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The Gabal Ras Zarieb area, located west of Quseir City in Egypt's Central Eastern Desert, is distinguished by two distinct granitic masses of monzogranite and alkali feldspar granite. This research looked at field relations, geochemistry, and petrographic analysis to define the petrogenesis of these granites. GRZ granites are intruded with sharp obvious contacts into the island arc metavolcanics and metavolcaniclastics. The geochemical results demonstrate that alkali feldspar granite varies considerably from monzogranite in terms of composition, display a rise in SiO2 and total alkalis, and a decrease in Al2O3, TiO2, FeOt, MgO, and CaO. In comparison to monzogranite, alkali feldspar granite contains a higher concentration of Rb, Y, Zr, and Nb, as well as U and Th. With the exception of three samples, the REE patterns indicate modestly positive Eu anomalies, Eu/Eu*(1.6–2.1) for monzogranite, while alkali feldspar granites exhibit substantially negative Eu anomalies, Eu/Eu*(0.1–0.15), showing plagioclase fractionation. The monzogranite is calc-alkaline, metaluminous to peraluminous, I-type granite, and post-collisional, whereas the alkali feldspar granite is metaluminous, post-collisional, and A-type affinity, suggesting a transitional tectonic setting. Moreover, the monzogranites are formed by partial melting followed by fractional crystallization. The alkali feldspar granite is created directly from residual magma by the process of fractionation. [ABSTRACT FROM AUTHOR]

The area between wadi Dungash–wadi Shait in the South Eastern Desert of Egypt comprises ophiolitic nappes structurally overthrust on island arc‐related metasedimentary–metavolcanic rocks, which are traversed by several granitoids, gabbroic and basaltic rocks. This paper focuses on uncovering laterite zones utilizing field geological, mineralogical and geochemical attributes of the investigation region. Laterites are distributed at the border between Neoproterozoic and Phanerozoic rocks. The laterite deposits are developed after the emplacement of Natash flows as a result of lateritization process in tropical regions, during the Late Cretaceous. The laterite sections comprise a sequence from the top to the base, oxide laterite, plasmic laterite, saprolith and bedrock. The laterite sections consist of hematite and goethite together with small quantity of gibbsite. Geochemically, the laterite profiles are marked by an increase in Fe content and decrease in Si from the top to the bottom. Fe2O3 is the most abundant with 30.09–54.67 wt.%, Al2O3 vary from 18.01 to 32.78 wt.%, and SiO2 vary from 15.05 to 19.43 wt.%. Advanced Spaceborne Thermal Emission and Reflection Radiometer images are utilised to characterize a primer laterite zone. The band ratio 4/5 is found to be efficient in defining the laterite soil in the studied area. [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]