Petrogenesis and Geodynamic Implications of Late Triassic Mogetong Adakitic Pluton in East Kunlun Orogen, Northern Tibet: Constraints from Zircon U–Pb–Hf Isotopes and Whole-Rock Geochemistry

Adakites or adakitic rocks usually show special geochemical signatures and are petrological probes to reveal the tectono–magmatic evolutionary history of paleo–orogenic belts. Here, we present a comprehensive study on zircon U–Pb geochronology, whole-rock geochemistry, Lu-Hf isotopes Mogetong pluton in East Kunlun orogen, Northern Tibetan Plateau, constrain its petrogenesis tectonic setting, thus implications for Paleo–Tethyan orogeny. The studied comprises quartz monzonite porphyry with crystallization age ca. 215 Ma, which is coeval their diorite enclaves (ca. 212 Ma). porphyries have intermediate SiO 2 (63.31–65.74 wt%), relatively high Al O 3 (15.52–16.02 K (2.83–3.34 Sr (462–729 ppm), but low Y (9.14–15.7 ppm) Yb (0.73–1.39 Mg # (47–55), Sr/Y (30–57) La/Yb ratios resembling typical high–K calc-alkaline rocks. Zircon Lu–Hf that samples weakly juvenile (?Hf(t) = 1.80–4.03) older model (1.00–1.14 Ga). relative content Cr (14–59 Ni (8–30 as well petrological, geochemical, isotopic data, indicates were generated by partial melting thickened lower crust certain contribution underplated mantle-derived magma slab break-off setting. This shows Late Triassic magmatism orogen may be response transition from oceanic subduction post–subduction extension, reworking ancient continental subsequent variable crust-mantle mixing major mechanism evolution orogenic belt.