The East African Orogen (EAO) is an accretionaryorogen that extends from Arabia to East Africa and into Antarctica and correlatedto closure of the Mozambique Ocean, which formed in association with thebreakup of Rodinia 800–900 Ma (Stern, 1994). The Mozambique Belt is thesouthern part of the EAO and comprises mostlypre-Neoproterozoic crust with a Neoproterozoic–earlyCambrian tectonothermal overprint (Bingen et al., 2009).

The Mozambique Oceanclosed during a protracted period of island-arc and microcontinent accretionbetween850 and 620 Ma (Fritz et al, 2013). The Arabian–Nubian Shield (ANS) isthe northern part of the EAO and composed mainly of juvenile Neoproterozoiccrust (e.g. Stern, 1994, 2002; Johnson and Woldehaimanot, 2003; Johnson et al.,2011). This crust was generated when arc and back arc crust developed withinand around the margins of the Mozam-bique Ocean. The late Proterozoic(Pan-African, 900–550 Ma) Arabian–Nubian Shield (ANS) forms the suture betweenEast and West Gondwana at the northern end of the East African Orogen (EAO).

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TheArabian–Nubian Shield was caught between fragments of East and WestGondwanaland as these collided at about 600 Ma (Meert, 2003). The ANS comprisesMiddle Cryogenian–Ediacaran (790–560 Ma) sedimentary and volcanic terrestrialand shallow-marine successions unconformable on juvenile Cryogenian crust (Johnsonet al., 2013).

The ANS extends from Jordan and Ocuppied palastine in the northto Eritrea and Ethiopia in the south and from Egypt in the west to Saudi Arabiaand Oman in the east. The Nubian Shield is separated by the Red Sea from itscounterpart, the Arabian Shield. The ANS consists of gneisses, granitoids, andvarious meta-volcanic and metasedimentary rocks. The Precambrian basement of the EasternDesert of Egypt is the northwestern extension of the Arabian–Nubian Shield(ANS). The Central Eastern Desert (CED) is characterized by two distinctive tectonostratigraphicunits.

The lower unit comprises high-grade metamorphic gneisses, migmatites,schists and amphibolites and is commonly referred to as the structural basement(El-Gaby et al.,1990; Loizenbauer et al., 2001). The upper unit includeslow-grade metamorphosed ophiolite slices (serpentinites, pillow lavas, metagabbros),arc metavolcanics, arc metasediments and is com-monly referred to as structuralcover or the Pan-African nappes (e.

g.El-Gaby et al.,1990; Fritz et al., 1996;Abd El-Rahmana et al., 2012). Both the two units were intruded by syn-tectoniccalc-alkaline granites and metagabbros–diorite complex.

The later stage of thecrustal evolution of the CED is characterized by the eruption of the Dokhanvolcanic suite which is associated with the forma-tion of molasse-type Hammamatsedimentary rocks that were deposited in non-marine, alluvial fan/riverenvironments (Grothaus et al., 1979; Abd El-Wahed, 2010; Bezenjania et al., 2014).These crustal rocks were intruded by a series of late to post-tectonicgranites. The syn-tectonic granite in the CED has a magmatic emplacement age of606–614 Ma (Loizenbauer et al., 2001; Andresen et al., 2010) whereas, the lateto post-tectonic granites were emplaced at ca. 590–550 Ma (Hassan and Hashad, 1990;Rice et al.

, 1993). 

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