الفهرس 
GEOLOGICAL SETTINGOnly 14 pages are availabe for public view
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Abstract
The area locates between latitudes 28(R@ (B48C and 28(R@ (B58C 54G N and longitude 33(R@ (B26C to 33(R@ (B36CE. The study rock units can be arranged from the oldest as follows: Gneisses (Hornblende biotite gneiss and biotite gneiss), older granites (quartzdiorite and granodiorite), younger gabbros, younger granites (syenogranites), pegmatites and post granite dykes (acidic, intermediate and basic dykes). The relation between P2O5/TiO2 and MgO/CaO reflects the magmatic protolith of the studied gneisses and have felsic igneous provenance. Older granites have calcalkaline affinities, miaskitic nature and metaluminous characters and belongs to Itype granite and were emplaced during island arc regime. Younger gabbro covers about 3.7 kmp2 sat the entrance of Wadi Nisryin. Younger granites cover about 37kmp2sand exposed at Wadis Nisryin, Naba, SeihSidri, Teima and Seih and at the mouth of Wadi Sidri. Pegmatite are very coarse grained and can be classified into zoned and unzoned pegmatite. The studied syenogranites are characterized by calcalkaline to alkaline affinities. They are intruded during syncollision to postorogenic environment and presumed to be derived from magma of the dominated crustal matter source. The joints are widely distributed in more one set. The first set strikes NS and dips 50(R@ (Bto W and 64(R@ (Bto E. The second set strikes EW and dips 62(R@ (Bto both N and S. The third joint set strikes N 58(R@(BW S 58(R@(BE and dips 70(R@ (Bto NE. The distribution of uranium and thorium in the study rocks increases from basic to acidic types. There are three types of anomalies in the studied area (pegmatite veins, pegmatite pockets and fractures pegmatite). The XRD and SEM investigations of pegmatite samples reveal the occurrence of radioactive bearing minerals (monazite, thorite, bastnasite Fifteen wadi deposits samples (2025 kg for each) were collected from the wadis dissecting younger granites. By using XRD and SEMEDAX examination many minerals are identified like, minium lead oxides, cassiterite, hydroxyl apatite, dahllite, tapiolite, cerussite, lead oxides, zircon, sphene and barite. The average heavy mineral per cent increases with the decrease of size fraction. The averages of nonmagnetic mineral increase with the decrease of size fraction. Key words: Introduction, geological setting, geological structure, petrography, geochemistry, nuclear elements and mineralogy, radioactive elements, nonradioactive elements, wadi deposits.