摘要
依据北京大灰厂台地质构造及30多年的观测资料,建立水文地质力学模型,系统地研究了地下水与地壳形变的相互作用及关系。研究表明,断层活动受构造应力和降雨、地下水产生的流体力共同作用;断层受力方式的改变对地壳形变、地下水位及相互关系产生影响并使观测曲线形态发生变化;地壳形变与地下水位前兆异常是在地震孕育构造应力和降雨、地下水引起的流体力共同作用下产生的非周期性变化。据此提出地震前兆异常的“双力源”观点,震源体膨胀(扩容)产生变形并引起地下流体异常,地下流体异常产生流体力,流体力影响地震孕育、发展和前兆的产生;地震前兆的产生是“双力源”即构造应力和流体力联合作用的结果;构造应力的作用是第一位的,地下流体力则是附加的、调制性的,只有那些能与地震孕育构造应力增强过程产生力学耦合的地下流体力才能调制与诱发出地震前兆异常并促使地震发生。
On the basis of the geologic structure and the observation data for over 30 years at Dahuichang station,Beijing, mutual action and relation between crustal deformation and underground water are studied and its model of hydrogeologic mechanics is built. The results show that fault movement is acted by tectonic stress and subsurface fluid force produced by underground water together. The change of the manner that how the fault is forced can affect on crustal deformation, underground water level and their mutual relation, and make the curve shape of observation data change. The seismic precursory anomaly of crustal deformation and underground water level are non-cyclic changes resulted from the mutual action of the tectonic stress of earthquake preparation and fluid force produced by rain, underground water. A view of seimic precursor of ＂double force source＂ is put forward, its main points are; Earthquake source body dilate to produce crustal deformation and subsurface fluid abnormality which gives rise to the subsurface fluid force influencing earthquake preparation,development and precursor occurrence. Seimic precursor occurrence is the result from the action of ＂double force source＂, namely tectonic stress and the subsurface fluid force. The tectonic stress is primary and the subsurface fluid force is additional or modulating,that only the subsurface fluid force mechanicaly couplling with the tectonic stress of earthquake preparation on its enhancement process may modulate and induce earthquake precursor abnormality, and promote earthquake occurrence.
出处
《大地测量与地球动力学》
CSCD
北大核心
2006年第1期76-83,共8页
Journal of Geodesy and Geodynamics
基金
地震科学联合基金(104009)
关键词
地壳形变
地下水位
流体力
相互作用
“双力源”前兆观点
crustal deformation, underground water level, fluid force, mutual action, a view of ＂double force source＂ seismic precursor
