Genesis of Permian granites along the Kangguer Shear Zone, Jueluotage area, Northwest China: Geological and geochemical evidence

Permian mafic and felsic intrusions occur along the Kangguer Shear Zone (KSZ) in the Jueluotage area, Eastern Tianshan, northwest China. This study focuses on the Permian felsic intrusions (288-276.2 Ma). Systematic geological and geochemical investigations show that granite plutons in the western KSZ (Dikan, Guandao and Hongshi) have lower Al and higher alkali contents than those in the eastern KSZ (Longdong, Huangshan and Baishandong). The western granite plutons experienced higher degrees of crystal fractionation than the eastern granite plutons. Both of the western and eastern Permian granite intrusions along KSZ were derived from juvenile crust, the Nd-Pb isotopic characteristics of which exhibit mixed compositions of DM and EMII type mantles. Both of the western and eastern Permian granites along KSZ were formed within post-collision background. The Dikan, Guandao and Hongshi plutons in the west KSZ sector were formed in an extensional tectonic setting, whereas the Longdong, Huangshan and Baishandong plutons in the east KSZ formed in a compressional tectonic setting.