الفهرس 
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Abstract
The present work deals with the study of the stratigraphy, systematic paleontology, paleoecology, ichnology and the microfacies studies of the exposed Eocene rocks at Nile-Fayum Divide. Two sections representing Qasr El-Sagha Formation of Late Eocene age were collected and photographed for this study. The first section represents Temple Member (section A) and the second section represents Dir Abu Lifa Member (section B). Stratigraphically, Temple Member consists of repeated cycles of fine marly sandstone, gypsiferous marl, sandy shale, and carbonaceous mudstone. While Dir Abu Lifa Member consists of cross bedded sandstone with plant root traces overlain by a highly fossiliferous argillaceous limestone and gypsiferous claystone with large burrows in different orientations. The paleontologic study revealed thirteen species (three gastropods, six oysters and four Carolias). The paleobiogeography of the studied fauna indicates that Ostrea (Turkostrea) multicostata (Deshayes, 1832) appeared in the Paleocene of Tunis and Algeria and spread in the Lower Eocene to North Africa, north-western Europe and India and persisted in North Africa during the Middle Eocene and disappeared from Europe. It also shows that genus Carolia was first recorded from the Lower Eocene of Egypt and Indian-Pakistani Region and its last occurrence was in the Early Miocene of North America. The statistical study on genus Carolia indicates that the distance between the byssal muscle scar and the retractor muscle scar increases with the convexity of the left valve. The paleoecologic study of the macrofaunal groups shows that the favorable environmental conditions caused their abundance in the lagoonal environment, however, the extinction of genus Carolia at the end of Late Eocene was a result of stress environmental factors, predation and parasitic elements during their life which has a great influence to cause their extinction. The study also reveals six Ichnogenera, Thalassinoides Ehrenberg, 1944; Ophiomorpha Lundgren (1891); Skolithos Haldemann (1840); Diplocraterion Torell, 1870; Arenicolites Salter, 1857 and Planolites Nicholson, 1873.These Ichnogenera are related to Skolithos Ichnofacies of typical sandy shoreline environment, but only the ichnogenus Planolites is related to Cruziana Ichnofacies, which occurs in somewhat deeper water than the Skolithos Ichnofacies. Trypanites ichnofacies are associated with hardgrounds associated with Carolia and oyster banks in the studied sections.The microfacies and the depositional environment interpretation were interpreted through the investigation of thirty thin sections. The examination of these thin sections indicates that they can be categorized into Clastic group (90%) and Carbonate group (10%). The clastic group includes Siltstone and Shale/Claystone Facies, Ferruginous Fossiliferous Sandstone and Carolia Bioclastic Glauconitic Calcareous Sandstone Facies Type. The carbonate group includes Sandy Ferruginous Dolomitic Bioclastic Packstone Facies Type.