汶川8.0级地震前兆异常对比研究

THE CONTRAST STUDY OF WENCHUAN M8.0 EARTHQUAKE PRECURSOR ANOMALIES

汶川8.0级地震前兆异常对比研究结果表明,中短临异常台站和台项数与孟连地震相比少近一半。短临阶段汶川地震异常台项增多时间出现在短临阶段早期,孟连、丽江地震出现在晚期。汶川中期异常多数开始于震前2－3年,异常台项数为11,50%以上测值出现巨大变化,孟连中期异常开始于震前1－2年,异常台项数多达20,约30%台项于震前0.5－1年测值出现巨大变化。汶川震中及附近地下水宏观异常始于震前3年并断续延至震前1个月,2%的面积内宏观异常占全省总数的30－50%,绝对数少、相对数多。邢台、唐山、海城及松潘等地震宏观异常出现在震前2－3个月至发震当天,且数量多、强度大,汶川与其他强震前兆共同点是,中短期阶段均有一定数量测值呈现巨大变化的异常出现。

The contrastive research results of Wenchuan M8.0 earthquake precursor anomalies show that the number of items for monitoring earthquake anomalies stations of the imminent short term and medium term is close in part less than that of Menglian earthquake.The number of terms of Wenchuan earthquake anomalies stations increased in the period of early short-term,while it happened in the later period for Menglian and Lijiang earthquake.Most of the medium-term anomalies began 2 to 3 years before Wenchuan earthquake,the number of anomaly station items was eleven,and half of them appear huge change.But to Menglian earthquake,the medium-term anomalies happened 1to 2 years before the earthquake,abnormal station items reached to 20,and 30 percent of them appears huge change 0.5 to1 years before the earthquake.In the epicenter and the nearby area,the macroscopic abnormalities started 3 years and intermittently extended 1 month before the earthquake.Within 2 percent of the area,the macroscopic abnormalities account for 30 percent to 50 percent of the total number of this province,and it started 2 to 3 months to the day of earthquake for Xingtai,Tangshan,Haicheng,Songpan.The common precursors among Wenchuan and other earthquakes are that the appearance anomalies of a certain number of observational show tremendous change.