Spatial mapping of potential geothermal areas is an effective tool for a preliminary investigation and the development of a clean and renewable energy source around the globe. Specific locations within the Earth’s crust display some manifestations of sub-surface geothermal occurrences, such as hot springs, a volcanic plug, mud volcanoes, and hydrothermal alterations, that need to be investigated further. The present area of investigations also reveals some of these manifestations. However, no attempt was made to examine the prospectivity of this terrain using the efficient GIS-based multicriteria evaluation (MCE) within the scope of the Analytic hierarchy process (AHP). The integration of remote sensing, Geographic information system (GIS), and other geophysical methods (Magnetic and gravity) was performed to map the promising geothermal areas. Multiple input data sets such as aero-magnetic, aero-gravity, aero-radiometric, digital elevation model (DEM), geological map, and Landsat-8 Operational Land Imager (OLI) data were selected, processed, and use to generate five thematic layers, which include heat flow, temperature gradients, integrated lineaments, residual gravity, and lithology maps. The five thematic layers were standardized and synthesized into a geothermal prospectivity map. The respective ranks and weight of the thematic layers and their classes were assigned based on expert opinion and knowledge of the local geology. This research aims to apply an efficient method to evaluate the factors influencing the geothermal energy prospects, identify and map prospective geothermal regions, and, finally, create a geothermal prospectivity model.

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The study area is located in the northwestern part of the Adamawa massif of northeastern Nigeria and lies between longitude 11 0 50 / E and 12 0 00 / E and latitude 8 0 49 / N and 8 0 55 / N. Lithologies of the area include: granite-gneisses, porphyritic granites, and biotite hornblende gneiss. A G-856 Memory-Mag TM proton precision magnetometer was used to acquire ground magnetic data of the area following a regular grid pattern. The magnetic data were subjected to diurnal correction and contoured using Surfer 11surface mapping software to produce a magnetic map. Areas characterized by anomalous magnetic values (34342 -34348 nT) are interpreted as areas of iron occurrences. The computer software WingLink was been used to generate 2-D subsurface geologic models for the computation of the depths to the anomalous bodies. The average depth to the source of anomalous bodies is 351.67 m, which is interpreted as average depth to iron mineral occurrence. Ground geologic mapping confirmed areas of surface iron occurrences as veins in granite gneiss. Geological investigation of the discovery is suggested to determine the tenor and tonnage for possible economic exploitation as part of Nigeria's government plan to revitalize the solid mineral/mining industry.