投稿时间：2020-05-11
修订日期：2020-07-24
网络发布日期：2020-09-09
中文摘要:与基性-超基性侵入体有关的Ni-Cu-PGE硫化物矿床是镍-铜-铂族元素矿床的最重要类型。传统观点认为，Ni-Cu-PGE硫化物矿床是由成矿岩浆分异演化、熔离形成的，与围岩性质关系不大。实际上，大部分基性-超基性岩浆是硫化物不饱和的，在岩浆自身演化过程中难以聚集大量硫化物而形成有经济价值的大型高品位Ni-Cu-PGE硫化物矿床。因此，壳源硫的加入是基性-超基性岩浆中硫化物浓度达到过饱和，熔离形成Ni-Cu-PGE硫化物矿床的关键。膏盐层是富含石膏等硫酸盐（SO42-）的蒸发沉积建造，除SO42-外，还富含Cl-、CO32-、Na+、K+等盐类物质，在自然界分布广、面积大，是地壳中重要的硫源层和氧化障。但膏盐层在Ni-Cu-PGE硫化物矿床中的作用长期被忽视，制约了Ni-Cu-PGE硫化物矿床成矿找矿理论的发展。文章以世界最大的俄罗斯诺里尔斯克Ni-Cu-PGE硫化物矿床为例，介绍了膏盐层与矿床分布的空间关系、石膏等硫酸盐矿物在矿床和蚀变围岩中的分布、成矿元素和硫同位素组成特征及变化规律，阐明了膏盐层在成矿中的作用和控矿机理。膏盐（SO42-）的加入，可以大幅度提高成矿系统的氧逸度，将成矿岩浆中Fe2+氧化成Fe3+，形成铁氧化物，SO42-自身被还原，向成矿系统提供还原硫S2-，与Cu2+、Ni2+等结合，形成铜镍硫化物等，使基性-超基性成矿岩浆由硫化物不饱和变为过饱和，形成硫化物小液滴，在岩浆房经聚集-熔离-富集，形成岩浆型Ni-Cu-PGE硫化物矿床。除膏盐层外，富含硫化物的地层也是形成Ni-Cu-PGE硫化物矿床的重要硫源层。
Abstract:Ni-Cu-PGE sulfide deposits related to basic-ultrabasic intrusions are the most important type of Ni-Cu-PGE deposits. The traditional view is that Ni-Cu-PGE sulfide deposits are formed by the evolution of magmatic differentiation and segregation of sulfide, having an unclosed relationship with the nature of surrounding rocks. In fact, most of the basic-ultrabasic magmas are sulfide unsaturated, and it is difficult to gather a large number of sulfides during the evolution of magma itself, forming a large-scale high-grade Ni-Cu-PGE sulfide deposit with great economic value. Therefore, the addition of crust derived sulfur is the key to the formation of Ni-Cu-PGE sulfide deposit. Gypsum layers are an evaporating sedimentary formation, widely distributed in nature. They are rich in sulfate (SO42-) and Cl-, CO32-, Na+, K+, etc. However, the role of gypsum layers in the formation of Ni-Cu-PGE sulfide deposits has been ignored for a long time, which constrains the development of the metallogenic theory of Ni-Cu-PGE sulfide deposits. In this paper, the world's largest Ni-Cu-PGE sulfide deposit, Norilsk region in Russia, is studied as an example, introducing the spatial relationship between the gypsum layer and the distribution of the deposit, the distribution of sulfate minerals such as gypsum in the deposit and altered wall rocks, and the characteristics and variations of the ore-forming elements and sulfur isotope composition. The role of the gypsum layer in the mineralization has been explained with its ore controlling mechanism.The addition of gypsum layers (SO42-) can greatly improve the oxygen fugacity of the ore-forming system and oxidize Fe2+ into Fe3+ to form iron oxide. While the SO42- is reduced to provide reduced sulfur S2- into the ore-forming system, which makes the basic-ultrabasic ore-forming magma be changed from sulfide unsaturated to supersaturated. The small droplets of sulfide were formed and accumulated in the magma chamber, finally form magmatic liquation Ni-Cu-PGE sulfide deposit. In addition, sulfide-rich formations are also important sulfur source beds for the formation of Ni-Cu-PGE sulfide deposits.
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基金项目:本文得到业务费项目（编号：YYWF201710）和国家自然科学基金项目（编号：41973022、41627802）联合资助
引用文本：
李延河,段超,范昌福,胡斌,武晓珮.2020.膏盐层在Ni-Cu-PGE硫化物矿床成矿中的作用——以俄罗斯诺里尔斯克矿床为例[J].矿床地质,39(4):619~630LI YanHe,DUAN Chao,FAN ChangFu,HU Bin,WU XiaoPei.2020.Effect of gypsum layer for formation of Ni-Cu-PGE sulfide deposits: A case of Noril'sk ores, Russia[J].Mineral Deposits39(4):619~630
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