高温高压下C-O-H流体的研究

C O H流体是地球内部流体的主要组成部分 ,确定高温高压下它们的组成关系对于认识地球的演化、氧化还原环境以及促进包裹体的研究都具有重要的意义。高温高压实验确定了它们与石墨平衡存在一个间断温度 ,理论计算一般在此温度之上进行。当压力、温度确定时 ,再加上一个外部条件如fO2 或H/O比值 ,就可以得到它们的平衡组成。由于缺乏流体组分的高温高压热力学数据 ,目前的理论计算结果与实验值存在差别。电解质的出现和动力学因素影响着流体组分的平衡计算。加强系统研究 ,在实验中尽量采用就位分析的方法 ,获取更多更可靠的高温高压热力学数据 ,加强流体平衡影响因素的研究 ,是今后进一步的研究方向

STUDY OF C-O-H FLUIDS UNDER HIGH-TEMPERATURES AND HIGH-PRESSURES

C O H system is the most important fluid species in the interior of the Earth. Determination of its compositions at high pressure and high temperature is crucial for understanding the Earth evolution and its redox condition, and the research of fluid inclusion. There is a discontinuous temperature at equilibrium condition between graphite and the homogeneous C O H fluids measured by the high-pressure and high temperature experiment, and the discontinuous temperature is less than that deduced by the theoretical calculation. If the pressure, temperature, and another parameter such as the oxygen fugacity or the H/O atomic ratio of the fluid are known, the compositions of the C O H fluid can be calculated. Owing to the lack of thermodynamic data at high pressure and high temperature, there are still some deviations between the experimental data and the theoretical results. The factors such as the presence of salts in system and kinetic conditions have effect on the theoretical results. Thus, a lot of the high-pressure and high -temperature experiments should be carried out in the future, and the advanced in situ technique should be adopted, in order to acquire more reliable thermodynamic data at high-pressure and high-temperature, and strengthen the study on various factors affecting fluid equilibrium.