刘战天,刁法启,付誉超,熊熊. 2023. 基于地下水位观测的震后孔隙回弹研究:以2000年冰岛地震为例. 地震学报,45(6):1−12. doi: 10.11939/jass.20220050
引用本文: 刘战天,刁法启,付誉超,熊熊. 2023. 基于地下水位观测的震后孔隙回弹研究:以2000年冰岛地震为例. 地震学报,45(6):1−12. doi: 10.11939/jass.20220050
Liu Z T,Diao F Q,Fu Y C,Xiong X. 2023. Post-seismic poroelastic rebound using groundwater level observations:Taking the 2000 Iceland earthquakes as an example. Acta Seismologica Sinica45(6):1−12. doi: 10.11939/jass.20220050
Citation: Liu Z T,Diao F Q,Fu Y C,Xiong X. 2023. Post-seismic poroelastic rebound using groundwater level observations:Taking the 2000 Iceland earthquakes as an example. Acta Seismologica Sinica45(6):1−12. doi: 10.11939/jass.20220050

基于地下水位观测的震后孔隙回弹研究:以2000年冰岛地震为例

Post-seismic poroelastic rebound using groundwater level observations:Taking the 2000 Iceland earthquakes as an example

  • 摘要: 以2000年两个MW 6.5冰岛地震为例,利用近场地下水位的同震和震后响应约束孔隙模型参数,研究了孔隙回弹效应的变形大小和时间特征。首先利用数值模拟方法计算地震造成的孔隙压力变化和测井水位响应的时间序列,并以测井水位的同震阶跃幅值和震后水位恢复速率分别约束Skempton系数和扩散系数;然后根据最优的孔隙参数模拟计算震后孔隙回弹效应引起的地壳变形。结果显示:孔隙压力的同震响应控制着孔隙回弹引起的地壳变形,其变形速率与流体扩散系数呈正相关关系;孔隙回弹造成的变形以垂直向为主,且随时间快速衰减。因此,利用近场地下水位的同震响应和震后响应可以约束孔隙介质参数,为获取震后孔隙回弹机制造成的变形提供依据。

     

    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.

     

/

返回文章
返回