Abstract:
With example of the 2000 Iceland earthquakes, we use the coseismic and post-seismic response of the near-field groundwater level to constrain the poroelastic parameters and discuss the deformation characteristics due to poroelastic rebound. Firstly, the time series of the water level was calculated according to the pore pressure change obtained by the poroelastic model, and the key parameters of controlling the poroelastic rebound--the Skempton ratio and the hydraulic diffusivity are constrained by observing the coseismic step-like amplitude of the water level and the recovery rate of the postseismic water level. Then, according to the optimal poroelastic parameters, we use numerical simulation methods to calculate the deformation caused by the postseismic poroelastic rebound. The results show that the coseismic response of pore pressure controls the deformation due to poroelastic rebound, and the deformation rate is positively correlated with the hydraulic diffusivity. The deformation caused by poroelastic rebound is mainly vertical and decays rapidly over time. Therefore the coseismic response and postseismic response of the near-field groundwater level can be used to constrain the poroelastic parameters, which provides a basis for obtaining the deformation caused by the postseismic poroelastic rebound.