Experimental Investigation of Mineral-Fluid Equilibria at High Pressure

高压矿物流体平衡的实验研究

• 批准号: 0337170
• 负责人: Craig Manning
• 金额: --
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-01-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0337170&HistoricalAwards=false
• 关键词: Experimental; Investigation; Mineral; Fluid; Equilibria

ManningEAR-0337170Water-rich fluids are common in the deep crust and upper mantle. Because mineral solubilities are high in these environments, liberation and migration of such fluids causes significant mass transfer. Fluids generated by subducting lithosphere transfer solutes from the slab and therefore play a fundamental role in mediating chemical cycling in the Earth. Xenolith suites show that significant regions of the upper mantle may be modified by passage of H2O-CO2-NaCl fluids. During crustal metamorphism, solute-rich fluids may play a crucial role in the redistributing matter. Quantitative understanding of the processes by which fluids transport material requires accurate knowledge of mineral solubility. At high pressures (5 kbar), experimental challenges have previously limited the availability of key data; however, new techniques now make it possible to carry out studies on important model systems.This project involves three sets of experimental studies of aimed at better understanding high-pressure mineral-fluid equilibria: (1) studies of silica-polymer formation over a broad range of pressure and temperature; (2) experiments on the changes in solute chemistry associated with the second critical end-point in the system albite-water; and (3) characterization of the solubility of the volatile-bearing phases calcite and anhydrite.The intellectual merit of the proposed investigation will be quantitative constraints on the chemistry of aqueous species at high pressure, where existing data are limited. Such data are critical for understanding how fluids participate in the material cycling in the Earth. Broader impacts will include student training and mentoring. The proposed experiments on albite- paragonite-quartz are a component of Ph.D. studies of A. Antingano. The PI has also included undergraduates from diverse backgrounds in petrologic research at UCLA, resulting in published abstracts at professional meetings.

富含水的流体在地壳深处和上地幔中很常见。由于这些环境中矿物的溶解度很高，这些流体的释放和迁移导致了显著的传质。俯冲岩石圈产生的流体从板块转移溶质，因此在调节地球化学循环中起着基本作用。捕虏体套件表明，上地幔的重要区域可能被H2O-CO2-NaCl流体的通过所修饰。在地壳变质过程中，富溶质流体对物质的再分配起着至关重要的作用。定量了解流体输送物质的过程需要对矿物溶解度有准确的了解。在高压下（5kbar），实验方面的挑战限制了关键数据的可用性；然而，现在的新技术使得对重要的模型系统进行研究成为可能。该项目包括三组旨在更好地理解高压矿物-流体平衡的实验研究：(1)在广泛的压力和温度范围内研究二氧化硅-聚合物形成；(2)钠长石-水体系中第二个临界终点溶质化学变化的实验；(3)含挥发物相方解石和硬石膏的溶解度表征。在现有数据有限的情况下，所提议的调查的智力价值将是对高压下含水物质化学的定量限制。这些数据对于理解流体如何参与地球上的物质循环至关重要。更广泛的影响将包括学生培训和指导。拟进行的钠长石- paragonite-石英实验是a . Antingano博士研究的一个组成部分。PI还包括来自加州大学洛杉矶分校岩石学研究不同背景的本科生，他们的论文摘要在专业会议上发表。