الفهرس 
MethodologyOnly 14 pages are availabe for public view
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Abstract
Five Lower Tertiary successions were selected from the Central Nile Valley area at G. El-Sheikh Eisa (Qena area), G. El-Shaghab and G. El-Homra El-Shanka (Esna area) and G. Umel-Ghanayem and G. TeirITarawan (Kharga Oasis) to study their sedimentological and micropaleontologica1 characteristics. The data of granulometric analysis have shown that there is no marked variation between the grain size of the Dakhla and Esna Shales. Nearly all the studied sediments are made up of silts with generally small amounts of sands and clays. The hyperbolic shape of the cumulative curves suggests that these sediments were deposited from muddy contourites under the action of decantation. X-ray diffraction analysis of the argillaceous sediments revealed that the diagenetic kaolinite has dominated the Danian part of the Dakhla Shale whereas, detrital kaolinite is the comn~on constituent in the Thanetian part. Meanwhile, the Esna Shales are generally rich in well-crystallized smectite of most probably authigenic origin. Petrographic examination of the carbonate rocks encountered in the investigated successions revealed the presence of four microfacies associations: mudstone/wackestone, wackestone, wackstone/packstone and packstone facies. The carbonate-rich sediments have generally the lowest proportion of insoluble residue and highest proportions of CaC03. In contrast, argillaceous sediments especially, Esna Shales have the highest content of insoluble residue and lowest content of CaC03. However, the Dakhla Shales contain the highest values of organic carbon. The abundance of planktonic foraminifera and calcareous nannofossils throughout the studied sections has led to the recognition of eight planktonic foraminifera1 and eight calcareous nannofossil biozones spanning the Paleocene to Early Eocene time. The Early Tertiary stage boundaries are defined on the basis of micropaleontologica1 and sedimentological characteristics. The DanianIThanetian boundary is placed at the base of blot-oro~~elalnng dcrtu Zone at G. Umel-Ghanayem and at the upper part of NP4 nannofossil Zone at G. El-Shaghab and G. TeidTarawan sections. On the other hand, thc PaleoceneIEocene boundary is located at the extinction level of Mor-osovellu velclscoensis which coincides with the NP9/NPIO zonal boundary at G. El- Shaghab and G. El-Homra El-Shanka and pass through the upper part of NP9 zone at the other sections. Some variations in the sedimentological characteristics especially in the acid insoluble residue and in the CaC03 content were recorded across the two boundaries. The present data revealed that the sediments of Qena area are deposited under highly productive and relatively deeper conditions compared to the other two areas. The clay minerals have proved to be a good index for paleoclimatic conditions prevailed during the Early Tertiary time.