GEOCHEMISTRY OF THE MIOCENE SANDSTONE AND SHALE AT UM GREIFAT AREA, CENTRAL EASTERN DESERT, EGYPT: IMPLICATIONS TO PROVENANCE, TECTONIC SETTING AND RARE EARTH ELEMENTS POTENTIALITY

The studied Miocene sandstone and shale rocks are belonging to El-Ranga Formation. Petrographically, the sampled sandstone is classified as sublitharenite with evidence on variable transportation distances and derivation from sedimentary, igneous and/or metamorphic rocks. The iron oxides appear as the dominant cementation while quartz is the main matrix material in this sandstone. On the other hand, the shale appears as silty-to sandy shale consisting of fine to very fine, subangular to angular and moderate to poor sorted grains. Mutual bands of the black manganese oxides and brownish-yellow iron oxides are sometimes observed with indication of silica-rich solutions post-dated the formation of these bands.