熔体包裹体的形成、改造和分析方法及其矿床学应用  

Formation,Modification and Analytical Techniques of Melt Inclusion,and Their Applications in Economic Geology

作　　者：张道涵[1] 魏俊浩[1] 付乐兵[1] 王大钊[2] 

机构地区：[1]中国地质大学资源学院,湖北武汉430074 [2]中国地质大学地球科学与资源学院,北京100083

出　　处：《地球科学（中国地质大学学报）》2017年第6期990-1007,共18页Earth Science-Journal of China University of Geosciences

基　　金：国家自然科学基金项目(No.41302065)

摘　　要：熔体包裹体研究不仅广泛应用于火山岩和部分侵入岩系统,而且因其具有可以保存岩浆初始挥发分和金属组成的优势,近来也逐步应用于矿床学领域.在介绍熔体包裹体形成机制和捕获后成分改造的基础上,简要归纳了目前常用的熔体包裹体分析方法,以斑岩型Cu-(Mo-Au)和斑岩型Mo成矿系统为例,重点介绍熔体包裹体在矿床学领域的应用,包括成矿金属和挥发分含量的测定,以及熔体-流体分配系数测定等方面.然而,熔体包裹体在捕获后均会受到不同程度的成分改造,且对于大多数造岩矿物内的熔体包裹体,其成分改造的具体机制仍不明了,因此在实际应用过程中,需要对其组成进行具体分析和甄别.随着分析技术的改善和提高,熔体包裹体捕获后具体成分改造机制有待进一步查明,进而推动熔体包裹体的应用.现阶段熔体包裹体在斑岩型Cu-(Mo-Au)和斑岩型Mo成矿岩浆系统的成功应用表明,相比全岩地球化学研究,熔体包裹体已成为研究成矿岩浆体系内成矿金属和挥发分演化的重要手段.Melt inclusion has been widely used in the research of volcanic and some magmatic systems,and now gradually applied to economic geology because of its absolute advantage over whole-rock analysis in preserving the primary metal and volatile composition of ore-forming magmas.In this paper,we firstly present melt inclusion formation and post-entrapment modification on its composition,then summarize the commonly used analytical techniques for melt inclusion studies,and finally take porphyry Cu-（Mo-Au）and porphyry Mo systems as examples to introduce its applications in economic geology,including determination of ore-forming metals,volatile composition,and fluid-melt partition coefficients.Considering the facts that most melt inclusions have been modified to a certain degrees after their entrapment,and that the modification mechanism for most rock-forming minerals has not been well understood,attention has to be paid to the melt inclusion data and associated interpretation.With the improvement of analytical methods,such ambiguous post-entrapment modification mechanism may be resolved in the near future,and in turn it can promote the applications of melt inclusion.The successful applications of melt inclusion in porphyry Cu-（Mo-Au）and porphyry Mo systems confirm that melt inclusion has been an important and powerful tool in studying ore-forming metals and volatile evolution in ore-forming magma systems in comparison with whole-rock study.

关 键 词：熔体包裹体 斑岩型Cu-(Mo-Au)矿床 斑岩型Mo矿床 电子探针 二次离子质谱 激光剥蚀电感耦合等离子体质谱 

分 类 号：P597[天文地球—地球化学]