Analysis of Geological and Geophysical Datasets for Radioelement Exploration in Kab Amiri Area, Central Eastern Desert, Egypt

Detailed geological mapping description of the different granitic types of Kab Amiri pluton were integrated with geophysical (ground gamma ray spectrometry and aeromagnetic) data to identify and map the distribution of radioelement concentrations as well as delineate structural trends that control the mineralized zones in the study area. The geologic studies revealed the existence of four granite varieties namely; biotite granite, garnet two mica granite, muscovite granite, and episyenite. The structural interpretation of geological and geophysical data revealed two intersecting sets of NW and NE-trending faults. The NW-trending set of faults is younger than the NE-trending set where the latter is dissected and displaced by the former. Interpretations of radiometric data revealed the presence of radioactive anomalies southwards that indicate an original increase in uranium contents in the same direction. It could be related to the prevailing NE and ENE fault trends. The southern anomalous zone is related to a very high episyenitization and uranium mobilization. It exhibits a sharp increase in the eU concentrations reaching 370 ppm resulting in a high eU/eTh ratio, approaching 4.5 and, characterized by oval shape trending in the NE direction. Some areas along the peripheral part of Kab Amiri pluton are episyenitized and show a remobilization of uranium. These areas are mostly controlled by faults mainly trending ENE. In the case of the episyenite zone, strong mobilization of uranium is expected to host epigenetic uranium occurrences because more uranium is available. It is obvious that the episyenite rocks of high permeability have higher levels of uranium and their ratios. Thus, these rocks act as an important reservoir for Umineralization bearing solutions.