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Several outcrops of felsic melt, commonly known as oceanic plagio-granites, appear as melt pockets, irregular bosses, and dikes. Three main rock successions were exposed in the Abu Dabbab area: ophiolitic sequence, island arc assemblage, and rare metal-bearing albite granites. Plagio-granite is composed mainly of plagioclase and quartz, and chemically contains high SiO2, Al2O3, and Na2O values. The petrogenetic and geochemical studies concluded that the magmas of plagio-granites and associated felsic rocks were derived from partial melting of highly depleted mantle harzburgite and/or pre-existing oceanic crustal rocks (basalts and/or gabbros). The geochemical characteristics reveal that Abu Dabbab plagio-granites are identical to the typically low-K series of ophiolitic complexes and resemble the ocean ridge granites. Elements such as Co, Nb, Pb, and Nd in Abu Dabbab plagio-granites have high Clarke concentrations (more than 1.88). This indicates Abu Dabbab plagio-granite derived from partial melting of pre-existing oceanic crustal rocks. The average concentration values of 238 U and 232 Th are lower than those of the world's average and the average activities in granitic rocks. The scope of estimated exercises generally contrasted as their quality in rock tests relies upon their physical, synthetic, and geo-concoction properties and the appropriate condition. [ABSTRACT FROM AUTHOR]

Younger granite bodies form two arches, the western and the eastern (WA, EA), which extend from the south northwards from the Meatique, ophiolitic group-island arc rocks, to the large older granite outcrop to the north. This paper concerns the feasibility of exploration in the El-Erediya-Ria El-Garah-El-Gidami-El-Missikat Y Gr regions. Fieldwork and remote sensing, together with geochemical, petrochemical, and mineralogical studies, are used to show the controlling factors, routes, and the origins of the deposits. Remote sensing is used to delineate the different rock units. Normal and strike–slip NW, NNE faults, veins, fractured ENE shear zones, and alteration zones of magmatic-hydrothermal fluids are discussed. Granites are considered using petrochemical diagrams as resources. These rocks are categorized as syeno- and alkali feldspar granites. Geochemical binary relationships recognized the granites are highly fractionated calc-alkaline-altered Monzo-, syeno-, and alkali feldspar granites formed in the active continental margin. The observed positive Ga vs. Cu, Zn, and Ni correlations are used for epithermal-magmatic-hydrothermal polymetallic veins and mineralized greisen zones. Negative Cu vs. Mo correlation patterns show probable Mo-porphyry deposits in the deeper zones at the contact point between porphyritic perthite and perthite granitic El-Erediya mass. The Zr/Sr between 1.65 to 2.93 plus fluorites in El-Missikat and up to 5.48 plus fluorites in El-Erediya show both U-poor at El-Missikat and U-rich deposits at El-Erediya. The recorded U, Th, Cu, and Pb vertical zoning sequence of deposition differentiates U aureole and deposit zones. The estimated lateral zoning sequences of deposition of these elements define the centers of U deposits. Pathfinders for the deposit of the examined area include the positive Fe2O3 vs. Mg O and Fe2O3 vs. Ca O correlations, and also negative Rb/Sr vs. K/Na and Rb vs. Sr ones, can be applied to future prospecting for similar U-F-Au-W-Mo deposits in the Eastern Desert of Egypt. [ABSTRACT FROM AUTHOR]

Field and geochemical observations of the granitoids of the Homrit Waggat area in the central Eastern Desert of Egypt reveal two magmatic phases. The early phase of weakly deformed subduction‐related calc‐alkaline rocks includes tonalite and granodiorite. We name the later phase the Homrit Waggat Pluton (HWP); it includes undeformed syenogranite, alkali feldspar granite, and minor albitized granite. The tonalite and granodiorite have distinct negative Nb–Ta anomalies and lower alkalis, REE, Nb, Zr, and Hf than the HWP. The early magmatic pulse is a subduction‐related suite, likely generated by underplating of mantle‐derived magmas that triggered partial melting of mafic lower crust; mixing of these melts led to intermediate magma that further fractionated to tonalite and granodiorite. The HWP granites of the late magmatic pulse are transitional from a subduction‐related to an anorogenic within‐plate environment, plausibly generated by post‐collisional lithosphere delamination. Although the parent magma of the HWP was I‐type, extensive fractional crystallization produced residual liquids with A2‐type character. Albitized granites are found only along the outer margin of the HWP, and contacts with the alkali feldspar granite are gradational, suggesting fluid interactions at a late stage of crystallization. The original textures of the albitized granites are preserved, but their bulk composition was modified by the production of Na‐rich minerals and the removal of K, REE, and some trace elements by fluids. [ABSTRACT FROM AUTHOR]