Mineralogy, Geochemistry and Alteration Characteristics of the Radioactive Granite at Wadi El Reddah Area, North Eastern Desert, Egypt

Abstract

Ground radiometric survey in Wadi El Reddah area, which represents the north eastern parts of Gabal Gattar batholith in the North Eastern Desert of Egypt, clearly distinguishes two anomalous bodies in the hydrothermally altered alkali feldspar granite. Localized uranium mineralization, formed predominantly of kasolite, is associated with zircon, fluorite, and cotunnite, accompanied by intense hematitization, desilicification, chloritization and K-metasomatism of the original host granite. The geochemical data showing that the mean U (174 ppm) in the mineralized domain is increased in abundances relative to the less altered granite. Mean Th (43 ppm), on the other hand, is relatively remains constant and mean Th/U ratios changes from 2.6 in the less altered granite to 0.27 in the mineralized zones. During mineralization processes, most of major and trace elements are mobilized to some extent where elements such as K, Rb, Zr, Zn and Pb are enriched, while Si, Sr and REE are depleted. The formation of secondary uranium mineralization are generally attributed to wet climatic episodes prevailed at the late Quaternary in Egypt.