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The present study deals with the Cenomanian–early Turonian ostracods in the southern Sinai, Egypt. The investigated sequence includes the Raha and Abu Qada formations. The Raha Formation consists of distinctive Cenomanian taxa such as Cytherella aegyptiensis, Veeniacythereis maghrebensis, V. jezzineensis, V. streblolophata streblolophata, Monoceratina trituberculata, and Glenocythere reticulata. Based on the ostracod species, four local biozones are recognized, including Veeniacythereis jezzineensis – Metacythereopteron berbericum, Cytherella eosulcata – Xestoleberis derorimensis, Amphicytherura ziregensis and Perissocytheridea istriana – Cythereis fahrioni. The paleobiogeography of the considered ostracods suggests that there are two bioprovinces, the first of which is the North African province and includes Egypt, Tunisia and Algeria. The second bioprovince represents the Middle East province and includes Lebanon, Oman and Iran. The strong resemblance between the two bioprovince indicates a relatively good communication along the margin of Southern Tethys during the Cenomanian and improved marine ostracod exchange.  相似文献   
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This study deals with the Middle Eocene ostracods from southeast Fayoum area, Egypt. To carry out this investigation, three outcrops are examined, Gebel Elwe El Breig, Gebel Sath El Hadid and Gebel Munqar El-Shinnara. This study is based on the Midawara Formation that consists mainly of fossiliferous limestone, marly limestone and clay. The studied ostracod assemblage includes thirty-one species and subspecies, belonging to twenty-three genera and seventeen families. The ostracod group belonging to Cytheroidea Baird, 1850 represents the most abundant group that reaches 81.99% in Munqar El-Shinnara section, 81.88% in Sath El Hadid section, and 61.12% in Elwe El Breig section. The structure of the investigated assemblages (abundance of ostracods, number of taxa, Fisher's alpha, Shannon index, and equitability) indicates deposition in an environment belonging to the neritic zone. Moreover, this study tries to use the multivariate analyses to distinguish the paleobiogeographic provinces in Tethyan region during the Middle Eocene. These analyses are applied on a matrix consists of some nominated Middle Eocene species from 13 countries. The results point to two distinctive provinces, Southern Tethys Province (Algeria, Tunisia, Libya, Egypt and Jordan) and the Northern Tethys Province (England, Germany, Spain, France, Belgium, Ukraine, Hungary and Turkey). The reasonable similarities between these provinces may reflect a possible connection between both sides of the Tethys during the Middle Eocene age.  相似文献   
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The timing of desertification of the Sahara Desert is poorly understood, with recent estimates indicating an onset of hyper-aridity during the Latest Miocene. Field work in Egypt in 2005 has led to the discovery of evidence that indicates that 11–10 Ma the Western Desert was covered in woodland. Fossiliferous cave breccia at Sheikh Abdallah, Western Desert, Egypt, has yielded a Late Miocene (11–10 Ma) microvertebrate fauna, which contains Galagidae, Microchiroptera, Macroscelididae, Soricidae, Erinaceidae, and Rodentia. The locality also yielded the remains of frogs, snakes, lizards, and birds. The fauna indicates a mean annual rainfall in excess of 500 mm and perhaps as much as 1,200 mm. This palaeoclimatic information is important because it reveals that the Sahara Desert, which is today the largest in the world, was either considerably smaller during the Late Miocene than it is today, or that it did not yet exist as a continuous hyper-arid belt right across the continent. This data accords with estimates of a Latest Miocene (8–7 Ma) increase in aridity in the Sahara. To cite this article: M. Pickford et al., C. R. Palevol 5 (2006).  相似文献   
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Recent work in the high desert west of the historic site of Abydos has revealed a number of technologies that date from the Middle Paleolithic through later periods. The earliest of these include both Nubian and classical Levallois technologies, which are abundant and demonstrate virtually all stages of production. Presumed later technologies include both large blade production technologies as well as more expedient reduction methods. Although results are still preliminary, the lack of significant taphonomic disturbance, the abundance of refits (including many discrete flintknapping episodes), and the high visibility of the archaeological remains make this an ideal area to reconstruct the techniques of lithic reduction in use.  相似文献   
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