Elasticity of High Pressure Mantle Garnet Phases at High Pressures and High Temperatures

Gwanmesia 0106528本研究是为了精确测量镁铝硅氧体石榴石在高压和高温下的声波速度(P-Vp-vs-T测量)和状态方程(P-V-T关系)。实验将在安装在布鲁克海文国家实验室国家同步辐射光源超导摇摆器束线(X17B1)上的立方顶锤DIA型高压装置SAM-85中进行。高压和高温弹性数据，以及状态方程数据，将与用单晶或多晶样品通过其他弹性技术获得的镁铝硅钙铝榴石的数据进行比较。这项研究将利用现有的镁铝硅氧石多晶样品和其他新的样品，在2000吨的单轴分裂球体装置(USSA-2000)中，在高达5 Gpa和1350℃的条件下进行热压。样品将通过X射线衍射、光学、扫描和透射电子显微镜以及台式超声波技术进行表征，以确保样品是单相、细晶和无气孔和裂纹的。

Gwanmesia 0106528 The study is to make precise measurement of the acoustic wave velocities at simultaneous high-pressures and temperatures (P-Vp-Vs-T measurements) and the equation of state (P-V-T relations) for Mg3Al2Si3O12-pyrope garnet. The experiments will be conducted in a cubic anvil DIA-type high pressure apparatus, SAM-85, which is installed on the super conducting wiggler beam line (X17B1) at the National Synchrotron Light Source of the Brookhaven National laboratory. The high pressure and high temperature elasticity data, as well as the equation of state data, will be compared with data for Mg3Al2Si3O12-pyrope garnet obtained by other elasticity techniques using single-crystal or polycrystalline specimens. The study will utilize existing polycrystalline specimens of Mg3Al2Si3O12-pyrope garnet and other new specimens hot-pressed in a 2000-ton uniaxial split-sphere apparatus (USSA-2000) at conditions up to 5 GPa, and 1350C. Samples will be characterized by x-ray diffraction, optical, scanning and transmission electron microscopy and by bench top ultrasonic techniques, to ensure that the specimens are singled-phase, fine-grained and pore- and crack-free.