新疆青河卡拉先格尔铜矿带Ⅱ-Ⅲ矿区含矿斑岩锆石年龄及地质意义  

Ages of the zircons from ore-bearing porphyries in Ⅱ-Ⅲ ore area of Kalaxianger porphyry copper ore belt in Qinghe, Xinjiang and its geological significance

作　　者：相鹏[1,2] 张连昌[1,2] 吴华英[1] 张晓静[1] 陈志广[1] 万博[1] 

机构地区：[1]中国科学院地质与地球物理研究所中国科学院矿产资源研究重点实验室,北京100029 [2]南京大学内生金属矿床成矿机制研究国家重点实验室,南京210093

出　　处：《岩石学报》2009年第6期1474-1483,共10页Acta Petrologica Sinica

基　　金：中国科学院知识创新工程主要方向项目(KZCXZ-YW-107);十一五国家科技支撑计划重点项目(2006BAB07B01-03);南京大学内生金属矿床成矿机制研究国家重点实验室开放基金(14-08-9)资助.

摘　　要：新疆青河卡拉先格尔斑岩铜矿带位于阿尔泰山脉东南缘,NNW向可可托海-二台断裂与NW向额尔齐斯-玛因鄂博断裂交汇处偏东南位置。该矿带由卡拉先格尔Ⅰ、Ⅱ、Ⅲ号和玉勒肯矿区组成,其含矿斑岩主要为花岗闪长斑岩和石英闪长玢岩,围岩为中泥盆统北塔山组玄武岩,其中围岩局部地段也发生了矿化。矿石矿物主要由浸染状黄铜矿、辉钼矿和斑铜矿以及细脉状黄铜矿组成。本文对卡拉先格尔Ⅱ和Ⅲ铜矿区含矿斑岩中的锆石进行LA-ICP-MS U-Pb定年,结果表明含矿斑岩的锆石时代分别为390.2±4.9Ma和393.3±9.8Ma,反映了含矿斑岩侵入时代为中晚泥盆世。结合区域构造背景和火山岩-侵入岩地球化学等资料,综合分析表明该斑岩铜矿的成矿构造背景为中晚泥盆世岛弧环境。Kalaxianger porphyry copper ore belt lies on the southeastern margin of the Altay mountains, which is located southeast to the junction of the NNW Keketuohai-Ertai fault and the NW Erqis-Mayinebo fault. It is composed of Kalaxianger Ⅰ, Ⅱ, Ⅲ and Yuleken ore areas. Granodiorite porphyry and quartz diorite porphyrite are the main ore-bearing porphyries. Besides, basalts in the Middle Devonian Beitashan Formation are the main wall rocks, which are partly mineralized. Ore minerals consist of disseminated chalcopyrite, molybdenite, bornite and veinlet chalcopyrite. Zircons LA-ICP-MS U-Pb dating shows that the zircon ages of ore-bearing porphyries in Kalaxianger Ⅱ and Ⅲ ore areas is 390.2±4.9Ma and 393.3±9.8Ma, respectively. This result suggests that the intrusion epoch of ore-bearing porphyries is in Middle-Late Devonian. Combining regional tectonic setting, volcanic and intrusive rocks with some geochemical data, comprehensive analysis indicates that the ore-forming tectonic setting of the copper deposits is island arc in Middle-Late Devonian.

关 键 词：卡拉先格尔 斑岩铜矿 阿尔泰南缘 锆石LA-ICP-MSU-PB定年 

分 类 号：P618.41[天文地球—矿床学] P597.3[天文地球—地质学]