potential in parts of south western Nigeria using aeromagnetic data

Abstract

The investigation of geothermal energy resources potential in this study involves delineating targets areas of the earth’s crust where geologic processes have raised temperatures near the surface, such that the heat contained can be utilised. A high-resolution aeromagnetic (HRAM) data of part of south-western Nigeria on longitude 3.5° ?? 5.5° and latitude 7.0° ?? 9.0° consisting of 16 half degree sheet was used for this research work. Spectral analysis was applied in processing HRAM data, which transforms the spatial data into the frequency domain, and provides a relationship between the two-dimensional spectrum of the magnetic anomalies. Results indicates that the average Curie point depth (CPD) within the study area is 8.5 km followed by the average geothermal gradient of 42.5℃??⁻¹ and an average heat flow 55 ???⁻². The equitable promising geological results useful for geothermal exploitation is within longitude 4.2° ?? 4.6° and latitude7.8° ?? 8.2°, where the lowest CPD (5.5km), highest geothermal gradient (75℃??⁻¹) and highest heat flow (190???⁻²) bounded by Oshogbo and Ogbomosho as indicated on the maps. The paper suggests that such an area can be considered for geothermal energy exploitation since the demagnetized of magnetic rocks confirms a hot rock who’s temperature of about 580℃.