投稿时间：2011-09-22
修订日期：2012-04-10
中文摘要:西藏甲玛铜多金属矿床位于冈底斯火山岩浆弧的东段,是冈底斯成矿带的重要组成部分,也是最具代表性的产于后碰撞伸展环境中的超大型斑岩-矽卡岩-浅成低温热液铜多金属矿床。文章以该矿区斑岩体中各类脉体的矿物特征,尤其是脉体石英显微结构以及微量元素特征为切入点,初步划分出3大类5个阶段的岩浆-热液流体。金属硫化物主要沉淀于第2、第4和第5阶段。脉体石英中Al、Fe、K含量的变化指示了流体pH值的变化以及与钾化有关的蚀变。流体的温度范围跨度极大,从602℃到130℃,即从斑岩型高温岩浆流体演化为浅成低温热液型流体。岩浆热液生命周期至少持续3 Ma,具有多期多阶段性,开始于岩浆房中岩浆-热液流体的出溶,一直演化至成矿作用结束,贯穿整个岩浆-热液成矿系统。含矿流体中金属元素沉淀得益于岩浆流体pH值的改变。
Abstract:The Jiama polymetallic copper deposit is located in eastern Gangdise volcano-magmatic arc,which is an important component part of the Gangdise metallogenic belt. The Jiama deposit is a typical superlarge porphyry-skarn-epithermal polymetallic copper deposit related to post-collision. The combination of scanning electron microscope-cathodoluminescence (CL) and LA-ICP-MS microanalysis of Al, Ti, K and Fe in veined quartz has yielded results permitting a greater understanding of the complex mineralization of the Jiama porphyry-style deposit. The data obtained demonstrate the relationship between quartz precipitation, dissolution and ore deposition with the variation of ore-forming fluid through time. Five major quartz generations were identified. Ti-in-quartz geothermometer and fluid inclusion analysis show that the crystallization temperature from JMi to JMⅴ varies between 602°C and 130°C. The CL and trace element signatures from JMi to JMⅴ stages of the porphyries show features similar to those observed in porphyry-style deposits of other areas. This suggests that a common sequence of quartz crystallization occurred during the formation of early veins in many porphyry copper systems.
文章编号：
中图分类号：P618.41
文献标志码：
基金项目:本文得到地质调查项目"念青唐古拉地区成矿条件研究与找矿靶区优选(编号:N0807)"、技术开发项目"西藏墨竹工卡县甲玛铜多金属矿床地质特征及找矿方向研究项目(编号:E0804)"、公益性行业科研专项经费"我国典型金属矿科学基地研究"项目(200911007)、国家自然学基金项目(40902029)和云金集团项目"滇西地区金多金属矿成矿规律及成矿系列研究"的联合资助
引用文本：
彭惠娟,汪雄武,侯林,秦志鹏,周云.2012.西藏甲玛铜多金属矿床石英脉特征[J].矿床地质,31(3):465~479PENG HuiJuan,WANG XiongWu,HOU Lin,QIN ZhiPeng,ZHOU Yun.2012.Characteristics of quartz in stock work veins from Jiama copper polymetallic deposit, Tibet[J].Mineral Deposits31(3):465~479
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