الفهرس 
Introduction
Location and TopographyOnly 14 pages are availabe for public view
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Abstract
Feiran-Solaf belt in Southwestern Sinai is selected to study and investigate the pegmatite and aplite dykes and viens as characteristic rock unit. Field studies revealed that pegmatites are perpetually intrude the older metamorphics of Feiran-Solaf belt, and conversely cut by dykes. Pegmatite contacts with the country rocks are often sharp and non-reactive, but rarely graditional or reactive.
The pegmatite can be classified chronologically related to its creation time in the country rock linked to the deformational structural events that affected on the area into:
• The first phase as the oldest (completely of pegmatite) formed with the action of local derivation mechanism from the country rocks.
• The second phase (composed of concordant or discordant pegmatite and aplite) generated during the folding generation that affected on the area. Nondisplacement intrusion is the creating mechanism.
• The third phase (composed of aplite and pegmatite) after the intrusion of granitoids that deformed to gneiss or gneissose granitoids and before the fault movements and dyke extrusions. This type of magmatic origin is unaffected by the folding but cut by the dykes and fault system. This multiply generated phase could be formed by permissive displacement mechanism along the joints or fracture system.
The studied pegmatites have variable composition ranging from quartz diorite to quartz syenite. They are phaneritic rocks of commonly hypidiomorphic granular and porphyritic textures. Feldspar and quartz are the chief component of these rocks, while the insignificant mafic constituents comprise only biotite and/or its duteric alteration products. Zircon is the essential accessory mineral generally occurred in pegmatites.
These pegmatites posses calc-alkaline nature, and a prevalent metaluminous to slightly peraluminous character showing an apparent enrichment in the total alkalis, as a result of their highly differentiated nature. Temperatures were estimated between 699.23˚C and 916.85˚C and averaging 767.42˚C by zirconium saturation calculations.
Paleotectonic environment investigations infer that the examined pegmatites are of calc-alkaline character I-type granite. They are continental arc granites intruded at active continental margin pre- and syn-plate collision as the volcanic arc granite.