Ganzi-Litang gold belt is located in the Eastern Qinghai-Tibet Plateau, the junction area of SongpanGanzi orogenic zones and Yidun arc orogen.The authors attempt to explore the ore-formating temperature, depth and environments of the five gold deposits, i.e.Gala gold ore district, Cuo'a gold ore district, Xionglongxi gold ore district, Ajiaiongwa gold ore district and Qukailongwa gold ore district, using electron microprobe analysis of the main gold-bearing minerals of pyrite and arsenopyrite.The mineralizing age is discussed based on the fission track age of zircon in the ore.The pyrites are characteried by lossing sulfur content and generally containing cobalt and nickel, in which the content of cobalt is from 0.04％ to 1.73％, and that of nickel is from 0.01％ to 2.97％.The mean content of cobalt is 0.43％, and the composition ratios of Co/Ni range from 0.08 to 10.04 with an average of 2.28.The pyrites have the composition ratios of Fe/( S + As) between 0.841 and 0.907,averaging 0.875.Arsenopyrite belongs to arsenic-rich sulfur type, the ratio of Fe/( As + S) is from 0.49 to 0.57 while that of As/S is from 0.73 to 0.87.Therefore, we consider that the gold deposits formed in the condition of higher oxygen fugacity, middle-shallow depths and middle-low temperature hydrotherm of 165 -250 ℃.They are the epithermal gold deposits, and the mineralizing age of gold is between 82 and 140 Ma with a multi-stage characteristics, and the ore mineralization was closely related to the alkaline magmatic hydrotherm in Yanshanian Period.%甘孜-理塘金矿带位于青藏高原东部松潘-甘孜造山带与义敦岛弧造山带的交界部位.通过对嘎拉、错阿、雄龙西、阿加隆洼和曲开隆洼等5个金矿区矿石样品中主要载金矿物黄铁矿和毒砂的电子探针分析,试图探讨区内金矿形成温度、深度和成生环境,并结合矿石锆石裂变径迹定年探讨成矿时代.研究区黄铁矿为S亏损型,普遍含Co和Ni,含量分别为0.04%～1.73%和0.01%～2.97%,其中w(Co)均值为0.43%,w(Co)/w(Ni)值为0.08～10.04,均值为2.28.w(Fe)/w(S+As)值为0.841～0.907,平均为0.875.毒砂表现出富S亏As的特点,w(Fe)/w(As+S)=0.49～0.57;w(As)/w(S)=0.73～0.87.总体上看,甘孜-理塘金矿床形成于氧逸度较高、中低温热液环境下,成矿温度以165～250℃为主,成矿部位主要为中-浅部.该金矿带的成矿时代为82～140 Ma,具有多期次特点,成矿作用与燕山期的碱性岩浆热液有关.
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