辽宁清原南龙王庙金矿流体包裹体研究

南龙王庙金矿位于华北克拉通北缘，产在清原群表壳岩的北东端.主要容矿岩石为新太古代的磁铁石英岩，控矿构造为葫芦头沟-大荒沟韧性剪切带.矿石以细脉-浸染状构造为主.主要蚀变类型有白云母化、硅化、绿泥石化、碳酸盐化和绿帘石化.对矿区细脉-浸染状矿石石英中的流体包裹体进行了系统的岩相学、显微测温分析.结果显示，矿石石英中存在两个不同阶段的流体包裹体：早阶段形成的包裹体主要为含子矿物的三相包裹体（I）；晚阶段形成的包裹体包括气液两相包裹体（II）、纯CO₂包裹体（III）和含CO₂三相包裹体（IV）三种类型.流体演化过程为：早阶段的中温、高盐度、中等密度的流体，萃取清原群表壳岩中的Au；晚阶段在剪切带韧性变形向脆性变形转化过程中，流体演化为中温、中低盐度、低密度的特征，Au成矿元素达到饱和，在有利的构造空间沉淀成矿.成矿作用的方式由早期的扩散交代逐渐转变为晚期的充填作用，分别形成细脉-浸染状矿体和含金黄铁矿石英脉型矿体.

STUDY ON THE FLUID INCLUSIONS OF NANLONGWANGMIAO GOLD DEPOSIT IN QINGYUAN,LIAONING PROVINCE

The Nanlongwangmiao gold deposit is occurred in the northeast of Qingyuan Group supracrustal rocks in the northern margin of North China Craton. The main host rock is Neoarchean magnetite quartzite with Hulutougou-Dahanggou ductile shear zone as the ore-controlling structure. The ore is veinlet-disseminated structure dominated with the main alteration types of muscovitization, silicification, chloritization, carbonatization and epidotization. The analysis results on the petrography and microthermometry of fluid inclusions in the veinlet-disseminated quartz ore show that there are two stages of fluid inclusions. The early stage forms the daughter mineral-bearing three phrase inclusions (I); while the later stage involves the gas-liquid inclusions (II), pure CO₂ inclusions (III) and CO₂-bearing three phase inclusions(IV). The course of fluid evolution is as follows:The early-stage fluids with medium temperature, high salinity and intermediate density extract Au from the supracrustal rocks of Qingyuan Group, and then turn into moderate-low salinity and low density during the transformation of shear zone from ductile to brittle deformation at the later stage. The Au element reaches saturation and precipitates in favorable structural space to form deposit. The mineralization gradually changes from diffusion metasomatism to filling, forming veinlet-disseminated and gold-bearing pyrite quartz-vein orebodies respectively.