Petrogenesis, Sources, and Tectonic Settings of Triassic Volcanic Rocks in the Ela Mountain Area of the East Kunlun Orogen: Insights from Geochronology, Geochemistry and Hf Isotopic Compositions

The Ela Mountain area is located at the easternmost point of East Kunlun Orogen, in which voluminous igneous rocks developed Triassic period, and it a good place to investigate tectonic evolution Paleo-Tethys Ocean. In this study, petrological, geochemical, zircon U-Pb geochronology Hf isotope studies were carried out on volcanic area. Dacite (239.3 ± 1.4 Ma) exhibits calc-alkaline I-type characteristics, rhyolite (237.8 2.1 similar high-K highly fractionated rock. petrogenesis shows that both dacite originated from partial melting mafic lower crust Mesoproterozoic under relatively high temperature low pressure. derived same or parent magma, they are with different differentiation degrees formed magmatic pulse activity. Differing dacite, basaltic andesite young age (234 1.2 Ma), mainly originating lithospheric mantle modified by subducted slab-derived fluids; magma was contaminated small amount crustal source components experienced fractional crystallization minerals before eruption surface. This study environment these slab failure late stage syn-collision, types sources environments. contribution provide important evidence for Middle Late syn-collisional magmatism stages. results constrain limit closure Ocean initial time extension providing information regarding regional processes activity history. They can be applied evolution, petrology, stratigraphy mineral deposits related rocks.