Accomplishment-Based Renewal: Experimental Determination of the PVTX and Phase Equilibrium Properties of Aqueous Chloride Fluids at Magmatic-hydrothermal Conditions

世界人口不断增加，再加上全球生活水平的全面提高，需要越来越多的资源来满足人类的需求。地球是制造维持现代技术社会所需产品所需的所有矿物、金属和其他自然资源的来源。旨在发现矿物和金属新产状的勘探模式是基于对导致金属和其他资源积累成经济集中的各种物理、化学和生物过程的了解。大多数矿产和金属矿床是在地壳中加热的流体溶解、输送和沉积金属形成矿床时形成的，大多数成矿流体是含有各种盐类的高盐度卤水。该项目的目标是更好地了解在适合成矿系统的温度和压力条件下盐水流体的基本性质。这些信息反过来将导致开发更好的矿产勘探模式，并有助于经济稳定和繁荣，并通过减少对外部来源的依赖来促进更安全的未来，以提供技术和国防应用所需的原材料。该项目还将为来自不同背景的几名学生和年轻研究人员提供最先进的实验和分析技术培训。地壳中的大多数天然咸水流体近似于H2O-NaCl-KCl2-CaCl2-FeCl2体系。以前的工作表明，盐水流体在高温和压力下的物理和化学行为高度依赖于流体的总盐度以及流体中各种主要盐组分的比例。在本项目中，将进行实验以确定岩浆-热液相变条件下氯化物水溶液的压力-体积-温度组成(PVTX)和相平衡性质。在岩浆-热液PTX条件下，合成流体包裹体将被捕获，该包裹体含有不同二元、三元、四元和五元组分的流体。相边界(气-液曲线和液体)、临界点和等轴线(密度恒定的线)将使用合成流体包裹体技术确定，该技术已在许多早期研究中被证明是成功的。将从实验数据中开发出基于对天然流体包裹体的显微测温和微量分析来估计各子系统中流体成分的经验数值配方。这些数据为解释天然流体包裹体的微温数据提供了基础，并为今后的研究提供了素材，以开发描述适用于地壳热液系统的PTX条件范围内热液PVTX性质的经验数值模型。该项目的研究结果将有助于更好地理解REAL？REAL？岩浆-热液流体，并为根据自然系统中流体包裹体研究获得的数据开发更可靠的矿产勘探模型提供了坚实的基础。

Increasing world population, combined with an overall increase in global standard of living, requires an ever-increasing amount of resources to meet human demands. The Earth is the source of all the minerals, metals and other natural resources required to manufacture the products needed to sustain a modern technological society. Exploration models designed to discover new occurrences of minerals and metals are based on an understanding of the various physical, chemical and biological processes that lead to the accumulation of metals and other resources into economic concentrations. Most mineral and metal deposits are formed when heated fluids in the Earth's crust dissolve, transport and deposit metals to form ore deposits, and most of the ore-forming fluids are highly-saline brines containing various salts. The goal of this project is to develop a better understanding of the fundamental properties of saline fluids at temperature and pressure conditions appropriate for ore-forming systems. This information, in turn, will lead to development of better mineral exploration models and contribute to economic stability and prosperity and promote a more secure future by reducing dependence on external sources to provide the raw materials needed for technological and defense applications. The project will also provide training in state-of-the-art experimental and analytical techniques for several students and young researchers from diverse backgrounds. Most natural saline fluids in the Earth's crust are approximated by the H2O-NaCl-KCl-CaCl2-FeCl2 system. Previous work has shown that the physical and chemical behavior of saline fluids at elevated temperatures and pressures is highly dependent on the total salinity of the fluid as well as the ratios of the various major salt components in the fluid. In this project experiments will be conducted to determine the Pressure-Volume-Temperature-Composition (PVTX) and phase equilibrium properties of aqueous chloride fluids at magmatic-hydrothermal PTX conditions. Synthetic fluid inclusions containing fluids with various binary, ternary, quaternary and quinary compositions within this five-component system will be trapped at magmatic-hydrothermal PTX conditions. Phase boundaries (liquid-vapor curves and liquidi), critical points, and isochores (lines of constant density) will be determined using the synthetic fluid inclusion technique that has proven to be successful in numerous earlier studies. Empirical numerical recipes to estimate compositions of fluids in the various sub-systems based on microthermometric and microanalysis of natural fluid inclusions will be developed from the experimental data. These data provide the basis for interpretations of microthermometric data from natural fluid inclusions and provide feedstock for future studies to develop empirical numerical models describing the PVTX properties of hydrothermal fluids over the range of PTX conditions appropriate for crustal hydrothermal systems. The results of this project will lead to a better understanding of the phase equilibrium and PVTX behavior of ?real? magmatic-hydrothermal fluids, and provide a solid basis for developing more robust mineral exploration models based on data obtained from studies of fluid inclusions in natural systems.