An Experimental Study of Solubility, Solution Mechanisms, and Stable Istope Fractionation of COHN Volatiles in Silicate Melts and Fluids in the Earth's Interior

地球内部硅酸盐熔体和流体中 COHN 挥发物的溶解度、溶解机理和稳定同位素分馏的实验研究

• 批准号: 0734182
• 负责人: Bjorn Mysen
• 金额: $ 6.39万
• 依托单位: Carnegie Institution of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-01 至 2013-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0734182&HistoricalAwards=false
• 关键词: Experimental; Study; Solubility; Solution; Mechanisms

Intellectual merit. Characterization of the processes that govern the behavior and budget of volatiles (H2O, CO2, CO, CH4, N2, NH3, noble gases, etc.) in the Earth's interior is fundamental to our understanding of the formation and evolution of the solid Earth, its oceans, and atmosphere. Physicochemical description of melting and crystallization in the Earth's interior is central to this understanding. Experimental characterization of solubility and solution mechanisms of volatiles in silicate melts, and the distribution and stable isotope fractionation of volatile components between condensed and gaseous phases are important components of this knowledge base and form the core of the proposed research. A research program is proposed to experimentally determine (i) the solubility and solution mechanisms in silicate melts of volatiles in the C-H-O-N system as a function of bulk composition, temperature, pressure, and redox conditions with particular emphasis on reduced species, and (ii) isotope fractionation between nitrogen and carbon dissolved in silicate melts and in coexisting gas at mantle pressures and temperatures as a function of speciation of the volatiles in melt and coexisting gas. Preliminary experimental data suggest that this work will have profound implications for core-formation, the Earth's evolution, volatile budget, and degassing processes. The proposed work will provide information on melt structure of simple silicate melt systems with expansions to more complex chemical systems (including Fe-bearing) as needed. These properties will be determined as a function of composition, pressure, temperature, and hydrogen fugacity. Structural studies will be conducted via Raman, Mossbauer, and FTIR spectroscopy. Chemical and isotopic analyses of melts and coexisting gas will be carried out with the electron microprobe, gas chromatography, and mass spectrometry.Broader impacts. In addition to the PI proposed research program will involve on the average 1-2 post-doctoral researchers and 2 undergraduate and high school interns during the 3-year period of the proposed research. The students and post-docs will be involved in execution of experimental projects and in the application of the experimental results to characterization of rock-forming processes. They will, therefore, aid in reaching the goals of the proposed research. In addition, continuing international collaboration between the PI and researchers from the Institute for the Study of the Earth's Interior (ISEI, Misasa, JAPAN) and Institut de Physique du Globe (Paris, FRANCE) will further aid the proposed research program. In particular, collaboration between researchers at the Geophysical Laboratory and at ISEI will be central to the successful completion of the proposed project.

智力上的优点。 表征控制挥发物（H2O、CO2、CO、CH 4、N2、NH3、惰性气体等）行为和预算的过程对我们理解固体地球、海洋和大气层的形成和演化至关重要。地球内部熔化和结晶的物理化学描述是理解这一点的核心。硅酸盐熔体中挥发物的溶解度和溶解机制的实验表征，以及冷凝相和气相之间挥发性组分的分布和稳定同位素分馏是该知识库的重要组成部分，并形成拟议研究的核心。提出了一个研究计划，以实验确定（i）作为本体组成，温度，压力和氧化还原条件的函数的C-H-O-N系统中的挥发分在硅酸盐熔体中的溶解度和溶解机制，特别强调还原物种，以及（ii）在地幔压力和温度下，溶解在硅酸盐熔体和共存气体中的氮和碳之间的同位素分馏是熔体和共存气体中挥发分的形态。初步的实验数据表明，这项工作将有深远的影响，核心的形成，地球的演变，挥发性预算，和脱气过程。拟议的工作将提供简单的硅酸盐熔体系统的熔体结构与扩展到更复杂的化学系统（包括铁轴承）所需的信息。这些性质将被确定为组成，压力，温度和氢逸度的函数。将通过拉曼、穆斯堡尔和FTIR光谱进行结构研究。将用电子探针、气相色谱和质谱对熔体和共存气体进行化学和同位素分析。除了PI提出的研究计划将涉及平均1-2博士后研究人员和2名本科生和高中实习生在3年的拟议研究期间。学生和博士后将参与实验项目的执行，并将实验结果应用于岩石形成过程的表征。因此，它们将有助于实现拟议研究的目标。此外，PI与来自地球内部研究所（ISEI，Misasa，日本）和地球仪研究所（巴黎，法国）的研究人员之间的持续国际合作将进一步帮助拟议的研究计划。特别是，地球物理实验室和国际空间研究所的研究人员之间的合作将是成功完成拟议项目的关键。