High Pressure Melting Relations of Model Carbonated Iherzolite in the CaO-MgO-Al2O3-SiO2-CO2 System: The Carbonatite-Kimberlite-Basalt Connection

CaO-MgO-Al2O3-SiO2-CO2 体系中模型碳化二辉橄榄岩的高压熔融关系：碳酸岩-金伯利岩-玄武岩连接

• 批准号: 9725900
• 负责人: Dean Presnall
• 金额: $ 36.18万
• 依托单位: University of Texas at Dallas
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-01-01 至 2002-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9725900&HistoricalAwards=false
• 关键词: Pressure; Melting; Relations; Model; Carbonated

9725900 Presnall Because partial melting processes in the mantle are generally understood to involve a close approach to fractional melting, it is important to obtain data on melt compositions at 2% melting. The low melt fraction limitation of studies on natural lherzolite can be overcome by using linear algebraic methods to extend the classical model system approach to systems of more than four components. This project will use this extended classical approach to study melting relations of model lherzolite in the CaO-MgO-Al2O3-SiO2-CO2 system in 3-5 GPa pressure range. All experiments will be done with a multianvil press and phase compositions will be determined with an electron microprobe. In this system, compositions of liquids produced by large to extremely small (0-2%) degrees of melting of lherzolite can be determined right down to the solidus by direct analysis, so that extrapolations from larger degrees of melting are unnecessary.

由于地幔中的部分熔融过程通常被理解为与部分熔融接近，因此获得2%熔融时熔体组成的数据很重要。利用线性代数方法将经典的模型体系方法推广到四组分以上的体系，可以克服天然二辉橄榄岩研究中熔体分数低的局限性。本项目将利用这一扩展的经典方法研究CaO-MgO-Al_2O_3-SiO_2-CO_2体系中模型二辉橄榄岩在3- 5GPa压力范围内的熔融关系。 所有的实验都将用多砧压机进行，相组成将用电子探针测定。在这个系统中，由二辉橄榄岩的大到极小（0-2%）的熔融度产生的液体的组成可以通过直接分析直接确定到固相线，因此不需要从更大的熔融度进行外推。