Radioactive mineralizations on granitic rocks and silica veins on shear zone of El-Missikat area, Central Eastern Desert, Egypt.

The shear zone of the El-Missikat area is considered one of the most important occurrences of uranium (U) mineralization in the Central Eastern Desert of Egypt. This shear zone is characterized by a tabular elongated zone of crushing and brecciation resulting from many parallel fractures or intense jointing, and presence of silicification and other alteration products together with the occasional presence of U mineralization. The concentrations of the natural radionuclides were measured by Sodium Iodide Detector NaI (Tl) in 87 granitic rocks and silica veins collected from the Central Eastern Desert. Measurement of radioactive elements suggests U present in granite of the El-Missikat pluton as well as in red, black and jasperoid silica veins. Radioactive mineralization was determined by scanning electron, binocular, and polarizing microscopies. The mineralizations are represented by syn-genetic U-leaching origin accompanying granitic rocks and post-magmatic association in red and black silica veins. The U-host mineralizations are mainly represented by radioactive minerals such as uranophane, kasolite, and U-bearing zircon.