Trace Element Distribution Within, Between, and Among Metamorphic Minerals

该建议是开发微量元素分区作为一种工具，以帮助岩石学家破译一个岩石的变质历史的任务，并应用此工具，以进一步我们对地球历史的理解。将对经历过部分熔融（深熔）的变岩和经历过高P/T变质作用的岩石进行详细研究，以充分表征主相和副相的微量元素分带和分配。 独居石-磷钇矿温度计的经验校准将得到增强和提高，包括HREE，Th和U对独居石YPO 4含量的影响，以及为应用该温度计而开发的程序，以产生有意义的结果。 另外两个温度计，YAG-磷钇矿和YAG-独居石，也将同样得到改进，以便它们适用于各种条件。将探索基于钇在高压下在石榴石和辅助矿物之间分配的其他新的经验温度计。将开发全岩反应和矿物成分变化的热力学模型，以将辅助矿物共生建立在坚实的理论基础上。该模型将用于预测主要相反应中副矿物的参与，并解释在研究套件中观察到的天然共生体。

SpearEAR-0106738 This proposal is to develop trace element partitioning as a tool to assist petrologists in the task of deciphering the metamorphic history of a terrane, and to apply this tool to further our understanding of Earth history. Detailed studies will be carried out on metapelites that have undergone partial melting (anatexis) and rocks that have undergone high P/T metamorphism in order to characterize fully the trace element zoning and partitioning in major and accessory phases. An empirical calibration of a monazite-xenotime thermometer will be augmented and enhanced to include the influence of HREE, Th and U on monazite YPO4 content, and procedures developed for the application of this thermometer to yield meaningful results. Two additional thermometers, YAG-xenotime and YAG-monazite, will be similarly enhanced so that they are applicable over a wide range of conditions. Additional new, empirical thermometers based on yttrium partitioning between garnet and accessory minerals at high pressures will be explored Thermodynamic models of whole rock reactions and mineral composition variation will be developed to place accessory mineral paragenesis on a firm theoretical footing. The models will be used to make predictions about the involvement of accessory minerals in major phase reactions, and in the interpretation of natural parageneses observed in the study suites.