Document Type

Original Article

Subject Areas

Earth science


Duwi; Egypt; Nile Valley; Phosphorite; Uranium


The present study deals with geological, mineralogical and geochemical studies of the Upper Cretaceous Duwi Formation bearing phosphorites and its radioactivity at east Mahameid area, Nile Valley, Egypt. In the studied area, 100 boreholes were drilled in three sectors; Abu Sabona (A); Araby (B); and EI- Mallaha (C). The selected core samples have been described to illustrate the stratigraphic succession of the investigated area. Thirty phosphorite samples were studies petrographically and analyzed chemically. The chemical analyses carried out at the Labs of Nuclear Materials Authority (NMA). The obtained data revealed the formation of the Lower Phosphorite Member as isolated lenticular bodies. The Lower Phosphorites Member is deposited in shallower epicontenental marine environment than the upper one. The abnormal concentration of Cr, Ni favor their ultramafic –mafic source rock. The slight difference in cU and eU with increasing in cU contents in most samples relative to eU, could be connected to recent uranium migration from the upper black shale of the Dakhla Formation.

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