摘要
地下流体是地壳中非常活跃的组成部分,它具有流动性和不可压缩性.岩石力学实验结果表明,地震孕育和发生时,会在孕震区局部产生应力集中和大量微裂隙,随着应力的重新分布,发生明显的裂隙开闭等可观测的变化.流体可以把地下深处与地震孕育有关的岩体物理状态变化等信息带到地表,如承压水井的井水位可以用来观测含水层中的体应变,同位素浓度等物理量可以反映流体渗流途径中岩体连通性的改变,在一定条件下可以在地表产生可观测的地震前兆异常现象.关于地下流体发展了一些重要的地震预测方法,本文主要总结了前人关于这些方法的理论和实践,讨论了如何建立地下水短期及临震预兆与地震三要素之间的联系,分析了地下流体反映地震孕育过程需要满足的条件,并对与地下流体有关的地震预测方法进行了讨论.
Subsurface fluid is one of the most active material in Earth＇s crust.It can flow and it is incompressible.Rock fracture experiments show that,there is localized stress concentration in earthquake generating area,which produces micro fractures.With stress redistribution,obvious phenomena such as the opening and closing of cracks can be observed.Fluids can take information of rocks ＇ mechanics characteristic related to the generation of earthquakes to the surface.For instance,the variation of stress field will cause the change of groundwater level in confined water well.Isotope concentration can reflect the change of the connectivity of rock along the seepage path.With these mechanisms,observable seismic precursors will be produced in the surface under certain condition.Some important earthquake prediction methods related to subsurface have been developed.In this paper,theories and practices about these methods are summarized.Then we discuss how to establish the link between short term and impending precursors of subsurface fluid and the ＇three elements＇ of earthquakes,as well as what the condition is for these precursors to reflect the process of earthquake generation.Finally,we make some suggestions to improve earthquake prediction method related to subsurface fluid.
出处
《地球物理学进展》
CSCD
北大核心
2017年第4期1539-1547,共9页
Progress in Geophysics
基金
国家自然科学基金项目(40872133
40821062
41274094)资助
关键词
地下流体
井水位
地震预测
subsurface fluid
water level
earthquake prediction
