Facies analysis and sequence-stratigraphic control on reservoir architecture: Example from mixed carbonate/siliciclastic sediments of Raha Formation, Gulf of Suez, Egypt

Mixed carbonate-siliciclastic systems are complex, and their development can sometimes be difficult to understand, given the various responses each sub-environment specific forcing, such as variation in sediment supply, climatic conditions, or available accommodation. This work integrates a detailed facies, associated with depositional environment reconstruction, all of which is placed sequence stratigraphy framework order identify different controls on reservoir architecture Upper Cretaceous (Cenomanian) Raha Formation, Gulf Suez. The study utilized outcrop data from Gabal Ekma Nezzazat, well subsurface five wells drilled through October oil field. Our findings revealed that Formation succession subdivided into eleven facies associations (FA) deposited one sequence. Abu Had Member formation consists mixed siliciclastic/carbonate packages, arranged retrogradational stacking pattern, were during period pulsative shoreline regression. As result transgression, siliciclastic input system increased, potentially due increased precipitation weathering hinterland area. upper part belongs Mellaha Sand Member, mostly composed bioturbated quartz arenite bioturbation, main Field. It was progradation testified by its progradational pattern. reservoirs divided distinctive types (G, C, Q, P, M), based factors controlling permeability (Diagenetic criteria compositional framework). outcrops-subsurface correlations indicated these laterally extensive, thicken 25 m SE 91 northwestwards. predicted intervals toward unexplored areas northern Pore-filling cement detrital matrix decreased quality minimum while, grain coating prevented collapse quality. values, consequently lowering minimum, whereas quality, retaining highest values overall pore system. aforementioned provides significant insight understanding sequence-stratigraphic control architecture. Additionally, it insights for further exploration activities carbonate/siliciclastic along Suez adjacent basin, improved units could also applied future Carbon Capture Storage projects.