الفهرس 
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Abstract
The present work is carried out to study the geology, litho- and biostratigraphy, facies analysis, depositional environment and sequence stratigraphy of the Upper Cretaceous-Lower Paleogene sequence that are exposed in the west central Sinai at Wadi Raha, Sudr El Hetan and Wadi El Giddi.
The studied sequence is subdivided into four formations; from base to top, Wata, Themed, Sudr and Waseiyit. They are consisting essentially of limestones with rarely intercalated claystone and marl beds.
Five biostratigraphic zones have been defined in the studied interval; two planktonic foraminiferal zones and three benthic foraminiferal zones. The planktonic foraminiferal zones are Early Maastrichtian Globotruncana aegyptiaca Zone and Early Eocene Morozovella subbotinae Zone. The benthic foraminiferal zones are Coniacian-Santonian Discorbis minutus Zone, Late Maastrichtian Bolivinoides draco draco & Bolivina incrassata Zone and Nummulites spp. Zone. The biostratigraphic analyses indicate that deposition of the Upper Cretaceous-Lower Paleogene sequence was interrupted by erosion and/or non-deposition related to tectonic activity.
Eleven microfacies associations are recorded in the rock units. Nine constitute a limestone facies (mudstone, wackestone, wacke/packstone, packstone, pack/grainstone, grainstone, rudstone, floatstone, framestone), one constitutes a dolostone facies (lime- bioclastic dolostone) and one constitutes a clastic facies (calcareous claystone).
The sequence is divided into two main environmental belts as the shallow subtidal and deep subtidal belts. The shallow subtidal belt includes restricted shallow subtidal (Wata and Themed formations), shoals (Themed Formation) and open marine shallow subtidal environments (Wata, Themed, Sudr and Waseiyit formations) and the deep subtidal belt includes the open marine deep subtidal environment (Sudr and Waseiyit formations).
Four depositional sequences (SQ) bounded by three sequence boundaries (unconformities) were detected. They are the Lower to Middle Turonian TSQI, the Coniacian-Santonian CSSQII, the Maastrichtian MSQIII and the Lower Eocene ESQIV. The sequences are subdivided into seven cycles of 3rd order and four supercycles. These cycles are compared with the eustatic model published by Haq et al. (1987, 1988). The identified sequence boundaries are Intra middle Turonian/Coniacian (SB1), Santonian/Maastrichtian (SB2) and Maastrichtian/Early Eocene (SB3).
The radical facies changes, depositional setting, biostratigraphic analysis, depositional sequence, system tracts and sequence boundaries reflect the main role of the tectonic activity related to the Syrian Arc Fold System with slightly role of the global static sea level changes in the depositional regime characteristics of the Upper Cretaceous-Lower Paleogene sequence.