地下水诱发的浅层前兆异常及其机理与有关的地震预报问题(1)

The mechanism of shallow layers anomaly caused by groundwater and its related question in earthquake prediction

依照“源、场、外”相结合的地震科学研究思路 ,提出地下水诱发浅层前兆异常机理。认为降水等因素造成的地下水动态变化 ,可产生一种作用于地壳岩石的附加流体力 ;地震前 ,通过多种流体力作用 ,引起已经积累较高应力的地壳应力——应变场调整变化 ,并使岩石强度改变 ,从而促进与诱发浅层地壳的构造变动 ;其结果是派生或伴生出地形变、地应力、水化学及地电阻率等多种浅层前兆异常。在降水、地下水的多种周期变化成分中 ,只有那些能与地壳应力 -应变过程产生力学耦合的周期变化 ,才能调制与诱发出异常 ,这一部分变化可做为广义的地震前兆。孔隙压力、动水压力以及化学腐蚀等原理 ,是该异常机理的理论基础。列举出六方面的事实做为该机理直接的或间接的证据。

Based on the consideration of combining 'source,field,outside',the anomaly mechanism caused by groundwater in shallow layer is put forward.The dynamic variation of ground water caused by rain may produce an additional force to the rock.Before an earthquake,since the action of many fluid forces,the crustal stress field begins to adjust,and change the intensity of rock so that it causes tectonic movement of shallow crust.The result is many precursory anomalies in shallow layer associate,such as crustal deformation,crustal stress,hydrochemistry and earth resistivity.Among many periodical variation of rain and groundwater,only those that can be coupled with stress strain course can cause anomaly,which can be defined as generalized precursor.The principles of pore pressure, fluid pressure and chemical erosion are the theoretic foundation of this anomaly mechanism.As direct and indirect evidence of the mechanism 6 facts are presented.