Drainage basin morphology and terrain analysis of the lower Benue River Basin, Nigeria

Abstract

The Lower Benue Trough is part of the Benue Trough of Nigeria and it consists of a series of rift basins which form a part of the Central West African Rift System of the Niger, Chad, Cameroon and Sudan Basement fragmentations. This research attempts to evaluate the geomorphological changes on the drainage basin interpreted using several techniques including the use of Remote Sensing and GIS. Several digital image enhancement techniques such as general contrast stretching and edge enhancement were applied to the Landsat image in ARCGIS, after which structures were mapped out on-screen using ArcGIS. The Digital Elevation Model (DEM) of the Trough was also generated from Shuttle RADAR Topographic Mission and used to enhance geomorphic features. The analysis carried out on the images revealed that the slope tool calculates the maximum rate of changes between each cell and its neighbors. The drainage density calculated shows that the drainage area = 86282.1km², while the drainage density is 0.39872 km/km^-2. The result from the modeling concludes by revealing four sub-basins in the Lower Benue Trough with maximum thickness of 7-10km.

Keywords: Benue, Remote Sensing, GIS, Geomorphology, River Basin