Identifying Potential Aquifers Using Landsat Images, Aeromagnetic And Resistivity Responses In Panyam, Plateau State, Nigeria

The study involves delineation of aquifers in Panyam and its environs, North Central Nigeria. This study can serve as a useful guide for groundwater development projects which may be put in place to cater for water needs of dwellers. Methods employed include; geological mapping of the area, field acquisition of electrical resistivity data using 1D vertical electrical sounding of nine (9) stations, acquisition of aeromagnetic data and interpretations of total magnetic intensity (TMI) maps, as well as analysis of lineaments generated from remotely sensed aerial photographs of the area. Exposed in the study area are basement rocks comprising of granitic gneisses, basalts and granites with evidence of deformation shown as joints, fractures and veins in places. Interpreted resistivity data shows a three layer case for VES 1 to 5, comprising of topsoils, weathered regoliths and fresh basement with resistivity ranges of 321 Ωm to 1572 Ωm, 126 Ωm to 365.1 Ωm and over 290000 Ωm respectively. VES 6 to 9 comprise of five layers, with the presence of a fractured zone, with resistivity range of 59.4 Ωm to 676 Ωm. The weathered and fractured layers constitute the aquiferous units in the area with the fractured zone being the main aquifer, owing mainly to its appreciable thickness of up to 30 to 50 m. TMI maps classify the study area as a magnetic high area, showing evidence of uplift in surrounding basement rocks which could have lead to the development of structures as depicted by abundance of NE-SW trending lineaments derived from aerial photographs. The occurrence of lineaments correlates with electrical resistivity data, which points to deep sited fractures as main aquifers in the area. Based on the study, the area has moderate to high groundwater potential. Groundwater exploitation in economic quantity will be more feasible for fractured aquifers at depths of up to 30 to 50 m.