Numerical Simulation of Fluid Pore Pressure Diffusion and Its Mechanical Effects during Wenchuan Aftershocks

The Ms 8.0 Wenchuan earthquake occurred on 12 May 2008, in the Sichuan Province of China, and it was accompanied by a series strong aftershocks. mechanisms contributing to triggering aftershocks have attracted international attention. In this paper, based previous analysis spatiotemporal distribution regarding pore pressure diffusion deep fluid, we established three-dimensional hydraulic–mechanical coupling model investigated influence fluid migration its mechanical effects Longmenshan fault zone using FLAC3D software. We obtained characteristics reactivation within 70 days an area NA. results show that significantly increases up 80 MPa during intrusion into plane. increase along dip is greater than strike, with maximum difference 3.18 MPa. reduces effective stress leads reactivation. evolution calculated compared This study meaningful for furthering understanding role fluids dynamics triggering.