الفهرس 
ABSTRACT
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Abstract
The Golden Triangle sediments are located between the governorates of Qena and Red Sea. It is a territory of nearly nine billion square meters with resources well recognized since Pharaonic and Roman eras and is considered the second largest development project run by the Egyptian government after the Suez Canal.
It is worth mentioning here that, the student has previously studied in her master’s thesis (2018) a part of the Golden Triangle sediments (G. Duwi, W. Nakheil and Zug El-Bohar), therefore its findings were not included in the current study.
Extensive previous academic studies were achieved on the geology of Qena - Safaga and Quseir areas. These studies include stratigraphy, sedimentology, mineralogy, geochemistry and structural geology. On the other hand, the applied ones were conducted primarily on phosphorites, groundwater prospection and chemistry, evaluation and geotechnical studies of Upper Cretaceous-Paleogene siliciclastics. The studied sediments include: pre-rift sediments (Upper Cretaceous – Paleogene), rift sediments (Late Oligocene? – Pliocene), Quaternary and placer sediments.
The studied Upper Cretaceous–Paleogene sediments are well exposed at G. Qrieya, G. Duwi and Um El-Huweitat areas and are represented by mixed siliciclastics–phosphorites and carbonates. These sediments belong to the Quseir, Duwi, Dakhla, Tarawan, Esna and Thebes formations. Within these lithostratigraphic units, thirteen sedimentary facies are easily differentiated and described in some detail.
At G. Qreiya, the pre-rift sequence started with the Quseir Formation which measures about 44m thick and can be subdivided upwards into four sedimentary facies (FQ1-FQ4). Each of which has its distinctive characteristic features (lithology and primary sedimentary structures). At Um El-Huweitat, the basal part which is equivalent to FQ1 of G. Qreiya is missing. There, the Quseir Formation (FH2-FH4) measures about 28 m thick forming four coarsening upward cycles. It is obvious that, the cycle interval is thicker in G. Qreiya compared with that of Um El-Huweitat area. The change in the coarsening upward style could be attributed to some factors such as syn-sedimentary tectonism or climatic changes. Moreover, the repetition of coarsening upward cycles is more frequent at Um El-Huweitat compared to G. Qreiya.
The occurrence of fine-grained sandstone and siltstones in addition to the abundance of plant remains and bioturbation may indicate the deposition of the basal part of the Quseir Formation (FQ1) under fluviatile system. The coarsening upward cycles point to the accumulation of the Quseir Formation either at G. Qreiya or even at Um El-Huweitat under deltaic system regime. The coarsening upwards and the green papery siltstone facies at G. Qreiya (FQ2) replaced by the overlying sandstone-siltstone facies (FQ3) may suggest the deposition of FQ2 and FQ3 in deltaic environment. This is witnessed by the occurrence of benthonic and planktonic foraminifera (Ammobaculites species, Flabellammina chapmani, Miliammina onyeamensis, Gaudryina pusilla, Haplophragmoides calculus). However, the sandstone-siltstone facies (FQ3) may be deposited as prodelta set sediments. The presence of trough cross-stratified sandstone lenses which terminate the Quseir Formation sequence at G. Qreiya (FQ4) may indicate their deposition as interdistributary channel sediments.
At Um El-Huweitat, the lower scour surfaces, coarse-grained to gravelly grains, cross-bedding, as well as the flaser-beddings and mud drapes encountered in the Quseir Formation suggest deposition by tidal activities (tidal flat environments). The relative abundance of sandstone and siltstone preserved in the tidal flat sediments is controlled by the variation in the energy of the tidal currents and the sediments available for transportation. The occurrence of high bioturbation exists at the base of the phosphatic beds of the Quseir Formation (FQ3), G. Qreiya indicates a phase of oxic conditions in which organic activity was maximum.
The existence of glauconite in (FH2) at Um El-Huweitat may deposition under marine environment. Dwarfed agglutinated foraminifera are recorded for the first time on the toppart sequence of the Quseir Formation (FH4) at Um El-Huweitat area. At Um El-Huweitat (FH4), the existence of dwarfed nanofossils (Watznaueria barnesiae) indicate reducing depositional environment. The occurrence of smectite in the black shale samples (FH4) has revealed the deposition of the toppart of the Quseir Formation under shallow-marine environment.
The local lateral variation of the contact between Quseir and Duwi formations at G. Qreiya and Um El-Huweitat, for example, is related to the effect of syn-sedimentary tectonism prevailing during the Upper Cretaceous time. Moreover, the variation of stratigraphic situation of black shale benthic foraminifera between G. Qreiya and Um El-Huweitat may related to the same effect (syn-sedimentary tectonism).