北京高压科学研究中心高温高压下水镁石[Mg(OH)₂]的稳定性和反应数据集（2020-2021）

水镁石是典型的水合矿物。本研究通过电阻外加热金刚石压砧（DAC）实验，在15.4 GPa高压和874 K高温条件下开展拉曼光谱测量，揭示了水镁石在俯冲板块相关环境中的稳定性特征。研究表明，当水镁石与碳酸氢根离子反应生成菱镁矿（MgCO3）时，会释放水分。这一过程表明，地球内部的水循环与深部碳循环存在深度耦合。样品合成和原位高压拉曼光谱测试在北京高压科学研究中心完成。使用外电阻加热DAC技术进行高温高压实验，使用铂丝为加热源，K型热电偶为测温传感器和Scistar-TC-1000温度控制器。原位高压拉曼光谱使用Renishaw Raman microscope系统，激光波长采用532 nm，使用高纯氩气（Ar）作为静水压介质（PTM）可减少体系压差。本课题通过研究水镁石的稳定性和反应性可以用于通过量化反应计算俯冲板片在下沉过程中，能将多少地表碳（以碳酸盐形式）通过该反应固定为稳定的镁碳酸盐矿物，并带入地幔深部推导深部流体的实际化学状态。

Brucite is a typical hydrous mineral. In this study, in-situ Raman spectroscopic measurements were conducted using externally resistively heated diamond anvil cell (DAC) experiments under 15.4 GPa high pressure and 874 K high temperature, revealing the stability characteristics of brucite in subduction zone-related environments. The results show that when brucite reacts with bicarbonate ions to form magnesite (MgCO₃), water is released. This process demonstrates that the Earth's internal water cycle is deeply coupled with the deep carbon cycle. Sample synthesis and in-situ high-pressure Raman spectroscopic measurements were completed at the Beijing Research Center for High Pressure Science. High-pressure and high-temperature experiments were carried out using the externally resistively heated DAC technique, with platinum wire as the heating source, K-type thermocouple as the temperature measurement sensor, and the Scistar-TC-1000 temperature controller. The in-situ high-pressure Raman spectroscopic measurements were performed using a Renishaw Raman microscope system, with a laser wavelength of 532 nm. High-purity argon (Ar) was used as the pressure-transmitting medium (PTM) to reduce the pressure differential within the system. By investigating the stability and reactivity of brucite, this study can quantify the amount of surface carbon in the form of carbonates that can be fixed into stable magnesium carbonate minerals via this reaction during the descent of subducting slabs, thereby transporting the fixed carbon into the deep mantle and deducing the actual chemical state of deep fluids.

搜集汇总

背景与挑战

背景概述

该数据集聚焦于水镁石[Mg(OH)₂]在高温高压条件下的稳定性和反应性研究，通过金刚石压砧实验在15.4 GPa和874 K下进行拉曼光谱测量，揭示了水镁石与碳酸氢根离子反应生成菱镁矿并释放水分的过程，关联了地球深部水循环与碳循环的耦合。数据以Excel文件格式存储，涵盖2020年至2021年的实验数据，适用于量化俯冲板片碳固定过程的研究。