Contribution To The Sedimentology Of The Bahariya Formation Of Gebel El-Dist, Bahariya Oasis, Western Desert, Egypt

Abstract

Combined microscopic, grain-size and heavy-mineral analyses were carried out on the Bahariya Formation at Gebel El-Dist (type section), Bahariya Oasis. These studies revealed that the formation is composed of moderately poorly-sorted silty sandstones and sandy siltstones with few intercalations of sandstones, siltstones and clayey siltstones. The heavy-mineral suite is composed of (in order of decreasing abundance): opaques, zircon, rutile. staurolite, tourmaline, kyanite, garnet and biotite. Seven heavy-mineral zones are delineated in the El-Dist section. Comparison of these zones with those recognized in another occurrence of the Bahariya Formation revealed that they have a wide areal distribution. The Bahariya Formation was deposited mainly in fluviatile and deltaic environments, with low energy. The sediments were inherited from an igneous rock with minor contribution from metamorphic and sedimentary lithologies. The provenance remained almost unchanged during the deposition of the formation.