Granitoids in the Gabal El-Urf area in Eastern Egypt consist of a monzogranite pluton,
belonging to the Younger Granite province, emplaced in granodioritic rocks. Whole rock Rb–Sr dating
indicate ages of 650±95 Ma and 600±11 Ma for the granodiorites and monzogranites, respectively.
The granodiorites (65–70% SiO2) are calc-alkaline and metaluminous with low Rb/Sr, Th and Nb contents,
moderate enrichment in the LILE (K2O, Rb, and Ba) and display most of the chemical and field
characteristics of syn-to late-tectonic I-type granitoids described elsewhere in the
Arabian–Nubian Shield. The monzogranites (72–77% SiO2) are metaluminous to mildly peraluminous, highly
fractionated and depleted in Al2O3, MgO, CaO, TiO2, Sr and Ba with corresponding enrichment in
Rb, Nb, Zr, and Y. They can be correlated with the undeformed post-orogenic granites in the
Arabian–Nubian Shield that chemically resemble A-type granites emplaced in extensional settings. The
mineralogical and chemical variations within the granodiorites and monzogranites are consistent with
their evolution by fractional crystallization. The granodiorites have a low initial 87Sr/86Sr ratio (0.7024)
and high ∈Nd values (+6.9–+7.3) and are significantly different from those
(initial 87Sr/86Sr ratio=0.7029, ∈Nd values=+5.2–+5.8) of the monzogranites.
These data suggest a predominant mantle
derivation for both granite types and demonstrate that they originated from different source materials.The granodiorite melt was most probably generated through vapour-saturated partial melting of an
early Neoproterozoic depleted mafic lower-crust reservoir due to crustal thickening associated with
orogenic compression and/or arc magma underplating. The mineralogical and geochemical data of
the A-type monzogranites are consistent with their derivation as a residual granitic liquid from a
LILE-enriched mafic magma through crystal-liquid fractionation of plagioclase, amphibole, Fe–Ti
oxides and apatite. The parental mafic magma was originated in the upper mantle due to crustal
thinning associated with extension in the late stage of the Neoproterozoic crustal evolution of north-eastern
Egypt.
Corrigendum to “U-Pb zircon geochronology and geochemical constraints on the Ediacaran continental arc and post-collision Granites of Wadi Hawashiya, North Eastern Desert, Egypt: Insights into the ~600 Ma crust-forming Event in the northernmost part of Arabian-Nubian Shield” [Precambrian Research 345 (2020) 105777]