الفهرس 
Chapter (1) : introductionOnly 14 pages are availabe for public view
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Abstract
The Eastern Desert of Egypt is the northwestern extension of the Arabian-Nubian shield (ANS) between NE Africa and west Arabia. The Central Eastern Desert (CED) comprises two main lithostratigraphic units: the structural unit containing gneisses, migmatites, schists and amphibolites and the Pan–African nappes containing low–grade metamorphosed ophiolites (serpentinites, pillow lavas and metagabbros), arc metavolcanic-metasedimentary successions. Syn–tectonic calc–alkaline granites, metagabbro–diorite complex and late– to post–tectonic granites intruded these two unites.
The Sukari granites are elongated in a NNE direction and surrounded by two steep shear zones from east and west directions. These granites belong to the within–plate A–type magmatism and display a trondhjemitic affinity. They comprise alkali feldspar granite together with syenogranite and monzogranite. Their geochemical signatures suggest emplacement in an extensional tectonic regime associated with the post–collisional collapse of the Pan–African Orogeny. They range in compositions from metaluminous to peraluminous and classified as ferroan alkali–calcic to calc–alkalic rocks. These calc–alkalic granites were formed by partial melting of tonalitic to granodioritic crust at low–pressure conditions.
Magmatic temperatures are around 930°C as deduced from zircon saturation estimate. This inference is supported by the high SiO2 (> 70 wt. %) and low CaO (< 2 wt. %) contents that are similar to those of melts produced experimentally by partial melting of tonalites and granodiorites. Moreover, the Rb–Sr systematic indicates that these granitic magmas were formed at relatively shallow depth (around 20 km). The rocks show enrichment in the LILE (Rb, Ba, Ta and K) relative to HFSE (P, Ti and Y). The overall similarity of the trace element patterns suggests that the Sukari granites were derived from a similar parental magma source.
The gold mineralizations in the Eastern Desert of Egypt including Sukari gold mine region principally controlled by the conjugate shear zones of the Najd Fault System and are associated with E–W directed shortening accompanying oblique convergence between East and West Gondwana. The nature of the mineralized structures include essentially the first shear set which is N-S trending and stacked shear set that dips between 45º to 60º E. The sheared rock commonly contains strong kaolinite, where the kaolinite occurs the gold grades and sulphide content increases.