الفهرس 
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Abstract
This thesis deals with geology, petrography and geochemistry of basement rocks cropping out in the southern part of Esh- El Mallaha, North Eastern Desert, Egypt. With special emphasis on the associated dykes and veins.
The study area of Esh El-Mallaha range, is located at some 35 km north of Hurghada city, at the Red Sea coast, between latitudes 27° 27` and 27° 36` N and longitudes 33° 27` and 33° 35` E. the study reveals that the basement rocks are composed of two rocks groups. The oldest is represented by Dokhan volcanics and the younger is post-tectonic calc-alkaline – alkaline granites (younger granites). The dykes and veins are related to doming and rifting. They are melilite basalt, lamprophyre, olivine gabbros, aplites, carbonatite, columbite-bearing quartz veins and pegmatites.
The Dokhan volcanic represented by basic units mainly of basalt, basaltic andesite and andesite characterized by porphyritic, trachytic and amygdaloidal textures. The basalt is tholeitic while the basaltic andesite and andesite are calc-alkaline.
The acidic unit is mainly of andesite, dacite, rhyodacite and their equivalent tuffs. They are porphyritic, unvesiliferous and of calc-alkaline nature. The rocks exhibit some crystal fractionation and crustal contamination and mixing en root to the surface.
The granite is of alkali type post-tectonic, within plate tectonic setting. It affect Dokhan volcanics giving cordiorite hornfelsic rocks and composed of buff K-feldspar, sodic plagioclase and quartz (20%) and biotite (> 5%).