Abstract We describe a fractured dolomite reservoir in the Miocene syn-rift succession of the Gulf of Suez, and the impact of fractures on the increase in the water cut during production from this reservoir and the measures taken to overcome this problem. The Issaran Field includes two dolomite reservoirs (the Upper and Lower Dolomite). The Lower Dolomite reservoir has a highly fractured zone (HFZ) corresponding to a brittle layer that extends down-dip below the highest know water level, allowing the flow of water from the water-wet area to other parts of the reservoir and, thus, causing an increase in the water cut in the wells. Setting an inflatable packer above the HFZ in open holes, perforation above its level in cased holes and reaching total depth of new wells above the HFZ are recommended to decrease the water cut. Accidental hydraulic fractures might develop by steam injection at pressures exceeding rock fracture pressure. These fractures and critically stressed natural fractures allow injected steam to pass laterally through the reservoir along interconnected natural fractures.

Abstract Detailed study of outcrop and subsurface data of North Sinai indicates the existence of a NE–SW oriented region with very large asymmetric folds lying between the Nile Delta hinge zone and the Sinai hinge belt. The steep southeastern flanks of these folds are often associated with high-angle reverse faults. These folds continue northeastward in the Naqb Desert toward the Dead Sea transform. The North Sinai folds represent inversion anticlines formed by inversion of Mesozoic (Jurassic and probably Cretaceous) extensional basins during Late Cretaceous to pre-Miocene times. Mesozoic extension is related to the divergence between Afro-Arabia and Eurasia and opening of the Neotethys whereas inversion is related to the convergent movement between these two plates. The acme of inversion was at Campanian time. The central Sinai hinge belt is a zone of ENE–WSW oriented, right-lateral strike–slip faults that separate the folded area to the north from the tectonically stable area of central and southern Sinai. It responded to the convergent movement between Afro-Arabia and Eurasia by dextral transpression on the faults. Later reactivation of the eastern edges of these faults by drag on the west side of the Dead Sea transform took place in post-Miocene to Recent times.