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RESEARCH PRODUCT

The Wadi Onib Mafic-Ultramafic Complex: A Neoproterozoic Supra-Subduction Zone Ophiolite in the Northern Red Sea Hills of the Sudan

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Publisher Summary The Wadi Onib mafic–ultramafic complex represents the best preserved, though tectonically dismembered, Neoproterozoic (Pan-African) ophiolite in the northern Red Sea Hills of the Sudan. Arabian–Nubian shield (ANS) is the northern continuation of the Mozambique belt and, together, they have been referred to as the East African Orogen (EAO). The Wadi Onib mafic—ultramafic complex constitutes one of the best preserved, though tectonically fragmented, ophiolitic sequence within the ANS and makes up the major part of the prominent, southwest to northeast oriented Onib–Sol Hamed suture. An improved understanding of the composition and history of this complex has important regional tectonic significance and helps to understand global crustal evolution in the Neoproterozoic. Based on detailed petrography, representative suites of ultramafic rocks, gabbros, basic dykes and basaltic pillow lavas as well as chromitiferous ores were selected for major and trace element analysis. Though the basalt–andesite arc assemblages locally show rapid facies changes along a predominantly southwest to northeast bedding/foliation strike, they generally display comparable lithotypes.