Abstract:Zhulumute quartz syenite porphyry occurs in the northern part of West Junggar. Geochemical results show that the quartz syenite porphyries are characterized by high K2O (460%~558%), total alkalies (K2O+Na2O) (814%~961%), high K2O/Na2O (1.25~1.38) ratio with A/CNK values of 1.04~1.18, belong to peraluminous and highK calcalkaline series. The quartz syenite porphyries have high total REE (176 ppm~205 ppm) contents. They are enriched in light rare earth elements (LREE) \[(La/Yb)N=6.0~10.4\], nearly flat heavy rare earth elements (HREE) \[(Gd/Yb)N=0.96~1.12\], as well as pronounced negative Eu anomalies (Eu/Eu*= 0.23~0.26). On a primitive mantle normalized diagram, they show the relative enrichment of LILE (i.e. Rb, K, U and Th) and La, Nd and Zr and relative depletion of Nb, Ta, P and Ti. Their magma sources have likely experienced fractional crystallization of plagioclase, apatite and FeTi oxides. The quartz syenite porphyries have positive εNd (t) and εHf(t) values, with young t2DM(Nd) (474~572 Ma) and t2DM(Hf) (357~931 Ma) ages, suggesting that their sources are mainly derived from the juvenile material of Paleozoic formation. They show high zircon saturation temperatures (Tzr) of 834~865℃ and are almost simultaneous with the early Permian Atype granites indicating that the northern West Junggar was a high temperature, extensional setting during early Permian.