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

由于地幔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%熔融时熔体成分的数据是很重要的。利用线性代数方法将经典的模型系统方法扩展到四组分以上的系统，可以克服天然橄榄岩研究的低熔体分数限制。本项目将利用这一扩展的经典方法，研究3-5 GPa压力范围内CaO-MgO-Al2O3-SiO2-CO2体系中模式辉沸石的熔融关系。所有的实验都将用多砧压机完成，相组成将用电子探针确定。在这个系统中，由大到极小（0-2%）的沸石熔融度产生的液体组成可以通过直接分析确定，直至固体，因此无需从较大的熔融度进行外推。

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.