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The last stages of the continental collision during the closure of the Neotethyan ocean in central Anatolia are characterized by post-collisional H-and A-type granitoids intruding both the metamorphic country rocks and allochthonous ophiolitic rocks of the central Anatolian crystalline complex. Available Rb-Sr and K-Ar whole-rock and mineral age data on the Hand A-type granitoids in central Anatolia are inconsistent. To better constrain the geological relevance and the timing of the change in the chemical character of magmatism in the wake of the Alpine orogeny in Anatolia, we re-evaluated the geochemical characteristics and dated titanite from representative H-(Baranadag quartzmonzonite: BR) and A-type (Ç amsari quartz-syenite: CS) granitoids by the U-Pb method. BR is a high-K calc-alkaline intrusion with mafic microgranular enclaves and shows enrichment of LILE relative to HFSE. The alkaline CS displays higher SiO 2 , Na 2 O+K 2 O, Fe/ Mg, Rb, Th and HFSE with corresponding depletion in CaO, MgO, Fe 2 O 3 tot , P 2 O 5 , Ba, Sr, and Ti. Chondritenormalized REE patterns of the BR and CS samples have LREE-enriched and flat HREE patterns, whereas CS differs from BR by higher LREE enrichment and lower MREE and HREE contents. Mineralogical and geochemical characteristics suggest that BR and CS were not products of the same magma source. BR was derived from a subduction-modified depleted hybrid-source and CS had an enriched mantle source with significant crustal contribution. The U-Pb titanite ages of the Htype central Anatolian granitoids (BR) and the A-type granitoids (CS) are 74.0±2.8 and 74.1±0.7 Ma, respectively. The coeval evolution of post-collisional/ calc-alkaline H-to A-type magmatism was possibly associated with source heterogeneity and variable involvement of continental materials during the evolution of these granitoids. These new age data constrain the timing of the onset of a post-collision extensional period following the Alpine thickening within the passive margin of the Tauride-Anatolide platform, which occurred before the opening of the latest Cretaceous central Anatolian basins.

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The rare-metal granites of the Nubian Shield are commonly associated with Nb−Ta and Sn mineralization. The magmatic and hydrothermal evolution of these granites and their relation to the Nb−Ta and Sn mineralization need further investigations. This study reports new mineral chemistry, wholerock geochemical, and Sr−Nd isotopic data for the Abu Dabbab granites in the Central Eastern Desert of Egypt to provide new insights into the formation mechanisms of the granites and their associated rare-metal mineralization. The granites consist mainly of albite, orthoclase, quartz, and Li-phengite, with accessory minerals including cassiterite, columbite, tantalite, wodginite, and Hf-zircon. Geochemically, they are peraluminous with high SiO 2 , alkalis, Rb, Nb, Ta, Sn, F, and low contents of MgO, CaO, and P 2 O 5 . The granites are characterized by distinct rare-earth element tetrad effects (TE 1,3 = 1.8−2.5), with strongly negative Eu anomalies and are extremely depleted in Ba, Sr, P, and Ti. These features imply that they are typical muscovite peraluminous highly evolved granites. Isotopically, they display positive εNd(t) values (+1.11 to +8.32) and two-stage Nd depleted model ages (t DM2 ) between 0.68 and 1.13 Ga, suggesting a juvenile magma source of the Neoproterozoic age. The Abu Dabbab granites could be formed by dehydration melting of muscovite-rich crustal materials followed by extensive fractional crystallization with a significant role of magmatic−hydrothermal fluids during the transitional orogenic stage of the Nubian Shield.