The influence of mantle processes on passive margin formation - a case study from the island of Zabargad, Red Sea, Egypt

Since the discovery of plate tectonics the study of the Red Sea rift system has played an important role in understanding how a continent splits. Despite the attention this area has attracted for years, many problems remain still open or are controversial . I. e.: (i) Did fluid infiltration and metasomatism (including the formation of plagioclase and amphibole) in the continental lithospheric mantle in the rotated fault blocks take place during the formation of the Red Sea, or is it much older? (ii) What i s the relationship between rifting, basin formation, intraplate magmatism and dooming? (iii) At what stage of stretching did magmatism start? (iv) What is the influence of the Afar plume on the Red Sea rift? These problems are adressed using an integrated , multidisciplinary approach. Detailed petrographic and geochemical studies of mantle rocks exposed on the island of Zabargad are designed to qualitatively and quantitatively assess the modification of lithospheric mantle compositions through time. The in formation derived from the study of the Zabargad samples will be used during modelling of lithospheric extension in order to evaluate and quantify the influence of mantle processes on basin formation and continental breakup. The aim of the modelling is to establish a classification of typical basin evolution scenarios and to identify which scenario is most compatible with the Zabaragad data.