水的临界奇异性及其对热液铀成矿作用的意义  

The critical singularities of water and its significance in the hydrothermal mineralization of uranium

作　　者：胡宝群[1] 吕古贤[2] 王方正[3] 孙占学[1] 朱鹏[1] 

机构地区：[1]东华理工大学地球科学系,江西抚州344000 [2]中国地质科学院地质力学研究所,北京100081 [3]中国地质大学地球科学学院,湖北武汉430074

出　　处：《铀矿地质》2008年第3期129-136,共8页Uranium Geology

基　　金：国土资源部科技项目(2002201);江西省教育厅科技项目(2007230);东华理工大学博士启动基金项目

摘　　要：水是地质流体的主体,随着温压条件的变化会发生相变,许多物理化学性质也随之改变。特别是水具有临界奇异性,这对热液成矿作用有巨大的影响。本文介绍了水的相变种类及特征,研究了岩石圈中水可能存在的相变,以等压热容为例研究了水的临界奇异性,指出:(1)当温压同时趋近于临界常数时,水的临界奇异性最明显;(2)在岩石圈中温压受地温线控制,只有在热液作用、中酸性岩浆活动及断裂作用同时出现时,才可能使上地壳中某一区域同时达到温压的临界值;(3)对于热液成矿作用而言,水的临界奇异性的意义至少包括溶解度发生急剧变化和产生瞬时高压,这些变化可导致成矿物质沉淀和断裂的产生。Water is the main composition of the geo-fluid. With the changes of temperature and pressure, its phases and physicochemical properties will vary and the critical singularity occur at the critical point of second-order phase transition. These changes of water will enormously affect the hydrothermal mineralizations. This paper has introduced the types and characteristics of water phase transitions, studied the phase transitions of water in the lithosphere and showed the critical singularity of water with the example of the isobaric heat capacity. The conclusions are as follow： （1） the critical singularities of water are the most obvious as the temperature and pressure near to the critical constants of water; （2） Because the temperature changes with the pressure according to the thermal curve in the lithosphere, it is difficult to find a place where the temperature and pressure can be at the critical constants at same time except the coupling effect of the hydrothermal processes, intermediate-acidic magmatism and faulting; （3） To the hydrothermal mineralization, the significances of water＇s critical singularities at least include the sharp variation of solubility and instantaneous high pressure to conduct the deposit of ore-forming materials and fault formation.

关 键 词：水 相变 临界奇异性 热液成矿作用 

分 类 号：P619.1[天文地球—矿床学]