BEHAVIOR OF METALS DURING FORMATION OF BASE METAL DEPOSITS

从含水岩浆中分离出来的岩浆流体盐度高，含有重金属和CO_2等气体成分。岩浆流体被认为是热液矿床的形成原因。在液体沸腾过程中，溶解在液体中的挥发性成分进入气相，而盐和金属保持在液体中。然而，与高温热液系统有关的富气流体包裹体中偶尔会发现高浓度的金属。这种蒸气包裹体表明，金属在沸腾水热系统中的行为比人们所认为的要复杂得多。为了弄清金属在沸腾过程中的行为，本研究介绍了新设计的高温高压灭菌器。为了分析沸腾条件下合成的流体包裹体中铜和锌的浓度，测定了铜和锌在共存的气相和液相之间的分馏。我们的结果表明，在自然高温热液体系附近偶尔发现的高浓度铜可能以硫化物络合物的形式溶解。本文利用同步辐射X射线荧光技术对单个流体包裹体进行了分析。这一方法的量化是为了利用已知金属浓度的合成流体包裹体来弥补校正线。本文还对氯化钠-二氧化碳-水体系中氯化钠的溶解度进行了水热实验。研究了智利安第斯地区曼陀型铜矿床成矿流体的来源和性质，以及与接触变质层状锰矿床有关的变质水成矿流体的来源和性质。

Magmatic fluid separated from hydrous magma has high salinity, and contains heavy metals and gaseous components such as CO_2. Magmatic fluids are believed to be responsible for the formation of hydrothermal ore deposits. Volatile components dissolved in fluid move into vapor phase, while salts and metals remain in liquid phase during boiling of fluids. However, metals of high concentration are occasionally found in vapor-rich fluid inclusion associated with high temperature hydrothermal system. Such vapor inclusions suggest that the behavior of metals under boiling hydrothermal system is more complex than it has been believed. In order to clarify the behavior of metals during boiling, newly designed high temperature autoclave was introduced in this study. Fractionation of Cu and Zn between coexisting vapor and liquid phases was determined to analyze concentration of these metals in fluid inclusions synthesized under boiling condition. Our result suggests that high concentration of copper occasionally found in vicinity of natural high temperature hydrothermal system is probably dissolved as sulfide complex. Synchrotron X-ray fluorescence was used as a technique to analyze individual fluid inclusion in present study. The quantification of this methodology was established to make up correction lines using synthetic fluid inclusions of known concentrations of metals. Hydrothermal experiments on the solubility of NaCl in the system NaCl-CO_2-H_2O were also conducted. Studies on the origin and nature of ore-forming fluid of the manto-type Cu deposit at the Andes area, Chile, and those of metamorphic water associated with contact metamorphosed bedded manganese deposit were conducted.