الفهرس 
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Abstract
The Upper Cretaceous-Lower Paleogene successions exposed between Sibaiya City in the south and central Wadi Qena area to the north, between Latitudes 25°00’ to 27°30’ N and Longitudes 32° 10’ to 33° 00’ E in the Eastern Desert, Upper Egypt have been studied to achieve a high-resolution sequence stratigraphic framework as well as to throw more light on the sedimentary history of the region. In order to realize the objectives of this study; detailed field observations, sedimentological and biostratigraphical analyses were considered by measuring four detailed stratigraphic sections covering the studied sequence from the south to the north; Gabal Oweina, El-Hanadi, Gabal Qreiya and Timimit el Shifa sections. Lithostratigraphically, the studied sequence has been subdivided into seven rock units from base to top; Quseir, Duwi, Sudr, Dakhla, Tarawan, Esna and Thebes formations which were discussed in detail. Based on the similarity of the lithology, facies composition and according to the priority of the stratigraphic nomenclature code, some of the previously used rock unit names by other authors were redefined and amended. Biostratigraphically, twenty-three planktonic foraminiferal zones were identified covering the interval from Late Cretaceous (Campanian) to Early Eocene (Ypresian) age, which helped in determined the age of different rock units as well as the possible missing time periods (hiatuses). As well, twelve distinctive benthonic foraminiferal assemblages have been recognized for the use of paleobathymetry, ranging from the inner neritic to the middle bathyal paleodepths. To conduct the sedimentological investigations, about 220 microscopic thin sections representing the different rock types in the studied area have been carefully examined petrographically. Twenty-four microfacies association types were recorded, helped in identifying the different sedimentary environments that ranging from the marginal environment, shallow subtidal shelf environment and deep subtidal shelf environment. Many types of diagenetic processes including compaction, cementation, recrystallization (neomorphism), and dolomitization have been taking into consideration. In addition, two types of meter-scale cycles; shallowing upward cycles and deepening upward cycles; have been recorded. The above summarized field observations as well as the sedimentological and biostratigraphical analyses enabled to achieve the sequence stratigraphic framework of the Upper Cretaceous-Lower Paleogene successions in the studied area. Six third-order depositional sequences with their surfaces and systems tracts are recognized. It is clear that there is a substantial parallelism of the shallowing and deepening episodes from the comparison of the sea level curves of the studied area with the global eustatic sea-level curve (Haq et al., 1988) during the studied Upper Cretaceous-Lower Paleogene successions. Most of the sequence boundaries coincide with the global sea-level curve indicating that the global eustasy was primarily responsible for their development. In addition, some of these boundaries indicate the effect of local tectonics, which was also an important control on sedimentation. Consequently, the evolution of the studied Upper Cretaceous-Lower Paleogene sedimentary basin in the Eastern Desert of Egypt has been controlled by both the relative changes in sea level with the local synsedimentary tectonics. It is believed that the impact of collisions between the African/Arabian and Eurasia plates in these times played a major role in the evolution of the sedimentary basin under study.