Zircon U-Pb, Hf isotope and trace element geochemistry from the newly found Neoproterozoic granitoids in Wadh-Khuzdar area, Balochistan, Pakistan: constraints on magma genesis and tectonic settings

• A-type granitoids of Neoproterozoic age ca. 630–753 Ma, were discovered in Wadh-Khuzdar area of Balochistan, Pakistan. • Positive εHf(t) values of +9.4 to +15.2 in zircons suggest a depleted mantle source that generated the parental magma. • Geochemical (bulk-rock and zircon trace) data show rift-related and within-plate tectonic setting. This study investigates the newly found granitoids on the western margin of the Indian Plate, exposed in the Wadh-Khuzdar area of Balochistan, Pakistan. The emplacement of these granitoids has important implications for understanding the tectonic evolution of the Rodinia Supercontinent during the Neoproterozoic era. To understand magma genesis and tectonic settings, detailed petrography, whole-rock geochemistry, zircon U-Pb/Lu-Hf isotope analyses, and trace element geochemistry were conducted. In total, 50 rock samples were collected from two exposed bodies of granitoids. The studied rocks are K-feldspar rich, exhibit high K 2 O + Na 2 O contents (6.2–11.5 wt%), and display geochemical characteristics similar to A‐type granitoids which are generally silica-rich, show relatively higher contents of alkalis, FeO/(FeO + MgO), rare-earth elements, and Ga/Al ratios but low Eu anomalies, Al 2 O 3 , Sr Ba, and Ti. Their chemistry reflect high-T/low P formation conditions, typical of intra-plate rifting and post-collisional setting. From 10 representative samples, 154 zircon grains (8 from Eastern and 2 samples from Western body) were investigated for internal structures, and analyzed for U-Pb isotope, trace element geochemistry, and Lu-Hf isotope analysis on selected dated spots. The studied zircons exhibit oscillatory zoning, showed higher Th/U ratios of 0.4 to 1.4, and displayed steep chondrite-normalized rare-earth element patterns, positive Ce and negative Eu anomalies all indicate their magmatic origin. The U-Pb zircon ages (630 to 753 Ma), εHf(t) values of + 9.4 to 15.2, zircon-saturation temperatures from whole-rock (695 to 1031 °C), Ti-in-zircon values (716 to 1017 °C), suggest their magmatic crystallization from juvenile crust derived from a depleted mantle source. Subduction-related arc-type, rift-related/within-plate, and mantle upwelling played a crucial role to generate these granitoids. Similarities in petrography, ages, and Hf isotope data provide a strong link that the studied granitoids generated from a coeval magma, in the same tectonic regime, which generated several other granitoid of the region that include the Malani Igneous Suite in India, Nagar Parkar Igneous Complex in Pakistan, Seychelles, and Madagascar. All these Neoproterozoic granitoids formed from magmatism related to the subduction of the Mozambique Ocean, followed by a rift and extensional tectonic regime within and along the western margin of the Rodinia supercontinent.