中文摘要:位于冈底斯造山带中西段的雄村特大型铜金矿床产于日喀则弧前盆地北缘的旦狮庭组火山岩中。文章通过对雄村矿床矿体外围英安斑岩、矿带内花岗闪长斑岩脉和矿体深部花岗闪长斑岩3个样品的锆石U_Pb SHRIMP年龄测定，获得成岩年龄分别为（195±4.6）Ma （MSWD=1.48）、（179±5）Ma（MSWD=2.6）和（175±5）Ma（MSWD=3.2），表明这套火山岩是形成于早侏罗世而不是此前一致公认的晚白垩世。在已知成矿时代为始新世（38.11 Ma）的情况下，这些早侏罗世容矿火山岩时代的确定自然就排除了该矿床属斑岩型或海底喷流沉积型成因的可能性。另外，矿床受NWW向断裂破碎带控制，缺少浅成低温热液矿床的蚀变矿化组合，成矿流体具有岩浆水与大气水混合特征，矿石硫化物与容矿火山岩具有一致的S、Pb同位素组成。这些成矿特征与胶东焦家式金矿具有很大的相似性，推测该矿床很可能属于破碎带蚀变岩型铜金矿床。
Abstract:The superlarge Xiongcun copper_gold deposit in the west_central segment of the Gangdese orogenic belt occurs in volcanic rocks of Danshiting Formation, and its origin remains a problem of controversy. In this paper, zircon U_Pb SHRIMP dating was made for three whole_rock samples collected separately from the dacite porphyry outside the ore body, a granodiorite porphyry dyke within the deposit and the granodiorite porphyry at the depth of 366 m in a drill hole, and the result shows that their formation ages are (195±4.6) Ma with MSWD=1.48, (179±5) Ma with MSWD=2.6 and (175±5) Ma with MSWD=3.2, respectively. These ages suggest that this volcanic suite was formed in Early Jurassic instead of formerly widely_accepted Late Cretaceous. If this age collation is valid for the whole Rigaze forearc basin, the generation age of the Rigaze forearc basin as well as the collision history of the Indian plate with the Eurosian continent should be wholly reconsidered. Under the background that the ore_forming age is already known (38.11 Ma), the age data of the Early Jurassic ore_hosting volcanics naturally rule out the possibility that the Xiongcun Cu_Au deposit belongs genetically to the porphyry or seafloor_exhalation type. This Cu_Au deposit is controlled by a NWW_trending fault and lacks the alteration_mineralization association typical of an epithermal deposit. Its ore_forming fluids are characterized by mixture of magmatic and meteoric water, and its ore sulfides contain the same S and Pb isotopic compositions as the ore_hosting volcanics. All these metallogenic features reflect great similarity to the Jiaodong “Jiaojia_style" gold deposits. The authors therefore tend to believe that the Xiongcun superlarge deposit belongs probably to thealtered cataclastite type Cu-Au deposit.
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基金项目:“973"项目《印度与亚洲大陆主碰撞带成矿作用》(项目编号: 2002CB412605)
引用文本：
曲晓明，辛洪波，徐文艺.2007.三个锆石U-Pb SHRIMP年龄对雄村特大型铜金矿床容矿火成岩时代的重新厘定[J].矿床地质,26(5):512~518.2007.Collation of age of ore_hosting volcanics in Xiongcun superlarge Cu-Au deposit on basis of three zircon U-Pb SHRIMP ages[J].Mineral Deposits26(5):512~518
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