Nature of ore-fluids of intracontinental intrusion-related hypothermal deposits and its difference from those in island arcs.
Nature of ore-fluids of intracontinental intrusion-related hypothermal deposits and its difference from those in island arcs.
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发表时间：
2009
影响因子：
1.8
通讯作者：
Chen Yanjing;Li Nuo
中科院分区：
文献类型：
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作者：
Chen Yanjing;Li Nuo
本文总结了中国地区与侵入岩有关的60个低温热液矿床，包括通常命名的斑岩型、夕卡岩型、角砾岩管型、脉岩型和IOCG型。这些矿床形成于大陆造山带、断裂控制的岩浆带和活动的陆内造山带或克拉通边缘。这些矿床均表现出强烈的贫水围岩蚀变，如钾长石化、绿帘岩化、萤石化和碳酸盐化，而弱富水蚀变，如绢云母化、绿泥石化和黑云母化。流体包裹体数据表明，形成陆内侵入岩型低温矿床的成矿流体具有富CO_2、高盐度和高F、K含量的特点，与火山弧中常见的贫CO_2的氯化钠-水流体不同。结果表明，成矿流体和围岩蚀变的差异是由于成分来源不同造成的，即K/Na、F/Cl、CO2/H2O比值在陆壳高，洋壳低。
This paper summarizes 60 intrusion-related hypothermal deposits in China, including usually named porphyry, skarn, breccia pipe, vein and IOCG types. These deposits were formed and located in continental orogenic belts, fault-controlled magmatic belts and reactived intracontinental orogens or cratonic margins. All of these deposits display intense H_2O-poor wallrock alteration, such as K-feldspathization, epidotization, fluoritization and carbonation, and weak H_2O-rich alterations, such as sericitization, chloritization and biotitization. Fluid inclusion data indicate that the ore-fluids forming intracontinental intrusion-related hypothermal deposits are characterized by CO_2-rich and high salinity, together with high contents of F and K, contrasting to the CO_2-poor NaCl-H_2O fluids commonly observed in volcanic arcs. It is concluded that the differences in ore-fluid and wallrock alteration result from contrasting compositional sources, i. e. the ratios of K/Na, F/Cl and CO_2/H_2O are high in continental crust, whereas, low in oceanic crust.