地下水在地震前兆应力场演化过程中的作用

The roles of groundwater in the evolution process of seismic precursor stress field

采用应力场与渗流场耦合的三维数值模拟方法 ,通过干模型和湿模型的对比 ,研究了地下水在地震前兆应力场演化过程中的作用。研究结果表明 ,地下水的存在 ,不单增加了前兆应力场时空演化的流变性 ,并促使应力向断裂带聚集 ,而且还增加了震前的破裂水平。尤其是在短临阶段 ,这种作用更加显著 ,但随深度的增加 。

Through comparison of dry model and wet model, the roles of groundwater in the process of time space evolution of seismic precursor stress field before the earthquake are studied by means of three dimensional modeling. The results show that the presence of groundwater will not only enhance the rheological property of the time space evolution of precursor stress field, make the stress concentrate on the fault zones, but improve enhance the fracture level, especially at the short imminent stage, it often becomes remarkable. However, as the depth goes deeper, the mechanical effects of groundwater on the distribution of stress field drops gradually.