Superposed Deformation in the Northern Suez Rift, Egypt: Relevance to Hydrocarbons Exploration

Abstract

Detailed subsurface studies of the northern part of the Suez Rift and adjacent areas indicate the superposition of two different episodes of deformation. During the earlier (Late Cretaceous) phase of deformation, folds with NE‐SW oriented axes were formed in northern Egypt as a result of convergence between Africa and Eurasia and the closure of the Neotethys. During the later (early Miocene) deformation., NW‐oriented normal faults were formed as a result of the opening of the Suez Rift. Borehole data have shown that a belt of NE en échelon folds with NE‐SW axes exists in the subsurface in the northernmost part of the rift, between Ayun Musa and the Sukhna‐1 well, soulth of Geble Ataqa. This fold belt represents the SW continuation of the en échelon folds exposed in the Mitla Pass, to the NE of the rift. Another pre‐rift structure is the offshore extension of the Wadi Araba structure as a SE‐facing monocline. This offshore structure also represents the continuation of the Geble Somar structure, on the eastern shoulder of the Suez Rift. The Geble Somar and Wadi Araba Structures represent the southernmost prerift folds in northern Egypt. Pre‐rift folds in the study area stood high above sea‐level during the Palaeocene and early Eocene. Upper Cretaceous and/or older rocks in the cores of these folds were later unconformably covered by middle Eocene rocks. The presence of Late Cretaceous folds should be taken into consideration when exploring for hydrocarbons in this part of the Suez Rift. Borehole data in NE Egypt also indicate the presence of Late Cretaceous folds underneath the almost flat‐laying Tertiary rocks in the northern part of the Eastern Desert. These folds are condidered to be potential hydrocarbon traps in this relatively poorly‐explored area.

Slope sediments of a Paleocene ramp-to-basin transition in NE Egypt

“…Predominantly carbonate sediments were deposited along an E±W running tectonically induced uplift that covered parts of the present North Galala and Wadi Araba. This uplift represents the southernmost area affected by the Syrian Arc fold belt (Moustafa 1995). It was formed as a consequence of the closing Tethys since Turonian times (Lüning et al 1998).…”

From platform to basin: the evolution of a Paleocene carbonate margin (Eastern Desert, Egypt)

“…The Syrian Arc System was formed during the collision between the African and European plates, starting in early Turonian times. A dextral transpressive reactivating of Mesozoic half-grabens resulted in a series of inverted, uplifted and folded grabens (e.g., Moustafa and Khalil 1995). The NGWA High is separated by east-northeasttrending faults (Bandel and Kuss 1987) that run perpendicular to the younger Gulf of Suez faults, which resulted from the Miocene opening of the Gulf.…”

Tectonically driven carbonate ramp evolution at the southern Tethyan shelf: the Lower Eocene succession of the Galala Mountains, Egypt

“…The Syrian ArcFold-Belt was formed as a result of the initial collision of the African and Eurasian Plates in the Late Turonian (e.g. Moustafa and Khalil 1995;Scheibner et al 2003). The emergence of the Galala platform has been documented for the Campanian/Maastrichtian (Scheibner et al 2003).…”

“…In the Early Eocene, the Egyptian shelf is especially strongly aVected by tectonism, which is related to the northward movement of the African craton towards Eurasia as well as the reactivation of Mesozoic fault systems (e.g. Shahar 1994; Moustafa and Khalil 1995;Hussein and Abd-Allah 2001). Thus, the evolution of carbonate platforms at the Egyptian shelf is controlled by those tectonic constraints and requires a regional approach beyond the general platform stages of Scheibner et al (2005).…”