摘要
获得地下含水层的水文参数对于适当评价地下水资源至关重要.除了实验室方法和现场测井实验,目前多利用水位对外部周期性载荷的响应函数进行含水层参数的反演.其中,基于似稳态孔弹性理论的方法有很多,但这些方法通常忽略多孔含水层中可能存在的频率依赖的固流耦合.本文提出基于动态孔弹性理论的水文同震响应模型,推演了频率依赖的含水层孔压和围压的关系,构建动态响应函数.根据云南省腾冲井观测到的近场同震水位响应并基于动态模型反演了井含水层渗透率的长期演化.计算结果显示动态孔弹性模型能很好地解释水位的同震响应并且适当反演含水层参数.近场地震会导致井含水层的短期渗透率大幅度增加并在不久后恢复,这可能与地震触发应力导致的瞬时固体形变、孔隙疏通和颗粒物的重分布有关.
Estimating the hydralic properties of subsurface aquifers is crucial to properly evaluate groundwater resources.Apart from laboratory methods and field logging experiments,the inversion of aquifer parameters is currently mostly performed using the response function of water level to external periodic loadings.Among them,there are many methods based on quasi static poroelasticity,but these approaches have ignored the possible frequency-dependent solid/fluid coupling in the porous aquifer.In this paper,a hydrological coseismic response model based on dynamic poroelastic theory is firstly proposed to derive the frequency-dependent relationship between aquifer pore pressure and stress.By constructing a dynamic response function,the long-term evolution of well aquifer permeability was inferred from the near-field coseismic water level response observed in the Tengchong well in Yunnan Province.The results show that the dynamic poroelastic theory can well explain the coseismic water level response and appropriately invert the aquifer parameters.Near-field seismic can cause a large short-term increase in the permeability of the well aquifer and recover shortly afterwards,which may be related to the transient solid deformation,pore opening,and particle distribution due to the near-field static stress.
作者
高楚林
张煜
张双喜
黄旭东
姚永康
GAO ChuLin;ZHANG Yu;ZHANG ShuangXi;HUANG XuDong(School of Geodesy and Geomatics,Wuhan University,Wuhan 430079,China;Key Laboratory of Geospace Environment and Geodesy,Ministry of Education,Wuhan University,Wuhan 430079,China)
出处
《地球物理学进展》
CSCD
北大核心
2023年第1期12-19,共8页
Progress in Geophysics
基金
国家自然科学基金项目(41774119,41874169,41774056,42074176,U1939204)
中央高校基础研究专项基金项目(2042017kf0228)
武汉大学实验技术专项基金项目(WHU-2019SYJS-12)联合资助。
关键词
井水位
同震响应
动态孔弹性理论
Water level
Coseismic response
Dynamic poroelastic theory
