ABSTRACT
Zabargad (St. John) Island is a small island about 80 km off the Egyptian Red Sea coast. The crystalline rocks of the island comprise spinel lherzolite-troctolitegabbro and a metamorphic complex. Bonatti and others (1981, 1983 etc.) believe that the crystalline rocks represent a tectonically uplifted fragment of sub-Red Sea lithosphere (caused by Red Sea tectonics). Conversely, El-Gaby et al. (1987) consider the island a detached block of the Pan-African basement exposed in the Eastern Desert of Egypt. The gneiss complex consists of amphiolites and felsic gneisses. The amphibolites contain relics of igneous pyroxenites and gabbros which have recrystallized into mafic granulites representing the lower continental crust (Seyler & Bonatti 1988).
