变质流体对变质反应温度缓冲作用实例研究及意义

有关闽北麻源群、浙西南陈蔡群、冀东麻粒岩和冀西南阜平群变质流体与变质反应温度关系实例研究表明，在变质作用过程中，变质流体对变质反应温度存在着明显的缓冲效应，缓冲的温度范围可超过某些变质相或变质带之间的温度差。因此，变质流体同变质温度、压力一样，是划分变质相带一个独立参数。本文从热力学理论上解释了变质流体对变质反应温度缓冲作用的机制，并对缓冲强度进行了估算，据此阐述了变质流体在变质相带研究中的重要意义。

THE STUDIED EXAMPLES AND THEIR IMPLICATIONS OF BUFFERING OF METAMORPHIC REACTION TEMPERATURE BY METAMORPHIC FLUIDS

The studies on buffering of metamorphic reaction temperature by metamorphic fluids from Mayuan Group in northern Fujian Province,Chencai Group in southeastern Zhejiang Province,granulites in eastern Hebei Province and Fuping Group in southwestern Hebei Province show that the obvious buffering exists between metamorphic fluids and metamorphic reaction temperature,and the buffered temperature range sometimes exceeds the temperature differences between some metamorphic facies and between metamorphic zones.Metamorphic fluids,therefore,should be regarded as an independent variable during metamorphic processes.The paper explains the mechanism of buffering of metamorphic reaction temperature by metamorphic fluids, evaluates the buffering degree of temperature from thermodynamical theory,and discusses the significance of metamorphic fluids in the studies of metamorphic facies and zones.