الفهرس 
Northwestern GroupOnly 14 pages are availabe for public view
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Abstract
The present study is an attempt to contribute the mineral resource potential of gold deposits in Egypt (namely: Fatira and Gidami occurrences) have been chosen for a comprehensive study based on field,structural, mineralogical and geochemical investigations. This work is intended to better understanding for the characteristics, distribution controls, conditions and time of mineralization relatively to the age of the intrusion hosting granitoids to find if there is a genetic links between the gold mineralization and the evolution of the host intrusive complex as a part of the island arc section in view of the evolution of the Nubian-Shield.4.1. FATIRA GOLD-ORE The Fatira gold deposits are represented by three sites; highly altered felsite dykes and auriferous quartz vein that are cutting through granitic rocks, as well as area of shear zone between granitic and metavolcanic rocks.The petrographic study confirmed by geochemical analysis revealed that, the metavolcanic rocks are composed essentially of meta-andesite and metadolerite rocks as well as intergrowth of hornfelse in the area near of granitic intrusion. The granitic rocks are composed of quartz,plagioclase, and potash feldspars associated with biotite, hornblende,muscovite, chlorite and calcite as well as apatite, zircon, sphene and iron oxides as the main accessory minerals. Whole geochemical analysis (major oxides, trace elements) revealed that, the studied granitoids are of granodiorite composition derived form calc-alkaline magma corresponding to I-Type granite (G2-group). They were formed in the thickened crust as a result of partial melting for mantle-derived mafic underplate from the subducting oceanic slab. Granites were developed within island arc tectonic settings related to mature island arc system (Late-orogenic stage), which were formed at deep-seated environment with relatively low temperature (around 660° C) and medium pressure between (5 – 10 Kb).