Geological and Mineralogical Studies of Uraniferous Microgranites from Ras Abda Area, North Eastern Desert, Egypt

Abstract The current study investigates the geology and mineralogy of uraniferous microgranites from Ras Abda area, northeastern Desert, Egypt. The Precambrian basement suites of the studied area comprise older granitoids, microgranite dykes, and post granitic dykes and veins. The microgranite dykes occur as swarms and vary in color from buff and pink to dark red and brown. They are confined to a highly deformed, faulted, and sheared narrow zone, that is more than 1500m long in NE to NNE direction and up to 300 m in width. Several hydrothermal alteration processes, including hematitization, silicification and kaolinitization have varying degrees of impact on the rock. The radioactive mineralizations in the studied area are: (a) uranium minerals (kasolite and uranophane), and b) thorium minerals (thorite, uranothorite and orangite). Occasionally, secondary uranium minerals are found filling micro-fractures or coating joint surfaces.