Evaluation of Curie-point depths, geothermal gradients and near-surface heat flow from high-resolution aeromagnetic (HRAM) data of the entire Sokoto Basin, Nigeria
Journal of Volcanology and Geothermal Research
Department of Geophysics, University of Ilorin, Ilorin, Nigeria; Physics Unit, Centre for Preliminary and Extra-Mural Studies, Federal University of Technology Minna, Nigeria
An evaluation of Curie-point depths, geothermal gradients and near-surface heat flow has been carried out from the spectral analysis of the recently acquired high resolution aeromagnetic (HRAM) data of the entire Sokoto Basin in northwestern Nigeria. The HRAM data was divided into twenty two (22) overlapping blocks and each block analyzed using the spectral centroid method to obtain depth to the top, centroid and bottom of magnetic sources. The depth values were subsequently used to evaluate the Curie-point depth (CPD), geothermal gradient and near-surface heat flow in the study area. The result shows that the CPD varies between 11.13 and 27.83km with an average of 18.57km, the geothermal gradient varies between 20.84 and 52.11°C/km with an average of 33.99°C/km, and the resulting heat flow varies between 52.11 and 130.28mWm-2 with an average of 84.97mWm-2. Such heat flow values are suggestive of anomalous geothermal conditions and are recommended for detailed geothermal exploration in the basin. © 2015 Elsevier B.V.
Curie temperature; Geothermal energy; Geothermal prospecting; Heat transfer; Spectrum analysis; Aeromagnetic data; Curie point depths; Geothermal exploration; Nigeria; Sokoto basin; Magnetic prospecting; aeromagnetic survey; Curie point; geothermal system; heat flow; spectral analysis; temperature gradient; Nigeria; Sokoto Basin; Calluna vulgaris