【摘要】 本项目通过对商用布鲁克Vertex 70v真空型红外光谱仪进行拓展,来构建一套水平红外光路的系统,并与红宝石测压系统、外加温温控系统联用,适用于高压、高/低温测量的傅立叶变换红外显微系统,从而真正实现在原位条件下观察与研究地球内部物质的性质和结构特征的实验平台。在此平台上,模拟并观察在俯冲带中不同深度(温压)环境下的绿帘石红外光谱特征,同时结合拉曼光谱特征,了解晶体结构和晶体化学的稳定性、水溶解度、高压化学和高压物理学现象,从而窥视洋壳/陆壳俯冲全过程中矿物物理化学性质及其水循环的动力学演化。更多还原

【Abstract】 This project is to develop a custom in-situ infrared( IR) microscope for high-pressure and high/low temperature FT-IR studies on Bruker Vertex 70 v vacuum FT-IR spectrometer. This microscope system is specially designed with horizontal IR beam together with a ruby pressure calibration system and a temperature control system of external heater,an ideal platform for in-situ highpressure and high/low temperature IR spectroscopic research on the properties and structures of the materials in the deep interiors of planets. High pressure and temperature IR spectra of epidote were obtained with this experimental platform to simulate and investigate its structure and water solubility under condition of the different temperature and pressure during subduction,together with mineral chemical characteristics and Raman data,to look insight into the dynamic evolution of mineral’s physicochemical property and water cycle in the whole process of subduction. The data of epidote on IR spectroscopic and Raman spectroscopic research in-situ under highpressure and high temperature show that the structure of the epidote remained stable,while temperature increasing from room temperature to 873 K,pressure from 0. 1 GPa to 11. 87 GPa. In particular,the M-O bond with weak compressibility of the epidote is related to the substitution of Fe-Al on the octahedron. OH vibration spectrums in infrared spectrum are sudden increase and disappearance,which maybe related to redox of Fe. Our results demonstrate that epidotite can be stable at least within the range of P =11. 87 ～ 12. 73 GPa and T = 773 ～ 873 K. Therefore,epidotite,as hydrous mineral,could have carried water into the mantle.更多还原