Structural mapping for groundwater occurrence using remote sensing and geophysical data in Ilesha Schist Belt, Southwestern Nigeria

Abstract

This research was carried out to evaluate structural analysis for groundwater potentiality using an integration of satellite remotely sensed, aeromagnetic dataset, and vertical electrical sounding (VES) in Ilesha Schist Belts, Southwestern Nigeria. Filtered and enhanced Landsat 8 OLI satellite imagery and aeromagnetic dataset were analyzed and used to generate lineaments in terms of groundwater prospects. The extracted lineament from Landsat 8 OLI satellite imagery and the aeromagnetic datasets was predominantly NE-SW orientations. The lineaments extracted were superimposed to determine lineament intersection and subjected to line density to generate the lineament intersection density. The lineament intersection density was categorized into four categories such as very low, low, moderate, and high. The VES acquired on the categorized lineament intersection density zones was used to validate and ascertain the usefulness of lineament intersection density for groundwater development. Five major curves were identified within the study location such as A, H, KH, HA, and HKH. The VES curve types were grouped into three aquifer types such as H and A, HKH, and HA and KH. The VES results correlated with lineament intersection density in terms of groundwater occurrence. The research has been able to justify the significance of lineament intersection density as a means of providing potable water, through the drilling of boreholes and well water. The general observation made in this research from the remote sensing and aeromagnetic dataset in groundwater studies is not only limited to the generation of hydrogeological maps alone but the intersection of detailed geological lineament from both surface and subsurface geological structures, which will give better information in terms of groundwater accumulation and abstraction.