An Overview on the REE-Mineralized Alkaline Granites in Egypt, with Special Reference to the Abu Khruq and Gara El Hamra Bodies |
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Authors: | Hamdy M Abdalla |
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Institution: | Nuclear Materials Authority, P.O. Box: 259-C.N. 21111, Alexandria, Egypt [e-mail: ] |
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Abstract: | Abstract. The REE-mineralized alkaline granites in Egypt are divided into the following three classes: (1) Mesozoic, anorogenic nepheline syenite ring complexes with REE amounting up to 1.3 %, particularly in their fenitized parts (e.g. Abu Khruq), (2) an orogenic peralkaline syenite-granite, composed of i) Zr, Nb, - REE, and Th-enriched peralkaline granite-syenite complexes with REE amounting up to 0.5 % (e.g. Um Hibal, Tarbite North and South, Gharib, and Zarget Naam) and ii) Y, Th, HREE, and P-enriched post-Cretaceous peralkaline complexes that intrude the Phanerozoic rocks of the Southwestern Desert with REE amounting up to 2 % (e.g. Gara El Hamra), and (3) upper Proterozoic, post-orogenic siderophyllite alkali feldspar granite with REE amounting up to 0.8 %, particularly in their apical miarolitic pegmatites and albitized zones (e.g. Kadabora-Abu Dob and Um Naggat). Special attention is given to the Abu Khruq and Gara El Hamra granitic bodies. |
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Keywords: | Egypt peralkaline syenite REE alteration |
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