Integration of geologic and remote sensing studies for the discovery of uranium mineralization in some granite plutons, Eastern Desert, Egypt

الملخص EN

The main objective of this research is to integrate geology with remote sensing techniques to establish common characteristic features leading to the recognition of other uranium mineralizations within the Pan-African younger granites of the Eastern Desert of Egypt.

The associations of aplites, quartz and jasperoid veins and lamprophyric dykes as well as alteration processes throughout and near the mineralized sectors appear to play an important role in the distribution and localization of the mineralization.

Image processing techniques were applied on the digital subset ETM+ data covered the studied areas.

These techniques generated several products of enhanced satellite imagery, such as colour composite images, ratio images and principal component images.

These techniques have been successfully used in the lithological discrimination of uranium-bearing granites.

The capabilities of remote sensing data to characterize the uranium bearing granites, in addition to characterization and mapping the hydrothermal alteration zones usually helps in localization of uranium mineralizations.

Extensive field geologic and radiometric investigations to the pronounced zones delineated by the image processing technique, led to discovery of four locations of high radioactive anomalies with some uranium mineralizations, mainly connected to the studied younger granites.

Mineralogical studies were carried out, using ore and scanning microscope and XRD, for some selected mineralized samples.

These investigations confirm the presence of uranophane mineral as uranyl silicates.

The uranophane mineral is found in close association with hematite, quartz, calcite and chlorite.

Relics of corroded pyrite grainsare disseminated in the groundmass and filling some vugs and cavities.

The uranium mineralization is found adsorbed and enclosed around pyrite.

This may indicate that the presence of pyrite created a reduced environment favourable for the precipitation and fixation of uranium.