摘要:与同一花岗质岩浆系统密切相关的不同成矿作用在成矿流体性质、组成、演化及成矿物质沉淀等特征既存在相似之处，也表现出明显差异。本文对赋存在社山复式岩体中的社垌石英脉型钨钼矿床和宝山斑岩型铜矿床进行的对比研究表明，钨钼矿体呈石英细脉状产出在社山加里东期黑云母花岗闪长岩中，铜矿体呈浸染状分布在宝山燕山晚期隐伏花岗斑岩体中。流体包裹体研究数据表明，社垌钨钼矿床石英中流体包裹体均一温度范围为180 ℃～320 ℃和340 ℃～440 ℃，其中主峰值范围为180 ℃～320 ℃，盐度峰值范围分别为0～10%、16%～20%、30%～34%，集中在0～10% NaClequiv.峰值范围内（n = 177），显示社垌钨钼矿床的成矿流体形成于一种中高温、中低盐度的H2O-NaCl±CO2体系。宝山斑岩型铜矿床中石英包裹体的均一温度范围在136.6 ℃～440.0 ℃，峰值为240 ℃～360 ℃，盐度主要集中在0.18%～34.83% NaClequiv.（n = 154），显示宝山斑岩型铜矿床的成矿流体属于中-高温、高盐度的NaCl-H2O-KCl±CO2体系。结合包裹体岩相学以及均一温度和盐度的特征，我们认为社垌脉状钨钼矿床成矿流体的演化经历了早期岩浆流体与晚期大气降水逐渐混合的过程，流体混合作用可能是引起矿石沉淀的主要因素，而宝山斑岩型铜矿床的成矿流体演化可能是早期岩浆结晶分异的中-高温、中-高盐度初始成矿流体，晚期又分异为高温、低盐度流体和高温、高盐度流体，流体沸腾和相分离作用对Cu金属元素的运移和沉淀起着重要的作用。
关键词: 大瑶山/
社垌W-Mo矿床/
宝山Cu矿床/
流体混合/
流体沸腾/
相分离作用
Abstract:The magmatic-hydrothermal metallogenic system may show similar evolution characteristics of the ore-forming fluids, which closely accompanied with the early magmatic evolution and with involvement of meteoric water in the late stage. However, the distinct mineralization associated with the same magmatic processes may also show difference in the characteristics, components and evolution of the ore-forming fluid, and precipitation mechanism of the ore-forming materials. In this paper, we studies the Shedong quartz-vein type W-Mo deposit and the Baoshan porphyry Cu deposit, which both hosted in the Sheshan composite pluton. The W-Mo ore bodies occurred in the Caledonian Sheshan biotite granodiorite with quartz veinlets while the Cu ore bodies show disseminated distributed in the Late Yanshanian concealed Baoshan porphyry granite. The fluid inclusion data of the Shedong W-Mo deposit show that the homogenization temperatures range from 180 ℃ to 320 ℃ and from 340 ℃ to 440 ℃. The main peak varies from 180 ℃ to 320 ℃. The peak salinity range from 0 to 10%, from 16% to 20%, and from 30% to 34% respectively, and centralizes in the range of 0 to 10% NaClequiv.（n = 177）, which indicates that the ore-forming fluid of the Shedong W-Mo deposit belongs to the H2O-NaCl±CO2 system with moderate-high temperature and moderate-low salinity. The homogenization temperatures fluid inclusions data in the Baoshan porphyry Cu deposit range from 136.6 ℃ to 440.0 ℃ and the peak is 240 ℃ to 360 ℃. The salinity centralizes in the range of 0.18% to 34.83% NaClequiv.（n = 154）, which indicates that the ore-forming fluid of the Baoshan Cu deposit belongs to the NaCl-H2O-KCl±CO2 system with mid-high to high temperature and high salinity. Thus, we can conclude that the evolution of the ore-forming fluid of the Shedong lode W-Mo deposit experienced the process of the gradual mixing of the early magmatic fluid and involvement of meteoric water in the late stage. The fluid mixing may be play an important role in the ore precipitation. The evolution of the ore-forming fluid of the Baoshan porphyry Cu deposit experienced the mid-high temperature initial fluid of early magma crystallization differentiation differs to high temperature, low salinity fluid and high temperature, high salinity fluid. Fluid boiling and phase separation play an important role in the migration and precipitation of metal elements.
Key words:Dayao Mountains/
Shedong tungsten-molybdenum deposit/
Baoshan copper deposit/
Fluid mixing/
Fluid boiling/
Phase separation
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