الفهرس 
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Abstract
The present study deals with geologic, mineralogic and geochemical studies as well as gamma-ray spectrometric survey for uranium potential - phosphates of Duwi Formation at Gabal Abu Had environ which lies to the NE of Qena town and covers about 450 km².
The phosphate-bearing sediments (Duwi Formation) are exposed in the Abu Had area of Late Cretaceous and Early Tertiary age. It conformably overlies Qusseir Formation and underlies Dakhla Formation; this succession is capped with Tarawan, Esna and Thebes formations and eroded along wadis which are filled with Quaternary deposits. It is represented by three members where the lower member is composed of yellowish brown phosphate bands with thin blackish shale with an average 2 m thick. The middle member is composed of grey to black, papery shale, cross-bedded siltstone, marl, oyster bank and thin phosphate layers, its maximum thickness in the study area approximately 57 m. The upper member is composed of yellowish brown phosphate at the weathered exposed surface with dolomitic lenses, black shale and capped with fossiliferous limestone bed; it ranges between 5.2 - 5.5 m with an average thickness of 5.35 m.
Petrographic studies of phosphate samples showed that it composed of phosphate particles include mudclasts represented by peloids (collophane grains), bioclasts (bone and teeth fragments), beside non phosphate particles of quartz, calcite and pyrite embedded in silica or calcite cements.
The XRD data of the phosphate samples recorded presence of hydroxyl apatite as the principal phosphate mineral. The identified non-phosphate minerals are calcite, quartz, gypsum, anhydrite and dolomite.