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Khour Abalea in Abu Rusheid area is located at the midst part of the cataclastic rocks having U-shaped It was formed as a result of deep strike-slip faults, some forming shear zone in some trends. Two forms of pegmatites have been distinguished (pockets and veins) occurring within the cataclastic rocks as hosted rocks. Petrographically, they consist of quartz, orthoclase, microcline and micas.The identified minerals in the studied pegmatites can be grouped into primary uranium minerals (uraninite), secondary uranium minerals (kasolite, uranophane and meta-autunite), thorium minerals (thorite and uranothorite), the niobium-tantalum minerals (columbite, ferro-columbite, samarskite, euxenite and fergusonite), the accessories (zircon, monazite, cassiterite, pyrite and fluorite) and mica (muscovite, phlogopite and fluor-phlogopite) as well as the opaques (hematite and goethite).Geochemically, the studied pegmatite (S-type) are calc-alkaline and peraluminous in nature. It is highly fractionated possibly due to hydrothermal alterations. The REEs display clear tetrad effect of M-type accompanied with relative enrichment of the HREE over the LREE and marked negative Eu anomaly (Eu/Eu* =0.03 to 0.36). The calculated tetrad effect in the pegmatite demonstrates clear tendency towards the ratios of the common isovalents such as Zr/Hf, Nb/Ta and Y/Ho. However, the tetrad effect seems not to be mutual with the content of Na2O and Rb/Sr. The absence of coherence between tetrad effect and soda or potassic contents may indicate insignificant role of the Na-or K-metasomatism in developing the tetrad effect.Detailed spectrometric survey of the study pegmatite revealed their enrichment of eU (49-306 ppm) and eTh (76-634 ppm) and the potential anomalous radioactivity is attributed to both magmatic and hydrothermal processes.

An economically important rare-metal mineralization is recorded in the cataclastic rocks at Wadi Abu Rusheid area, South Eastern Desert of Egypt. Radiometric measurements of the main varieties of cataclastic rocks (protomylonites, mylonites, ultramylonites) show that their equivalent thorium (eTh) content is 7560, 8660 and 6210 ppm, whereas the equivalent uranium (eU) is 2544, 4170 and 790 ppm respectively. Microscopic examination, X-ray diffraction (XRD) and grain counting techniques revealed that thorite, zircon and columbite are the predominant radioactive minerals in all rock varieties , together with minor amounts of xenotime, cassiterite and sulphides. Beside these minerals, uranophane, kasolite and metaautunite occur as inclusions in other minerals. Physical upgrading of these minerals was carried out using gravitative separation technique. Applying the proposed flowsheet, it is possible to attain a good concentrate for these minerals with an acceptable recovery. It is recommended to subject the final concentrates to hydrometallurgical treatments to extract the important metals.

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Siwa Oasis is a closed depression situated in the north western portion of the Western Desert of Egypt between Longitudes 25º 16' and 26º 12' E, and Latitudes 29º 06' and 29º 24' N. Three soil profiles were selected to represent the main geomorphic units and their associated soil groups in the studied area. Ghazallat soils are characterized mainly by sand and sandy loam textures, as well as sandy clay loam in the deeper layers. The chemical analyses of soil solution indicate that the cultivated soil samples show slightly saline to moderately saline nature, whereas the soils under reclamation and the barren ones are strongly saline. In general the organic matter contents are low, while CaCo3 content increases from the deeper samples to the higher ones. As for the soil reaction of Ghazallat area, it is clear that these soils are ranging from mildly to moderately alkaline. It is noticed that Na + cation > Mg ++ , Ca ++ and Mg ++. The predominance of Na + and Mg ++ is a good reflection of the involvement of marine origin of the soils. On the other hand, the anionic distribution has the following descending order Clanion > SO 4-> HCO 3-, where CO 3-is almost negligible. The distribution of the fertility elements are of low to moderate levels. The bulk samples analysis indicates that quartz, calcite, feldspars (albite) minerals are the main dominant mineral associations in all soil profiles of Ghazallat region. Dolomite and anhydrite as well as gypsum presented in some depths of soil profiles. Illite and kaolinite represent the identified clay minerals in the studied soil samples. The radiometric studies show that all of the studied soils in the area are not related to the uraniferous soils (uranium content not exceeding 6ppm).