الفهرس 
LithostratigraphyOnly 14 pages are availabe for public view
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Abstract
Stratigraphical and paleontological studies on the Middle and Upper Eocene sediments of Gebel Mokattam,East of Cairoland Gebel Mishgigah, Western Fayoum, have been carried out to shed some light on: 1- The litho-and biostratigraphy of the successions 2- Microfacial types of the rocks 3- The paleoecology and the depositional environments of the sediments. 4- The systematic paleontology of four faunal and floral groups. Lithostratigraphically, Gebel Mokattam section is composed of two Formations: 1) Mokattam Formation The entire formation is composed of Limestone and marly limestone. It is divided into four rock units,from base to top: A- White Limestone Member (28 m. thick) White, hard, fragmented limestone enriched by Pelecypoda, Gastropoda shell and smaller N u ~ m u Z i t e s spp. such as NwmnuZites praediscorbinus. This Member is of Lower Lutetian age (Middle Eocene). B- Gizehensis Member (30 m. thick ) It is creamish white, detrital, packed, hard limestone enriched by Nummulites gizehensis together with some Pelec~poda, Gastropoda shell and echinoid fragments. This Member is of Middle Lutetian age (Middle Eocene). C- Building Stone Member (50-70 m. thick ) Yellowish white, massive, hard, fine grained limestone, interclated irregularly by thin yellowish white marl. It contains abundant Nautilus Sp. at the base. his Member is of lower Upper Lutetian age (Middle Eocene). D- Giushi Member (50 m. thick ) It is underlies the Maadi Formation and. represented by hard, yellowish white limestone, intercalated regularly by thin layer of marls (30-50 cm). This member is previously known as ”Bryozoa Limestone”. It is of Upper Lutetian age (Middle Eocene). This Member ends by compact, hard, white limestone fossiliferous( = ”Operculina bed” by some authors). It attains thickness about 2 m. and it is enriched by Nummulites aff pulcheZZus. 2) Maadi Formation It is overlies the Giushi Member and underlies the Oligocene Gebel Ahmer sand and gravels. This Formation starts with a group of soft greyish yellow, limy marl and claystone beds, intercalated by a relatively thinner shale and gypsum ( = Tafla bed),followed by sandy limestone shell beds dolostones and ends by echinoid sandydolomitic limestone. This Formation belongs to Upper Eocene age except the most lower part (5 m.) of this formation which is belongs to Bartonian age (Middle Eocene). Gebel Mishgigah section is considered as a Member of the Wadi Rayan Formation. It overlies El Masakheet Member and underlies the Gehannam Shale Member of ~ehannam Formation (ISMAIL and ABDEL-KIREEM, 1 9 7 1 ) - On the other hand, It overlies the Muweilih Member and underlies the Medawarah Formation (SHAMAH, 1981). The bulk of the Mishgigah section generally composed of sandy limestone with abundant NummuZites SPR,limestone, chalky limestone, dolostone and marls. P a l e o n t o l o g i c a l l y f o u r t y p e s of m i c r o f o s s i l s h a v e s t u d - i e d , t h r o u g h two s e c t i o n s a r e F o r a m i n i f e r a , O s t r a c o d a , Bryozoa and c a l c a r e o u s n a n n o p l a n k t o n . Based on t h e s e m i c r o - f o s s i l s t h e f o l l o w i n g b i o z o n e s a r e r e c o g n i z e d : A) Nannofloral Zonation. F o r t h e f i r s t time t h e t y p e s e c t i o n of t h e M i d d l e and Upper E o c e n e i n E g y p t , G e b e l Mokattam h a s been s u b d i v i - ded on t h e b a s e s of c a l c a r e o u s n a n n o p l a n k t o n . S i x b i o z o n e s b a s e d on 45 s p e c i e s , a r e r e c o g n i z e d and d e s c r i b e d . They a r e from b a s e t o t o p 6. E r i c s o n i a s u b d i s t i c h a 5. I s t h m o Z i t h u s r e c u r v u s 4. C h i a s m o Z i t h u s o a m a r u e n s i s Zone P r i a b o n i a n Maadi Fm. Zone Zone B a r t o n i a n 3. D i s c o a s t e r s a i p a n e n s i s Zone Mokattam F m. 2. R e t i c u l o f e n e s t r a u m b i l i c a Zone L u t e t i a n 1. D i s c o a s t e r s u b l o d o e n s i s Zone The a b s e n c e o f t h e N a n n o t e t h n a f u l g e n s Zone , which i s r e c o r d e d i n Abu Zeniema a r e a , S i n a i by KERDANYetaZ. ( 1 9 8 0 ) b e t w e e n t h e D i s c o a s t e r s u b Z o d o e n s i s Zone and t h e ReticuZofenestra wnbiZica Zone i n t h e Mokattam s e c t i o n may be d u e t o a n o n d e p o s i t i o n r a t h e r t h a n non e x i s t e n c e . The p r e s e n c e of D i s c o a s t e r subZod o e n s is Zone i n t h e W h i t e L i m e s t o n e Member of t h e Mokattam F o r m a t i o n i s e v i d e n c e f o r t h e e x i s t e - n c e of t h e Lower L u t e t i a n b e d s . The a p p e a r a n c e of C h i a s m o l - i t h u s o a m a r u e n s i s Zone is c o n s i d e r e d a s t h e t o p m o s t of t h e M i d d l e E o c e n e ( B a r t o n i a n ) . I n G e b e l M i s h g i g a h only o n e C a l c a r e o u s n a n n o p l a n k t o n zone i s r e c o g n i z e d , i t is R e t i c u Z o f e n e s t r a u m b i Z i c a Z o n e , t h a t i s d i v i d e d i n t o two s u b z o n e s a s f o l l o w s : Discoaster saipanensis subzone Lutetian CycZicargoZithus reticuzatus subzone