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Abstract The forminiferal contents of three surface sections from south to north(Gebel Tarboul,Wadi Tarfa,and Bir Dakhl sections) in southern Galala sub-basin,North Eastern Desert, Egypt had been studied in detail and used in biostratigraphy and chronostratigraphy bof the Upper Cretaceous-paleogene successionsThe foraminiferal contents of three surface sections from south to north (Gebel Tarboul, Wadi Tarfa, and Bir Dakhl sections) in Southern Galala Sub-basin, North Eastern Desert, Egypt had been studied in detail and used in biostratigraphy and chronostratigraphy of the Upper Cretaceous – Paleogene successions. Sixty-nine planktonic foraminiferal species belonging to twenty-three genera have yielded 13 biozones and 6sub-biozones. They are, in ascending order: Globotruncana aegyptiaca IZ, Gansserina gansseri IZ, Contusotruncana contuse - Racemiguembelina fructicosa IZ, Abathomphalus mayaroensis IZ, Globanomalina compressa/Praemurica inconstans LOSz (P1c), Praemurica uncinata LOZ (P2), Morozovella angulata- Globanomalina pseudomenardii IZ (P3), Igorina pusilla PRSz (P3a), Igorina albeari LOSz (P3b), Globanomalina pseudomenardii TRZ (P4), Globanomalina pseudomenardii/Parasubbotina variospira CRSz (P4a), Acarinina subsphaerica PRSz (P4b), Acarinina soldadoensis/Globanomalina pseudomenardii CRSz (P4c), Morozovella velascoensis PRZ (P5), Acarinina sibaiyaensis LOZ (E1), Pseudohastigerina wilcoxensis/Morozovella velascoensis CRZ (E2), Morozovella marginodentata PRZ (E3), Morozovella formosa LOZ (E4), and Morozovella aragonensis/Morozovella subbotinae CRZ (E5). The analysis of quantitative and qualitative distribution patterns of benthic foraminifera complement with the recognition of eight mixed clastic-carbonate facies types (MF-1 to MF-8) of the upper Cretaceous –lower Paleogene succession are suggested that the depositional environment range from an outer neritic to bathyal. Based on sequence stratigraphic analyses, ten complete 3rd order depositional sequences each bounded by sequence boundary, are recognized. Moreover, Local and widespread regional (from previous studies) hiatus was detected in the pelagic to hemipelagic sequence during Cretaceous-Paleogene succession in Southern Galala Sub-basin. This hiatus corresponds to the Early Maastrichtian-Early Eocene in Gebel Tarboul (with missing whole Paleocene period), the interval between Late Maastrichtian-Early Paleocene throughout Wadi Tarfa sequences, and Late Maastrichtian-Late Paleocene in Bir Dakhl section. Local normal faults influenced the depositional architecture of the Upper Cretaceous–Paleogene strata in Southern Galala Sub-basin. A major change in faultrelated movements and basin depocenters and thus creation of two accommodation zones in the shoulders of the basin toward the north and south, result in hanging walls subsidence through the Cretaceous after the initial rifting stage of the Syrian Arc System (and relative sea-level rise) synchronous with footwall uplift and a relative sea-level fall. As sediments initially load, an anomalously thick siliciclastic-carbonate sedimentarypackage builds up on the subsiding blocks of the faults zone and become progressively thinner in the center of the basin. During the reverse reactivation of these faults in the Middle-Late Paleocene, a localized uplift has occurred in Gebel Tarboul and Bir Dakhl synchronous with relative sea-level drop. Consequently, the Late Maastrichtian-Early Paleocene sediments were removed due to Late Paleocene erosion which led finally to theI hereby declare that research work titled “Stratigraphy and facies analysis of Late Cretaceous-Early Tertiary sequences, North Eastern Desert, Egypt” is my independently work and without using unauthorized aids. where material has been used from other sources it has been properly acknowledged / referred. Neither this nor a similar work has been presented elsewhere for assessment, published or submitted for publication. unconformable contact between formationsThroughout the Earth’s history a number of events have occurred on different timescales, driven by a multitude of forcing mechanisms and affecting the depositional system and basinfilling processes. These events include: Climatic change events: global warm (9-10ºC rise in high latitude Sea Surface Temperature; 4-5ºC rise in deep sea and equatorial Sea Surface Temperature; and 5ºC rise on land) during Paleocene Eocene Thermal Maximum (PETM) (Hanif, 2011); Biotic events: deep sea Benthic foraminiferal extinction (Benthic Extinction Event (BEE) across the PETM which characterize by Ecosystem variations); global mass extinction, an estimated 75% of creatures, occurred across the Cretaceous-Paleogene Boundary (65-66 m.y);Tectonic events: tectonic processes working on scale of several million years (Volcanism, plate tectonic and its related structures like Syrian arc system, uplifting , or subsidence), orbitallly induced changes in the amount of solar radiation that reaches the Earth on the scale of Milankovitch cycles (~18 - 400 kyr) or on even shorter timescales (Ruddiman, 2001).Egypt forms the north-eastern part of the African continent and is situated between latitudes 22° and 31° north. The country covers an area of about one million km2 and occupies nearly one-thirtieth of the total area of Africa. The largest part of Egypt consists of desert, the so called Western Desert, to the west of the Nile, the Eastern Desert, east of the Nile Valley and the Sinai Peninsula, delineating the north-eastern extension of the SaharaIn the studied Southern Galala Sub-basin, on the northern part of Egyptian territory where the unstable shelf located, marine sedimentary sections across the Cretaceous/Paleogene (K/Pg) interval are widely distributed and preserved in the Sudr, Dakhla, Tarawan and Esna formations. Several authors have studied the stratigraphy, biostratigraphy and sedimentology of the outcropping Cretaceous–Paleogene succession in the Eastern Desert of Egypt (e.g. Hume, 1911; Awad and Abdallah, 1966; Abdel Kireem and Abdou, 1979; Bandel and Kuss, 1987; Bandel et al., 1987; Hendriks et al., 1987; Kuss and Leppig, 1989; Kuss et al., 2000, Ismail et al., 2009; Scheibner and Speijer, 2009; Höntzsch 2011; Ismail, 2012 and Hefny et al., in press)During the early Late Cretaceous, Egypt was situated at the southern margin of the Neotethys at ca. 5º northern paleo-latitude (Philip and Floquet 2000). The Cretaceous-Paleogene rocks are well exposed in the northern part of the Eastern Desert. However, outcrops of lower Upper Cretaceous (Cenomanian-Turonian) strata are comparatively rare and little is known in detail about their facies and depositional environment. The Campanian-Eocene interval was probably the most widespread sediments in Eastern Desert, formed during a major transgressive period when the sea extended up to some 1000 km inland of the present coast (Picard, 1943; Said, 1962; Garfunkel and Bartov, 1977).The investigated area represents a segment of the northern passive margin of the Afro- Arabian plate, formed during the Late Triassic-Jurassic opening of the Neotethys. The extensional tectonic processes resulted in the formation of eastwest- striking northwarddeepening half-grabens that were mostly covered by the Late Triassic-Early Cretaceous seas, depending on, among others, sea level fluctuations (Scheibner et al., 2001). Beginning with the initial stages of the collision between the African and European plates during Turonian times, a dextral transpressive reactivation of the half-grabens took place along the North African-Arabian plate boundary (e.g. Aal and Lelek 1994, Moustafa and Khalil, 1995). As a consequence, a system of inverted, uplifted and folded grabens was formed, called the Syrian Arc System & ‘unstable shelf’ (Krenkel, 1925, Said, 1962). These structures were mainly active during the Late Santonian (Kuss et al. 2000; Rosenthal et al. 2000). But there is evidence of several Early Eocene tectonic pulses on the same structures in the Galala Mountains that recently discussed in details by Höntzsch et al. (2011). The Galala Mountains in the Eastern Desert, together with areas in western Sinai, represent a southern branch of the Syrian Arc called the Northern Galala/Wadi Araba High (NGWA) (Kuss et al., 2000), characterized by Late Cretaceous uplift in the north and subsidence further to the south |