Simulation of dynamic interactions between earthquake ruptures and fluid migration in a fault zone

最近的实验室实验表明，断裂带中的流体对地震破裂的影响很大。在模拟中，我们通过流体力学模型参数的时空变化来研究流体迁移对余震发生的影响。首先对流体流量采用Forchheimer方程进行模拟，认为这是Darcy方程在动态范围内的推广。然而，流体流动方程的不同并不会导致显著不同的结果。因此，我们假设达西方程进行了余震发生的模拟。我们发现，通过考虑流体流动，可以统一地解释看似潜水的现象和复杂的余震现象。

Recent laboratory exoeriments suggest that fluids in a fault zone affect earthquake ruptures significantly. We here study the effects of fluid migration on aftershock occurrence through spatio-temporal changes in hydro-mechanical model parameters in our simulation. We first carried out the simulation assuming the Forchheimer equation for the fluid flow rate, which is regarded as an extension of the Darcy equation to dynamic range. However, the difference in the fluid flow equation does not give rise to significantly different results. We therefore carried out simulation of aftershock occurrence assuming the Darcy equation. We found that seemingly divers and complex aftershock phenomena can be explained in a unified way by the consideration of fluid flow.