569 THERMAL MATURITY EVALUATION AND HYDROCARBON etc ..... ben of Neogene age that crosses diagonally the Mesozoic-Paleogene structures of north- east Egypt. The graben is constrained by the major NNE-trending boundary “Clysmic” faults and longitudinally segmented by two transform systems. The basin appears as a simple, narrow, elongated trough dominated INTRODUCTION The Gulf of Suez Basin extends NNW of the Red Sea for 320 km and is 50-90 km wide between the Red Sea Hills and the mountains of Sinai (Figure 1). The basin covers an area of about 23 000 km 2 (Sestini 1995). The Gulf of Suez is a complex elongated rift-type gra- THERMAL MATURITY EVALUATION AND HYDROCARBON GENERATION OF CARBONATE ORGANIC RICH INTERVALS OF SUDR FORMATION, SHOAB ALI OILFIELD, GULF OF SUEZ, EGYPT Amal Othman, M. Awad Ahmed a , I. Korrat, and M. R. Sherief, Geology Department, Faculty of Science, Mansoura University 35516 Mansoura, EGYPT a Author for correspondence, email: ahmed5@mans.edu.eg ABSTRACT The occurrence of hydrocarbons is closely linked to the tectono-stratigraphic history of the Shoab Ali Oilfield, which has created multiple reservoir and seal combinations. The comprehen- sive integration of the geo-related data and the interpretation of the well logging, geochemical and the results of a well calibrated 1D model explain the different hydrocarbon distribution in the Shoab Ali Oilfield. The Sudr Formation of the Upper Senonian has high organic carbon con- tent and the capacity to generate petroleum liquids. The simulations for four wells in the study area show differences in burial, thermal history and maturity and, in consequence, differences in petroleum generation. The carbonate organic-rich interval of Sudr Formation has generated oil around the Early Pleistocene (~0.9 Million year before present (Mabp)) in SH-A1 well. Combining the results of the petrophysical, geochemical and the 1D basin modeling studies provides a comparison between the generation potential with time for the carbonate organic-rich intervals. The maturity of the organic-rich interval varies from immature to early mature with a different tendency to produce oil depending on the kerogen type, basin evolution and burial through time. Most hydrocarbons were generated in the Pleistocene. This means that hydrocar- bon generation has occurred after the deposition of post South Gharib Formations. If sufficient residual kerogen has remained, increased temperature, as a result of the combined effect of Ter- tiary deposition and elevated temperature in the Late Tertiary, may have led to late–stage oil ex- pulsion in favorable parts of the basin. Key words: Shoab Ali Oilfield – Sudr Formation – Gulf of Suez - Basin Modeling. Journal of Environmental Sciences, 2013; Vol. 42, No. 4 : 569-605