A protracted phase of aggradation without evidence for episodes of cutting and filling occurred in the drainage of Wadi el Sheikh between about 65,000 and 12,000 BP. Marl sediments in the deposits at the oasis of Tarfat el Quidrein denote freshwater ponds or marshes that attracted Upper Palaeolithic, Ahmarian hunter-gatherers. Wetter conditions favoring the formation of the marls are explained by local, geomorphic factors including the orographic influence of nearby mountains. A major phase of down-cutting initiated at the end of the Pleistocene and beginning of the Holocene is the only climatically forced gradational change seen in the geomorphic record.