Application of Remote Sensing and Geophysical Methods for Delineating Groundwater Potential at North Western Nigeria

Abstract

Abstract The hydrogeological environment can be mapped and groundwater zones identified by combining geophysical and remote sensing methods. In the Palladan and Basawa region of Sabon-Gari local government area in Kaduna state, northwest Nigeria, subsurface features that serve as conduits for groundwater flow are identified and removed using an integrated methodology. The analytical hierarchy process (AHP) was used to enhance, weight, prioritize, and rank a number of remote sensing and geographic datasets. A GIS platform was then utilized to integrate thematic data and create a groundwater potentiality zonation (GWPZ) map. Topographic lineaments in the area are brought to light in remote sensing data using the lineament extraction technique. Based on the lineament density map, the distribution of these lineaments reveals the degree of porosity or permeability in each area and, consequently, its groundwater potential. Aeromagnetic data filtering permits the construction of a structural map that illustrates various geophysical lineaments that are known to be fault systems in the research area. These faults are the main routes via which groundwater seeps to the subsurface and granitoid-type magnetic rocks intrude into the basement. The research region is badly fractured/failed and made up of four lithologic units, including the aquifer layer (clayey sands in the cracked basement) with thicknesses varying from 12–55 m, according to the vertical electrical sounding (VES) applications. According to geoelectric cross-sections, the subsurface structures are made of granitic rocks that are surrounded by normal faults that trend both NW and NE. It is believed that groundwater flows into the hard rock aquifers in the studied locations through these notable geological features, such as faults and fractures.