投稿时间：2016-08-18
修订日期：2017-02-28
网络发布日期：2017-11-06
中文摘要:林子宗群火山岩是青藏高原规模最大的火山岩带，但对该火山岩与成矿关系的研究较少。文章以斯弄多低硫化浅成低温热液型银铅锌矿床为例，对矿区主要的赋矿火山岩开展了精确的LA-ICP-MS定年和全岩地球化学分析，获得矿区火山岩锆石U-Pb年龄在62~65 Ma之间，这些岩石属于高钾钙碱性-钾玄岩和过铝质岩石系列，相对富集轻稀土元素（∑LREE/∑HREE=3.39~13.21）和大离子亲石元素（LILE，如Rb、K、Sr）；亏损重稀土元素（LaN/YbN=3.02~16.47）和高场强元素（HFSE：Nb、Ta、Ti、P），显示出弧火山特征。结合其他研究数据及区域上典型矿床成岩成矿时代特征，作者指出斯弄多低硫化浅成低温热液型矿床的形成与林子宗群火山作用（62~65 Ma）密切相关，是火山作用驱动地热体系的产物，成岩成矿发生在印度-亚洲大陆初始碰撞期的陆缘火山弧背景下。
Abstract:The Linzizong volcanic rocks constitute the largest volcanic belt in the Tibetan Plateau. However, effective studies of the relationship between volcanic rocks and mineralization remain very insufficient. In this paper, the authors carried out an accurate LA-ICP-MS dating and whole rock geochemical analysis of the ore-hosting volcanic rocks from the Sinongduo low sulfidation epithermal Ag-Pb-Zn deposit and obtained the U-Pb ages between 62 Ma and 65 Ma, suggesting that the rocks belong to high potassium calc-alkali to shoshonite and peraluminous rock series; all the rocks show the relative enrichment in light rare earth elements (∑LREE/∑HREE=5.48~6.95) and large ion lithophile elements (LILE:such as Rb, Sr, K), and relative depletion in heavy rare earth elements (LaN/YbN=5.53~8.54) and high field strength elements (HFSE, Nb, Ta, Ti, P), implying arc volcanic features. Combined with other research data and the characteristics of the metallogenic age, the authors hold that the formation of Sinongduo low sulfidation epithermal deposit was closely related to Linzizong Group volcanic rocks (62~65 Ma) and the deposit seems to be the product of the volcanic system which occurred in the continental volcano-tectonic setting at the initial time of India-Asian collision.
keywords:geochemistry Linzizong Group volcanic rock low sulfidation epithermal Sinongduo volcano-tectonic setting Gangdise
文章编号：
中图分类号：P618.52;P618.42;P618.43
文献标志码：
基金项目:本文获地调项目《西藏雄村-普桑果斑岩-矽卡岩型铜多金属矿成矿地质背景与找矿潜力调查》（编号：12120114068401）和西藏中瑞矿业发展有限责任公司项目（XZZR-2015）联合资助
引用文本：
丁帅,陈毓川,唐菊兴,谢富伟,胡古月,杨宗耀,施硕,李于海,杨洪钰.2017.林子宗群火山岩与成矿关系:以斯弄多浅成低温热液型矿床为例[J].矿床地质,36(5):1074~1092DING Shuai,CHEN YuChuan,TANG JuXing,XIE FuWei,HU GuYue,YANG ZongYao,SHI Shuo,LI YuHai,YANG HongYu.2017.Relationship between Linzizong volcanic rocks and mineralization:A case study of Sinongduo epithermal Ag-Pb-Zn deposit[J].Mineral Deposits36(5):1074~1092
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