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Paleozoic rocks in the Wadi El Sahu area are affected by many major faults in different directions. A reverse fault trending NE‐SW is exposed for about 300 m of its length as it cuts through the Abu Hamata and Adedia formations on the south side of Wadi El Sahu. A secondary ascending hydrothermal solution carrying heavy metals and radioactive minerals passed through the fault plain and the surrounding fractures, forming mineralized and radioactive zone. The mineralized zone thickness ranges from 60 cm to 200 cm along the fault plain. These rocks were analyzed radiometrically using a portable gamma‐ray spectrometer, chemically by employing ICP‐ES and ICP‐MS, as well as mineralogically by both binocular and Environmental Scanning Electron microscope. Gold content was also determined by fire assay. REE and U contents reached up to 2682 and 1216 ppm, respectively. Mineralogical investigations indicated the presence of uraninite, torbernite, autunite, sklodowskite, kasolite as uranium minerals, thorite as a thorium mineral, monazite, allanite and xenotime as REE‐bearing minerals, zircon and columbite as accessory minerals, gold and nickel as precious and base metals, in addition to cassiterite, chalcopyrite, chalcocite and chrysocolla. High REE and U contents are attributed to the circulation of epigenetic U and REE‐bearing hydrothermal solutions along the fault plain and its surrounding fractures. Hydrothermal alteration processes could then be confirmed by the presence of the M‐type tetrad effect in the REE‐patterns of the ferruginous sandstone. The non‐chondritic ratio of Nb/Ta, Zr/Hf and Y/Ho in the studied sandstone may be attributed to the tetrad effect. The Ce and Eu anomaly with unusual REE‐patterns was represented by the presence of conjugated M‐W tetrad effects, indicating either the dual effect of hydrothermal solutions or groundwater with seawater. The results clarify that the tetrad‐effects could be used as evidence for the environment of deposition and as an indication for gold mineralization.

Gabal Alloga area is located in the southwestern part of the Sinai Peninsula. It represents one of the more significant economic and uranium mineralized areas. It is located within a low basin and most of the high radioactive anomalies recorded in the sediments of Um Bogma Formation within this basin. The Lower Carboniferous Um Bogma Formation is the main rock units constituting the face wall of the Allouga quarry. The wall shows very high radioactivity with eU-contents reaches 3000 ppm. Sklodowskite and carnotite represent the main uranium minerals detected in the face wall of the quarry with anomalous contents of gold. The gold content reaches 1.78, 1.74, 2.02, 1.6, 1.78 and 1.8 ppm in the ferruginous sandstone, dolostone, black shale, marl, claystone and gibbsite, respectively. The structure (faulting), lithology (carbonaceous material and clay minerals in addition to iron oxides), topography (low basin) and biogenic effects (organic matter) are the main factors that controlled the localization and concentration of the uranium and gold minerals within the Um Bogma Formation in the G. Alloga area, especially in Alloga Quarry. In addition to the secondary ascending hydrothermal solutions carry out the radioactive and gold minerals to deposit mainly along with fractures and faults.

Ferruginous sandstone considered as a one of the economically significant uranium mineralized areas in the southwestern part of the Sinai that located at the lower member of Um Bogma Formation in Abu Thor area. The studied sample was characterized geologically as a sandstone rock contain 450 mg/kg of uranium. This work is aimed to compare between eco-friendly bioleaching and conventional leaching processe. The uranium bioleaching efficiency achieved 80% by using a native fungal strain; Aspergillus nidulans as a green technology with the optimimum conditions as; 3 pH value, 3% pulp density, 7 days incubation period, and 30 °C incubation temperatures. Whereas the traditional technique using alkaline and sulphuric acid leaching attained 68.5% and 95% respectively at the best condition. Finally, the shrinking core model was represented the layer diffusion process by acquiring apparent activation energy 18.28 and 16.82 kJ/mol for carbonate and sulphuric acid leaching, respectively.