geochemical and mineralogical relationships between post-orogenic plutonism and volcanism for some selected areas, southern sina, egypt

The present work deals with geochemical and mineralogical relationships of the post-orogenic plutonism and volcanism of some selected areas from southern Sinai, Egypt. This can be achieved through studying their petrogensis and tectonicsetting to find out the genetic relationship between the plutonic rocks and the corresponding volcanic. The study includes the field work, petrography, geochemistry, mineral chemistry and ore microscopy. Distribution of uranium and thorium in the differen2. Rusis - Rutig 3. Urn Shuki - Abu Khusheib1- Iqna- Sharay’a area: is located between latitudes of 28° 50’ - 28° 52’ N and longitudes of 33° 44’ - 33° 48’ E.The area occupies about 150 knr’. It can be reached through asphaltic and desert car tracks following wadies Feirain.El Akhdar, El-Berra and Iqna to the concerned area. Iqna Sharay’a is covered by granitic and volcanic rocks cross cut by dykes swarms. Iqncoarse grained red in color intruded the surrounding country rock mainly with intrusive sharp contacts. Volcanic rocks of Iqna-Sharaya are generally very hard, massive, with greyishbrown color and spotted with pinkish and white phenocrysts of potash feldspar, plagioc1ase and quartz.