摘要
通过分析唐山、大同、海城等强震的地电前兆,提出判断地震前兆的主要标准:直接或间接反映应变积累的信息可定为地震前兆。论证唐山地震前2—3年区域电阻率下降是该区震前应变积累的反映,即唐山震前地电区域下降是地震的中期前兆。地电中期前兆具有震中区幅度较大,外围较小,前兆从震中向外围传播等规律。地电前兆中期向短临过渡的判据有:加速、回返、各向异性及触发等。
Based on analyzing the geoeletric precursors occurred during Tangshan, Datong, Haicheng earthquake, authors presented the principal criteria for recognizing the earthquake precursors in this paper, i.e the information, which directly or indirectly reflects the strain accumulation, can be regarded as the earthquake prcursors. The authors also demonstrated that the decline of regional electrical resistivity occurred 2-3 years before Tangshan earthquake should be the reflection of strain accumulation before earthquake occurrence in this area, or say, such a decline is a middle-term earthquake precursor. The middle-term precursor of geoelectric observation shows the following features: the larger amplitude occurred in the epicentral area, smaller in the periphery, as well as the precursor was spread from the epicenter to the periphery. The criteria for the transition from the middle-term to the short-term and impending anomalies are: accelaration, returning, anisotropy and triggering of the precursory changes.
出处
《地震》
CSCD
北大核心
1995年第4期308-314,共7页
Earthquake
基金
国家自然基金会资助课题(49374197)
国家地震局"八五"攻关项目(85-04-02-02)。
关键词
地电阻率
短临异常
地震前兆
综合判据
Ground resistivity, Short-impending anomaly, Accelaration, returning
