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西藏吉如斑岩铜矿位于冈底斯斑岩铜矿带的中段。锆石 SHRIMP U-Pb 和辉钼矿 Re-Os 年代学研究表明,与成矿相关的黑云母二长花岗岩成岩年龄为48.68±0.49Ma,成矿事件发生在48.30～50.8Ma。明显不同于冈底斯铜矿带形成于陆内后碰撞造山向伸展走滑转换的过渡环境的驱龙、冲江、朱诺等矿床(成岩成矿年龄集中在17～12Ma)。该矿床形成于印度.亚洲大陆主碰撞阶段,碰撞晚期(52～42Ma)的间歇性应力松弛造就了吉如铜矿黑云母二长花岗岩的侵位和斑岩型矿化的发育。这一成果表明,在中国西藏冈底斯斑岩铜矿带同时存在碰撞环境和后碰撞伸展环境的斑岩型铜矿。
The Tibet Jiru porphyry copper deposit is located in the middle of the Gangdese porphyry copper belt. The zircon SHRIMP U-Pb and molybdenite Re-Os chronological studies have shown that the diagenetic age of biotite monzogranite associated with metallogenesis is 48.68 ± 0.49Ma and the mineralization event occurs at 48.30 ~ 50.8Ma. It is obviously different from the deposits such as the Drivage, the Chongjiang and the Juno deposits formed in the intracontinental post-collision orogeny to the extensional strike-slip transition (the diagenetic and ore-forming age is concentrated in 17 ~ 12Ma). The deposit was formed in India during the main collision of the Asian continent. Intermittent stress relaxation in the late collision period (52-42 Ma) resulted in the emplacement and porphyry mineralization of the biotite monzogranite in the Jiuru copper deposit. This result shows that there are both porphyry copper deposits with collisional environment and post-impact extension environment in the Gangdise Porphyry copper belt, Tibet, China.