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Palynological investigations of samples collected from the Abu Roash Formation, Faghur Hj5-1 well, north Western Desert, Egypt show a low diversity in palynomorph assemblage. This assemblage is mainly dominated by a clear proliferation of Pediastrum (and other allied algal forms, e.g., Scenedesmus and Botryococcus) which today lives exclusively in freshwater. Such a prominent record within the current marine deposits could be considered a good biostratigraphic datum in the Upper Cretaceous (Turonian) period rather than an ecologic event in the north Western Desert, Egypt. The influence of freshwater input on the studied deposits is proven by the presence of heavy minerals including kyanite, zircon, staurolite, and amphiboles encountered in siliciclastic sediments. Most of these minerals are sub-rounded to rounded so they were derived probably from sedimentary rocks. In the studied succession, the presence of Pediastrum reflects sea level fall (i.e., lowstand systems tracts). The occurrence of Pediastrum and other algae in such marine deposits reflects the predominant deposition of fluviatile sediments related to the discharge of rivers into shelf seas.