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Granitoid rocks of the Wadi Um Geir-Wadi Allaqi (WUGA) area represent a Neoproterozoic calc-alkaline magmatic episode in the Southeastern Desert of Egypt. The rocks range in composition from high-Ca (>1 wt%) metaluminous to low-Ca (<1 wt%) peraluminous granites. The former are compatible with a volcanic-are environment, whereas the latter are related to within-plate A-type granites. The WUGA granites are highly fractionated and enriched in Rb, Nb, Y, and REE except for Eu. with corresponding depletions in Mg, Fe, Ti, Ga, Sr, and Ba. BEE fractionation patterns and Eu/Eu* values decrease from high-Ca metaluminous granite (La/Yb-n = 2.46 - 4.68; Eu/Eu* = 0.32 - 0.73) to low-Ca peraluminous granite (La/Yb-n = 0.37 - 1.23; Eu/Eu* 0.01.2 - 0.032, respectively). Major-element modeling suggests that the granitic types are products of a single stage of crystal fractionation. The low-Ca peraluminous granite formed by extreme fractionation of the high-Ca metaluminous granite liquid, with plagioclase, K-feldspar, and biotite as the dominant fractionating phases.

Radioactivity in the WUGA, attributed to the presence of thorium and uranium, is associated with the younger granites, especially within shear zones, fault planes, and pegmatitic bodies. The accessory assemblage of peraluminous granites consists of monazite, xenotime (in low-Ca varieties), fluorite, garnet, apatite, zircon, tantalite, columbite, Th-orthosilicate (huttonite), umohoite, uranophane, beta-uranophane, and betafite-pyrochlore minerals. Metalumious granites contain allanite, titanite, apatite, zircon, minor monazite, and Th-orthosilicate thorite). The genesis of secondary U minerals is mainly attributed to the action of oxidized groundwater on previously corroded primarly U minerals. These Secondary uranium minerals were deposited near the surface by evaporation.