内蒙古迪彦钦阿木超大型钼矿床成矿流体特征及成矿机制  

The characteristics of oreforming Fluids and ore-forming mechanism of the Diyanqinamu super-large molybdenum deposit,Inner Mongolia

作　　者：王瑞良 张招崇[1] 曾庆栋[2,3,4] 王永彬 郭祺[1] 褚惠燕 郭云鹏 郭理想[2,3] WANGRuiLiang;ZHANGZhaoChong;ZENGQingDong;GUOQi;CHUHuiYan;GUOYunPeng;GUOLiXiang(Faculty of Geosciences and Resources,China University of Geosciences,Beijing 100083,China;Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;Institutions of Earth Science,Chinese Academy of Sciences,Beijing 100029,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国地质大学地球科学与资源学院,北京100083 [2]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 [3]中国科学院地球科学研究院,北京100029 [4]中国科学院大学,北京100049

出　　处：《岩石学报》2018年第12期3582-3596,共15页Acta Petrologica Sinica

基　　金：国家自然科学基金重大项目(41390443);国家深地资源专项项目(2017YFC0601306)联合资助.

摘　　要：迪彦钦阿木钼矿是近年来发现的一个超大型斑岩钼矿床,位于大兴安岭中段二连浩特-东乌旗多金属成矿带。本文主要对迪彦钦阿木钼矿床的流体包裹体及硫同位素进行了系统研究。迪彦钦阿木钼矿发育有四个成矿阶段:石英-钾长石阶段、石英-辉钼矿阶段、石英-多金属硫化物阶段及石英-萤石-碳酸盐阶段。矿床不同阶段的流体包裹体中,富气相(V类)、富液相(L类)和含子晶(S类)包裹体大量共存。显微测温结果显示,第一阶段包裹体均一温度为492～> 600℃,盐度分为两部分:5. 36%NaCleqv(L类)和32. 39%～64. 90%NaCleqv(S类);第二阶段包裹体均一温度为292～510℃,盐度为4. 49%～19. 92%NaCleqv(L类)和28. 43%～70. 21%NaCleqv (S类);第三阶段包裹体均一温度为206～388℃,盐度为2. 24%～22. 71%NaCleqv(L类)和28. 62%～54. 64%NaCleqv(S类);第四阶段包裹体均一温度、盐度最低,均一温度为133～288℃,盐度为0. 88%～7. 86%NaCleqv。流体具有从高温、高盐度向低温低盐度演化趋势。前三个成矿阶段L类、V类和S类包裹体大量共存,端元包裹体均一温度相近,盐度相差很大,表明发生了强烈的流体沸腾作用。多期次的流体沸腾作用是迪彦钦阿木矿床的主要成矿机制。硫同位素研究显示,δ^(34)S值的变化范围是1. 78‰～10. 41‰,暗示着迪彦钦阿木钼矿成矿物质主要来自于岩浆。Diyanqinamu deposit is a super-large porphyry molybdenum deposit found in recent years,it’s part of the ErlianhaoteDong Ujimqin polymetallic belt,located in the north central part of Daxing’anling Mountains. This paper mainly studies the fluid inclusions and sulfur isotopes of the Diyanqinamu Mo deposit. Four hydrothermal stages of the Diyanqinamu deposit are recognized:quartz-K-feldspar,quartz-molybdenite,quartz-polymetallic sulphides and quartz-fluorite-carbonate satges. In the fluid inclusions at different stages of the deposit,gas-rich( V-type),liquid-rich( L-type) and daughter-mineral-bearing( S-type) inclusions coexist in large quantities. The results of microscopic temperature measurement show that the homogenization temperature of the first stage inclusions is 492 ~ > 600℃,the salinity is obviously divided into two parts: 5. 36% NaCleqv( L-type) and 32. 39% ~ 64. 90%NaCleqv( S-type); The second stage inclusions homogenization temperature is 292 ~ 510℃,the salinity is 4. 49% ~ 19. 92% NaCleqv( L-type) and 28. 43% ~ 70. 21% NaCleqv( S-type); In the third stage inclusions,the homogenization temperature is 206 ~ 388℃and the salinity is 2. 24% to 22. 71% NaCleqv( L-type) and 28. 62% ~ 54. 64% NaCleqv( S-type). The homogenization temperature and salinity of the fourth stage are 133 ~ 288℃,0. 88% ~ 7. 86% NaCleqv respectively. The fluid has the trend of evolution from high temperature and high salinity to low temperature and low salinity. The L-type,V-type and S-type inclusions coexisted in the first three mineralization stages. The uniform temperature of the end-envelope inclusions was similar,and the salinity varied greatly,indicating that a strong fluid boiling effect occurred. The multi-stage boiling action of the ore-forming fluid seems to have been the dominant factor for metallic sulfide deposition. Sulfide isotope studies have shown that the δ34 S value of the overall range of 1. 78% ~ 10. 41‰,suggesting that ore-forming materials of the Diyanqinamu Mo deposit were mainly derived from the

关 键 词：流体包裹体 硫同位素 超大型斑岩钼矿床 迪彦钦阿木 大兴安岭 

分 类 号：P618.65[天文地球—矿床学]