Geothermal Energy Resource Potential Investigation of the Southern Benue Trough using High-Resolution Aeromagnetic Data

Abstract

Nigeria's commitment to decarbonizing its energy sector and achieving net-zero 
greenhouse gas emissions by 2060 has intensified the search for sustainable and 
cleaner alternative energy resources, including geothermal energy, to support long
term economic development. However, geothermal exploration within frontier basins 
such as the Southern Benue Trough (SBT) remains constrained by the absence of deep 
borehole temperature data required for detailed characterization of the subsurface 
thermal regime, as well as the complex geological framework controlling regional heat 
flow distribution. This study employed high-resolution aeromagnetic data as an 
indirect geophysical approach to evaluate the geothermal energy potential of the SBT 
through the estimation of Curie Point Depth (CPD), geothermal gradient (GG), and 
heat flow (HF). The estimated CPD values range from 3.73 to 15.56 km, with an 
average of 10.99 km, reflecting considerable spatial variability in crustal thermal 
structure. Correspondingly, geothermal gradient values vary between 37.28 and 
155.50 °C km⁻¹, averaging 58.34 °C km⁻¹, while calculated heat flow values range from 
93.19 to 388.74 mW m⁻², with a mean of 141.85 mW m⁻². The northeastern sector of 
the SBT is characterized by anomalously shallow CPD values that spatially coincide 
with elevated geothermal gradients and heat flow, indicating enhanced subsurface 
thermal conditions and significant geothermal resource prospectivity. These findings 
demonstrate the effectiveness of aeromagnetic-derived thermal parameters for 
geothermal assessment in data-limited frontier basins. The study provides a robust 
geophysical framework to guide future geothermal exploration and resource 
development within the Southern Benue Trough and other geological provinces sharing 
comparable tectono-thermal evolution.