We report zircon U-Pb geochronology, major and trace elements geochemistry and Hf isotopes for the intermediate basic dykes from Kawabulak area in central Tianshan. LA-ICP-MS zircon U-Pb dating yielded a weighted mean 206Pb/238U ages of 296.1±2.5 Ma （MSWD = 1.4） and 299.5±2 Ma （MSWD = 1.07） for diorite and gabbro dykes, respectively. Geochemically, the dykes are characterized by enrichment of LILEs （Rb, U, Th）, LREE and depletion of HFSEs （Nb, Ta, Ti）. SREE varies from 69.19～234.62, while LREE/HREE changes from 3.97～11.18. （176Hf/177Hf） values of zircons from diorite dyke vary from 0.280 618～0.283 329, with corresponding εHf(t) values between -14.57～+25.06. The available data show that parental magma of studied dykes was mainly derived from a depleted mantle and experienced fractional crystallization as well as significant crustal contamination during magma emplacement. Field geological characteristics and geochemical analysis, integrated with regional data from the literature, show that the dykes were likely formed in post-collision extensional environment, indicating that South Tianshan Ocean closed prior to Early Permian in Kawabulak area.
Guzalnur Polat Nijat Abdurusul Gong Xiangkuan Cai Hongming Muzappar Muhtar Chen Yaru. Geochronology and petrogenesis of intermediate basic dykes from Kawabulak area in central Tianshan, Xinjiang[J]. Chinese Journal of Geology, 2019, 54(2): 571-589.