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巴布亚新几内亚波尔盖拉（Ｐｏｒｇｅｒａ）金矿床是世界级别的碱性浅成热液金矿体系（第Ⅱ阶段）的一个实例，同时它经过了岩浆热液金成矿的初始阶段（第Ⅰ阶段），通过这两个成矿阶段矿脉中流体包裹体的气体及离子色谱分析（ＧＣ和ＩＣ）可确定在成矿过程中流体的组分及其参与过程。这些数据资料显示了三种端元组分流体的存在，其中最稀释的一种贯穿了整个成矿过程，被认为是大气起源经过演化的地下水，它的成分包括５００ｍＭＮａ＋、１０ｍＭＫ＋、５ｍＭＬｉ＋、２５０ｍＭＣｌ－、０．１５ｍＭＢｒ－、０．０１ｍＭＩ－①，并具有一定浓度的溶解气体。而更多的是在两个主要的成矿阶段，极少部分是从岩浆流体中分离出来的高盐度流体。虽然组成不同，但它们就是金进入该系统的载体。第Ⅰ阶段矿物中所含流体包裹体盐分随与矿物伴生的终端组分的稀释程度逐渐减少，说明随岩浆流体来源加深逐渐被地下水稀释。虽然在原地流体混合作用也可能出现，但大部分由于简单的冷却作用或与围岩反应引起矿床沉积。含盐度最高的流体出现在早期石英和黄铁矿中，至少含有８１０ｍＭＮａ＋、５３０ｍＭＣａ＋２、１３０ｍＭＫ＋、１２ｍＭＬｉ＋、８７ｍＭＳＯ２－４、９６０ｍＭＣｌ－、１．１ｍＭＢｒ－和０．０５ｍ?
The Porgera gold deposit in Papua New Guinea is an example of a world class alkaline epithermal hydrothermal gold system (Stage II), which has undergone an initial phase of magmatic hydrothermal gold mineralization (stage I ), Gas and ion chromatographic analysis (GC and IC) of fluid inclusions in the veins can be used to determine the composition of the fluids and their participation in the mineralization process. These data show the presence of three end-member fluids, the thinnest of which runs through the entire mineralization process and is considered as the evolutionary groundwater of atmospheric origin. Its composition includes 500 mM Na +, 10 mM K +, 5 mM Li +, 250 mM Cl- , 0.15mMBr-, 0.01mMI-1, and has a certain concentration of dissolved gas. Mostly in the two main stages of mineralization, very few are high-salinity fluids that have been separated from magmatic fluids. Although different in composition, they are the carriers of gold into the system. The salt content of fluid inclusions contained in the first stage minerals gradually decreases with the dilution of the terminal components associated with minerals, which indicates that the fluid inclusions gradually dilute with groundwater as the source of magma fluid deepens. Although fluid mixing may occur in situ, most of the deposit is deposited due to simple cooling or reaction with surrounding rock. The fluids with the highest salinity appear in early quartz and pyrite with at least 810mMNa +, 530mMCa + 2,130mMK +, 12mMLi +, 87mMSO2-4,960mMCl-, 1.1mMBr- and 0.05m?