Geothermal Reconnaissance of Southeastern Nigeria from Analysis of Aeromagnetic Data
The West African Rift System led to the formation of the Benue Trough in Nigeria, creating sub-basins within the Trough. These basins were subjected to synsedimentary tectonic deformations during Cretaceous to Neogene times and were affected by magmatic—volcanic episodes leading to multiple areas of geothermal anomalies within sedimentary basins. We performed a geothermal reconnaissance of the lower Benue Trough using aeromagnetic data. Estimates of depths to the bottom of magnetized crust (assumed Curie point depth) were determined from spectral analysis of magnetic anomalies. The estimated average Curie point depth in the region is 13.16 ± 1.20 km with an average geothermal gradient of 46.04 ± 1.45 °C km−1. The average geothermal gradient reckoned from our estimated CPD data is in agreement with average geothermal gradient achieved from deep wells drilled in the region for oil exploration. Results are useful for further geothermal explorations in the region.
KeywordsCurie point Magnetic anomaly Geological structures Geothermal gradient Heat flow