الفهرس 
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Abstract
The questions which may arise now are: 1 why the cretaceous was chosen for this study and 2 why the focus on rocks belonging to the duwi formation at the Egyptian eastern desert in particular that first the cretaceous is considered as a turning point in the life history eg. cretaceous witnessed the roots of modern grasses placental mammals and calcareous planktons and the evolution and thenextinction of great repiles second cretaceous time was so significant in the earth’s geological history being corresponded by noticeably high temperatures and extensive marine transgressions producing a rock mass accounting for about 22 of the Phanerozoic sedimentary mass Mackenzie 1990.