水对硅酸盐岩体系部分熔融行为的影响：第二临界端点的重要意义

水对硅酸盐岩体系的许多物理-化学行为有着非常重大的影响.具体对部分熔融过程来说,水可以显著地降低熔融温度、改变熔体性质、影响微量元素在固-液相之间的分配.近年来,科学家们就大量水对硅酸盐岩体系的部分熔融过程的影响进行了许多的高压实验,他们主要关注第二临界端点对熔融过程的重要作用:第二临界端点的出现极大地改变着部分熔融过程中的基本相关系.本文主要针对这些高压实验研究做一总结,并对未来研究方向做一初步探讨.

Effect of water on the partial melting process of some silicate systems: Important implication of the second critical endpoint

Water has substantial effects on many chemical-physical behaviors of the silicate systems. Specifically to the partial melting process, water can significantly depress the solidi, modify the melt properties, and change the partitioning patterns of trace elements between the melt and the solid phases. In recent years a large number of experimental studies at high pressures have been carried out to investigate the influence of large amounts of water on the partial melting process of the silicate systems, and special attention has been paid to the significance of the second critical endpoint which enormously changes the fundamental phase relationships of this process. Here we review these experimental studies in some wet silicate systems such as SiO_2 + H_2O, NaAlSi_3O_8 + H_2O, granite + H_2 O, basalt + H_2O and peridotite + H_2O, and tentatively outline the future directions.