Reverse Fault Geometry in The Gulf of Suez Rift Basin, Egypt

By

 Salah Abul Karamat¹, Wafik Meshref²

(1) Apache Egypt Companies, Cairo, Egypt (2) Ocean Egypt Companies, Cairo, Egypt

 A structural model is proposed to account for apparent reverse fault geometry observed in the Geisum Field, Gulf of Suez Rift Basin. The proposed model is believed to be applicable for similar worldwide rift basins. The authors propose that reverse fault geometry in extensional rifts is due to the interaction and the geometric relationship between different superimposed normal fault systems and their associated fault blocks. Reverse fault geometry in the offshore Geisum Field, in the southern Gulf of Suez, is interpreted from the repeated pre-rift sections penetrated in the vertical wells. The present work suggests that the reverse fault geometry observed in the Geisum Field is the result of the interaction between the pre-rift (oblique to the Gulf) and the superimposed early and syn-rift northwest trending (Clysmic) normal fault systems. The magnitude of throw of the different interactive faults, the dip magnitude and dip direction of the adjacent and the interrelated normal fault blocks combine to create apparent reverse fault geometry along pre-existing (oblique) normal faults. The proposed model does not require shear or strike slip movement along oblique faults. The suggested model is thought to be applicable to the Gulf of Suez subsurface geologic interpretation, but needs surface geologic support through careful structural examination of surface outcrops on both sides of the Suez Rift.