水的相变:热液成矿作用的重要控制因素之一

The Phase Transition of Water:One of the Important Factors Controlling the Hydrothermal Mineralization

在热液成矿作用中,流体主要组分是水。在研究热液矿床时,除了要重视不同介质之间的化学反应和地质演化等因素外,水的相变也是了解热液成矿作用过程的关键。以热容为例,应用NIST(NationalInstituteofStandardsandTechnology)提供的网上计算平台,研究了地壳中随温压改变水的热容变化规律,指出相变可造成水的物理化学参数急剧变化、是热液成矿作用的必要条件,揭示出热液成矿作用中水的相变和断裂(或断裂+岩浆活动)之间的内在耦合关系。指出通过水的相变可建立成矿期次与断裂期次之间的对应关系,水的相变是热液矿床形成的重要控制因素之一。

Water is the main composition of the geo-fluid in the hydrothermal mineralization. The phase transition of water is also the key factor to understand the processes of hydrothermal mineralization,as well as the reactions among various substances and the geological evolutions. The paper, takes the isopressure heat capacity （Cp） for example of physicochemical properties, has studies the changing regularity of Cp according to temperature and pressure in the crust with the method from National Institute of Standards and Technology （NIST）and showed that the phase transition of water can cause the sharp variations of the physicochemical properties of water and is one of the essential factors to hydrothermal mineralization. From the study the paper has also revealed the interior coupling relations between the phase transitions of water and fracture or magma activities. Furthermore, the article suggests that the corresponding relations between fracture epoch and metallogenic epoch can be created by the aid of the water phase transitions and concludes the phase transition of water is the important factor to control the hydrothermal mineralization.