Monazite as a Thermochronometer for Prograde Metamorphism

9316166哈里森这个项目提出的实验，将导致更好地了解独居石作为一个thermochronometer。 独居石被选中进行研究，因为它的保留性质的Pb* 和其不寻常的（辅助矿物）的行为在成岩作用表明，它的使用作为一个系统，能够连续记录热年代学信息的泥质岩的变质过程中。 三个不同的，但最终相互关联的，研究需要利用这一观察：独居石的U-Th-Pb微量分析的发展，泥质组合中的LREE氧化物的稳定性和反应动力学，以及独居石中的Pb扩散。 这些研究将导致利用的Th-Pb系统的日期离散的反应事件在造山带的加热阶段，以及一个完善的知识的封闭温度为铅在独居石。

9316166 Harrison This project proposes experiments that will lead to a better understanding of monazite as a thermochronometer. Monazite was selected for study because its retentive nature for Pb* and its unusual (for an accessory mineral) behavior during diagenesis suggests its use as a system capable of continuously recording thermochronological information during prograde metamorphism of a pelite. Three distinct, but ultimately interconnected, studies are required to exploit this observation: development of U-Th-Pb microanalysis for monazite, the stability and reaction kinetics of LREE oxides in pelitic assemblages, and Pb diffusion in monazite. These studies will lead to utilization of the Th-Pb system to date discrete reaction events in the heating phase of orogenic terranes as well as a refined knowledge of the closure temperature for Pb in monazie.