PETROLOGICAL, MINERALOGICAL AND GEOCHEMICAL STUDIES ON THE OPHIOLITE AND ISLAND ARC ASSOCIATION OF WADI HAMMARIYA, EAST OF GABAL UMM SHAGHIR, CENTRAL EASTERN DESERT, EGYPT

The present work is a petrological, geochemical and mineralogical study of Wadi Hammariya area which located in the central Eastern Desert of Egypt. The majority of this area is covered mainly by two lithologically different units, these are: dismembered The ophiolite assemblage comprises peridotite serpentinites, metapyroxenites, antigorite chrysotile serpentinites, carbonate chrysotile serpentinites, talc antigorite carbonate serpentinites; tremolite-actinolite chrysotile antigorite schists, chloritite Geochemical analysis of the present ophiolitic assemblage suggest that the present serpentinites belong to supra-subduction zone ophiolites and can be compared with the ophiolitic mafic-ultramafic cumulates. The metagabbros, amphibolites and metavolcanicsThe opaque mineralogical investigation reveals that serpentinites are enriched (up to 12% by vol.) by homogeneous and zoned chromite together with magnetite. The metagabbros are ilmenite and titanomagnetite bearing rocks (up to 5% by vol.). Amphibolites aThe island arc association comprises metavolcanics (meta-andesites, fluidal meta-andesites, foliated meta-andesites, coarse and fine lithic-crystal intermediate metatuffs, metadacites, metarhyodacites and metagranophyres) and volcaniclastic metasedimentarThe geochemical results of the metavolcanics show that they are derived from calc-alkaline magma in an island arc or plate margin settings. On the other hand, the geochemical interpretation of the volcaniclastic metasedimentary rocks refers to metagreywac