A Preliminary Assessment of the Groundwater Potential of Ekiti State, Southwestern Nigeria, using Terrain and Satellite Imagery Analyses.

Abstract

A preliminary investigation involving the interpretation and analyses of hydrogeomorphological and remote sensing data had been carried out in the Basement Complex terrain of Ekiti State, Southwestern Nigeria. This was with a view to assessing the groundwater potential of the state.  The Topographic map and Landsat Mapper (TM) satellite imagery (1986) of the study area were acquired and processed using the ArcGIS and ERDAS Imagine Software. The hydrogeomorphological, lineament density and lineament intersection density maps were generated from the processed remote sensing data. Hydrogeomorphological, lineament density and lineament intersection density maps were integrated for the classification of the study area into different groundwater potential zones. Five hydrogeomorphological units including hills/ridges, pediments, pediplains, pediplain with alluvium, and valleys were delineated in the study area. The lineament map showed that the linear structures in the study area generally trend along N-S, ENE-WSW, E-W and NW-SE directions. The lineament intersection nodes dominated the northwestern, western and south-eastern parts of the study area. Both the hydro-significant lineament and lineament intersection density maps revealed five (5) lineament cluster zones. Based on the foregoing, the study area was characterized into five different groundwater potential zones which are very low, low, moderate, high and very high groundwater potential zones.

Keywords: Basement Complex, Geomorphology, Lineament, Lineament Density, Groundwater Potential, Ekiti State.