Sequence Stratigraphy and Sands Geometry of the Langhian Sequences in East Zeit Field, Gulf of Suez, Egypt

Farhoud, Khamis Sherif, Tarek Abdel Fattah Kamel, Heider Osman Saad, East Zeit Petroleum Company, Cairo, Egypt

Despite the complication of seismic data in the Gulf of Suez by the extensive Late Miocene evaporite cap, a seismic sequence stratigraphic analysis has been conducted on the Langhian sequences in East Zeit field. The oil potential Langhian sands throughout the study area are subdivided into two systems tracts, 1) the Early Langhian highstand system tract Asl sand, and 2) the Late Langhian lowstand to transgressive system tract Markha sand. Good well control in the area allowed effective calibration and integration the seismic data to correlate these Miocene sequences. Within the context of sequence stratigraphy con­cepts, these wells and seismic sections were divided into a series of 3rd order depositional sequences, chronostratigraphic maximum flooding surfaces and sequence boundaries, which are age dated with high resolution biostratigraphy and stratigraphic analysis, and have been correlated within the framework of the global cycle-chart. Subsequently, these 3rd order depositional sequences are subdivided into systems tracts on the basis of character­istic lithology, paleobathymetry, well-log signature and synthetic modeling. Beyond the seis­mic scale, the individual system tract was also subdivided into a series of “Parasequences” on the same mentioned basis, which permitted well-by-well correlation on a higher resolu­tion scale. This type of stratigraphic analysis enabled a more accurate delineation and map­ping of the sand geometry for these two systems tracts that permitted the definition of the play concept for these reservoir sands; as deep marine turbidites and submarine fans con­trolled by paleostructural-highs and low relief areas generated by basinal block faulting and tilting at Langhian time.