Molybdenum-uranium-fluorite mineralization related to plutonism in the Gebel Gattar area, Eastern Desert, Egypt

摘要

Molybdenum and uranium-fluorite mineralizations in the Gebel Gattar area are hosted in potash -feldspar-rich muscovite granite. The U-F mineralization is concentrated in deformed and hydrothermal altered red granite. Uranium (and thorium)-bearing minerals comprise polycrase, uranopolycrase, uranpyro-chlore and liandratite. These minerals are closely associated with fluorite and zircon. Molybdenum is hosted in quartz veins intersecting the host granite. Molybdenite, native bismuth, galena, chalcopyrite, sphalerite, ai-kinite, berryite and native silver are identified. From fluid inclusions in fluorite and quartz temperature and composition of the mineralizing Mo and U-F-fluids between 220-106°C and low- to moderate salinity from 0 to 10 wt% NaCl_(eq) could be determined. The Mo and U-F mineralizations are genetically related with the concentrated late stage fluids of the granite intrusion.