A newly identified cryogenian (ca. 806 ma) basement tonalite gneiss from the Eastern Karakoram, NW India: Constraints from geochemistry and zircon U-Pb geochronology

The Karakoram Terrane (KT) represents the southern margin of Eurasian Plate, mainly consisting Late Jurassic-Early Cretaceous subduction-related granites and post-collisional Miocene leucogranites, which intrude Neo-Proterozoic basement. We report for first time existence Cryogenian KT basement as recorded from geochemistry geochronology tonalite gneiss (ca. 806 Ma) in southeastern terrane, NW India. Geochemically, studied is slightly peraluminous (Molar Al 2 O 3 /CaO+Na O+K O=1.1), calc-alkaline volcanic-arc granitoid, strongly fractionated REE (La N /Yb =33.99), high Sr/Y =19.75, more akin to its affinity with Tonalite–trondhjemite–granodiorite (TTG)/adakite. whole-rock elemental data suggest that likely sourced ancient mafic lower crust where garnet remained residue. petrogenetic modeling suggests melt similar observed can be generated through ∼50% partial melting a garnet, clinopyroxene, amphibole assemblage. synthesis comparison present published Proterozoic magmatic records on rocks dictate produced most served parental development TTGs Southern Pamir evolved granitoid Central Tibetan terrane. propose southeast product Neoproterozoic Andean-type orogeny formed northwestern Rodinia supercontinent. Thus, our study favors time, position within Cimmerian belt along other East Asian continental blocks.