The Pliocene- Quaternary Nile sediments, occurring at Wadi Qassab area, could be differentiated into four terraces and recent river islands. The lithologies of these sediments as well as their heavy mineral contents suggest five successive stages of evolution of the River Nile.
The older Nile sediments show a relative deficiency in pyroxenes, wheras the modern sediments show higher concentration of pyroxenes.
In most of these sediments epidotes tend to increase at the expense of pyroxenes. Clay minerals constitute the major part of the shale deposits. They are composed of mixtures of montmorillonite, kaolinite, illite and montmorillonite/illite. The older Nile sediments are most rich in illite relative to the other modern ones.