| 智利艾斯康迪达铜矿床地质特征与成矿模式 |
| |
| 引用本文： | 曹 冲,赵元艺,常玉虎,卢 伟,李 运,曾 辉.智利艾斯康迪达铜矿床地质特征与成矿模式[J].地质通报,2015,34(6):1227-1238. |
| |
| 作者姓名： | 曹 冲 赵元艺 常玉虎 卢 伟 李 运 曾 辉 |
| |
| 作者单位： | 1. 中国地质大学(北京)，北京 100083；2. 中国地质科学院矿产资源研究所，北京100037 |
| |
| 基金项目： | 中国地质调查局项目（编号：1212011120326） |
| |
| 摘 要： | 艾斯康迪达矿床是位于智利北部安第斯铜矿带的世界第三大斑岩型铜矿床,铜储量3156.7×104t,其形成主要与始新世晚期—渐新世的石英二长岩-花岗闪长斑岩岩株有关,构造上受多梅科断层系统的控制。该矿床拥有典型斑岩型铜钼矿床的热液蚀变类型,包括钾长石化、黑云母化、石英-绿泥石-绢云母化、泥化与青磐岩化。与成矿有关的侵入岩年龄在38Ma左右,辉钼矿Re-Os年龄为36.1~33.7Ma。流体包裹体特征表明,该区域矿床成矿热液分为早期高温的岩浆热液和晚期岩浆热液与地下水混合的低温低盐度热液2期。高场强元素的负异常、稀土元素La/Yb值特征与Sr-Nd同位素比值特征表明,成矿斑岩是混入少量壳源物质的幔源岩浆演化来的。形成于南北向多梅科断层与北西向线性构造交会位置的转换拉伸环境,对艾斯康迪达矿床成矿斑岩的侵位具有关键性作用。
|
| 关 键 词： | 艾斯康迪达矿床 多梅科断层系统 辉钼矿Re-Os年龄 流体包裹体 转换拉伸环境 |
Geological features and metallogenic model of the Escondida copper deposit in Chile |
| |
| CAO Chong,ZHAO Yuanyi,CHANG Yuhu,LU Wei,LI Yun,ZENG Hui.Geological features and metallogenic model of the Escondida copper deposit in Chile[J].Geologcal Bulletin OF China,2015,34(6):1227-1238. |
| |
| Authors: | CAO Chong ZHAO Yuanyi CHANG Yuhu LU Wei LI Yun ZENG Hui |
| |
| Institution: | 1. China University of Geosciences, Beijing 100083, China;2. Insitute of Mineral Resourses, Chinese Academy of Geological Sciences, Beijing 100037, China |
| |
| Abstract: | The Escondida deposit, located in the Andes copper belt of northern Chile, is the third largest porphyry copper deposit in the world with copper reserves of 31.567 millon tons. The formation of this deposit, controlled by Domeyko Fault System in terms of structure, is associated with the emplacement of a late Eocene-Oligocene quartz monzonitic to granodioritic intrusive stock complex hosted by Paleocene andesite. The typical types of hydrothermal alteration observed in the porphyry Cu-Mo deposit include K-feldspathization, biotitization, quartz-chloritization-sericitization, propylitization and advanced argillitization. The age of intrusive rocks related to mineralization is at about 38Ma. The Re-Os molybdenite ages are between 36.1Ma and 33.7Ma. The characteristics of fluid inclusions show that the regional metallogenic hydrothermal fluids can be divided into two phases: the early magmatic hydrothermal fluid with high temperature and the late hydrothermal fluid with low temperature and low salinity mixed with both magmatic hydrothermal fluid and groundwater, respectively. Negative anomalies of high field strength elements as well as characteristics of rare earth elements La/Yb and Sr-Nd isotope ratios reveal that the ore-bearing porphyries were derived from mantle magma mixed with a small amount of crustal material. The transtensional environment formed in the location of intersection between the SN-trending fault system of Domeyko and NW-trending linear structure played a key role in the emplacement of the ore-bearing porphyries in Escondida area. |
| |
| Keywords: | Escondida deposit Domeyko fault system Re-Os molybdenite ages fluid inclusions transtensional environment |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《地质通报》浏览原始摘要信息 |
| 点击此处可从《地质通报》下载免费的PDF全文 |
|
