Geopressured-Geothermal System Potential of the Nigerian Chad Basin, Northeastern Nigeria: Implications for Deep Sedimentary Basin Energy Resources

Abstract

The geopressured-geothermal potential of the Nigerian sector of the Chad Basin remains largely unexplored. This study evaluates the suitability of the basin for geopressured-geothermal energy development through an integrated assessment of its thermal regime, sedimentary architecture, reservoir characteristics, sealing formations, and structural framework. Available geothermal data indicate thermal gradients ranging from approximately 24 to 61 °C/km and heat-flow values between 60 and 156 mW/m², suggesting localized thermal anomalies within the basin. Stratigraphic analysis reveals the presence of thick sedimentary successions exceeding 5 km, with extensive sandstone reservoirs within the Bima and Gongila formations overlain by regionally extensive shale units that may act as effective thermal and hydraulic seals. Structural evaluation indicates that basement-rooted faults and fracture systems provide potential pathways for upward heat transfer and fluid migration. The central and eastern sectors of the basin exhibit the most favourable combination of thermal gradients, sediment thickness, reservoir development, and structural complexity. Comparison with established geopressured-geothermal provinces such as the Gulf Coast Basin (USA), the North German Basin, and the Pannonian Basin indicates that the Nigerian Chad Basin possesses several geological characteristics required for commercial geopressured-geothermal development. The study demonstrates that the basin constitutes an underexplored renewable energy resource that could contribute to future energy diversification and energy security in Nigeria.