Abstract: The rock dynamic mechanism is now overemphasied in the study of the mechanism for water radon anomalies as the precursor of earthquakes. This model suggests that the microfracturing of rock releases radon during the late period of earthquake pregnancy. A great deal of observations indicate, however, that water-radon anomalies can occur in the early time of earthquake pregnancy and wells far from epicentres, where rocks of water bearing layers can hardly be in the state of microfracture. So we propose the hydrodynamic mechanism for the water-radon anolmalies which suggests that the water-radon anolmalies can be casued by deformation of water-bearing rock mass and changes of its hydrodynamic state under the low stress level.

Key words: Radon in groundwater, Anomaly, Hydrodynamics

摘要： 在水氡异常机制研究中,人们以往都强调岩石力学机制,即孕震过程中岩石微破裂产生氡射气。然而,大量的震例表明,水氡异常可出现在孕震早期,可见于距震中较远的井中,那里的与那时的含水层岩石很难处在微破裂状态。因此,笔者提出水氡异常的水动力学机制,即在较低的应力水平下含水岩体的变形与其水动力状态的变化引起水氡异常的机制。

关键词: 水氡, 异常, 流体动力学