الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Several recent giant gas discoveries have established a major hydrocarbon province in the East Mediterranean. Exploration success will depend heavily on understanding the tectonostratigraphic evolution of this basin. Large 2D and 3D seismic data have transformed the way geoscientists understand basin evolution and fill and petroleum system of onshore and offshore North Sinai. Therefore, this study aims to focus on two targets, ‘deep and shallow’. The first one is ‘deep target’, which evaluates the Cretaceous carbonate build up from a petroleum potential point of view. Secondly is ‘shallow target’, which deals with solving some mismatch in gas initial in place GIIP estimations and evaluating lithology facies classification for Plio-Pleistocene gas zones.
Concerning the deep target, the onshore and offshore North Sinai basins are examined for their tectonostratigraphic evolution, as well as Cretaceous carbonate buildups as illustrated by numerous significant discoveries by the Zohr gas field in 2015 in the offshore area and Sadot - Raad gas field in 1975 - 1987 onshore. This study assesses possible extension in other onshore and offshore North Sinai plays by examining basin-scale risk of individual play elements’ effectiveness. It evaluates the petroleum potential of a buildup in Cretaceous carbonates via a comprehensive methodology for integrating subsurface (borehole and seismic) and surface (lithostratigraphy, biostratigraphy, paleoecological) data from onshore and offshore Sinai. In doing so, plays are predicted, and potential risks are reduced. The results predict that the location of Cretaceous carbonate buildups plays a key role in the North Sinai Basin. There are also examples of how Cretaceous carbonate models are matching on the basin’s surface and subsurface.
As for the shallow target, it is also important to mention that, during conventional seismic interpretation in the study area, identifying Direct Hydrocarbon Indicators (DHIs) within the Pliocene-Pleistocene reservoir sequence has been challenging due to the low seismic resolution and complex structures of the reservoir. Such a case would result in the static volumes calculated for different DHIs not matching the dynamic models generated for different gas production levels (for example, the static model down estimates gas production). By enhancing and broadening the frequency spectrum of seismic data, this enables better mapping of the top and base of the reservoir and a better estimation of gas initial in place (GIIP). The procedures introduced in this study that can effectively enhance the resolution of seismic data; are the Seismic Colored Inversion (CI), Seismic Spectral Blueing (SSB) technique, and spectral decomposition attributes extraction. Through the use of a CI and SSB technique, they were improving seismic data resolution by increasing frequency bandwidth, aiding in revealing and extracting features (DHIs). The minimum vertical resolution of seismic data was increased from 31 to 17 meters using SSB and 31 to 23 meters using CI, resulting in a match with drilled wells in reserve estimation.
Furthermore, rock physics modeling and AVO inversion techniques enable retrieval of elastic properties such as P-impedance and Vp/Vs ratio from the seismic angle stacks. As part of this process, the litho-facies is classified and the gas, brine sands, and shale is identified throughout the study area.