The High Pressure Structure of Silicate Liquids: Constraints on the Chemical and Physical Properties of Deep Earth Melts

该项目涉及收集关于高压和高温下硅酸盐模拟液体的结构和电传输特性的信息，以及关于在高压和高温下形成的仅在温度下淬火的玻璃的结构的信息。主要的结构探针是振动光谱：主要是液体的拉曼光谱，以及在高压下原位保持的红外光谱或淬火玻璃。该计划是利用外部加热的钻石电池来产生压力和温度，用于液体的光谱和电导实验，并将激光加热与钻石砧座电池耦合以形成高压玻璃。这些数据对预测和评估压缩下岩浆液体的密度和粘度等物理性质的变化至关重要，并从根本上影响地球分化到目前状态的过程。其目标是为高压下硅酸盐熔体的地球化学性质、热力学性质和输运性质的变化提供结构基础。由于最近在产生和校准金刚石顶锤单元内的高压和温度方面取得的进展，以及固态探测器技术的进步，这些试验已经成为可能。

This project involves collecting information on the structure and electrical transport properties of silicates-analogue liquids at high pressures and temperatures and on the structures of glasses formed at high pressures and temperatures and quenched only in temperature. The primary structural probes are vibrational spectroscopy: principally Raman spectroscopy for the liquids, and infrared spectroscopy or quenched glasses held in situ at high pressures. The plan is to utilize the externally heated diamond cell to generate pressure and temperature for both spectroscopic and conductivity experiments on liquids, and laser heating coupled with the diamond anvil cell to form high pressure glasses. Such data are critically important in predicting and evaluating changes in the physical properties, such as density and viscosity, of magmatic liquids under compression, and bear fundamentally on the processes by which the Earth has differentiated to its present state. The goals is to provide a structural basis for changes in the geochemical, thermodynamics, and transport properties of silicate melts at high pressures. These experiments have been rendered feasible by recent advancements in both the generation and calibration of high pressures and temperatures within the diamond anvil cell, as well as advances in solid-state detector technology.