Duobuza porphyry copper-gold deposit is a newly discovered deposit, which is located in the middle of Tibet plateau and in the west of Bangonghu-Nujiang metallogenic belt. K-feldspar from the potassic alteration zone was analyzed by Ar/ Ar daling technique, and these results yielded a plateau age of (118. 31 ±0. 60) Ma and a reverse isochron age of (118. 30 ± 0. 79) Ma with initial 40 Ar/36 Ar =291 ± 17 , indicating that potassic alteration age in Duobuza porphyry deposit ranges from 119 to 118 Ma and coincide with the mineralization age ( molybdenite Re-Os age, 119-118 Ma ). The magmatic-hydrothermal evolution of Duobuza deposit should be from magmatic stage (around 120 Ma) to potassic alteration and mineralization (119-118 Ma) , then to phyllic alteration (118-115 Ma) , and the duration of magmatic-hydrothermal evolution probably persisted 5 million years.%西藏多不杂斑岩铜金矿是在班公湖—怒江成矿带发现的第一个斑岩型矿床.通过对多不杂矿床蚀变钾长石进行40Ar/39Ar年代学测试获得,蚀变钾长石的坪年龄为(118.31 ±0.60) Ma,反等时线年龄为(118.30±0.79) Ma,它们代表多不杂矿床钾化蚀变的年龄为119～118 Ma,与成矿年龄同期.多不杂矿床形成的岩浆-热液过程为,由岩浆期(约120Ma)演化至钾化和成矿期(119～118 Ma),再演化至绢英岩化期(118～115 Ma).
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