唐山4.8级地震前易县地震台地应变异常特征

摘要

2012年5月28日河北省唐山发生MS 4.8地震，地震前易县地震台地应变观测数据出现异常，对四分量应变数据、体应变及伸缩仪观测数据，从发震时刻、异常形态、起始和持续时间、异常幅度等进行分析，认为异常在时间和形态上具有一致性，且同一地震台不同观测手段同时监测到异常，可见此异常具有可靠性。%AMS 4.8 earthquake occurred in Tangshan, Hebei Province on May 28, 2012. The earth train observation at Yixian Seismic Station are abnormal, which include the observation of the four component strain, the body strain and the expansion meter. The reliability of these data is verified. The basic situation of abnormal is introduced. The common features of the anomalies are summarized from the abnormal form, the abnormal start and the duration, the abnormal amplitude, the earthquake moment and so on. The analysis shows that the anomaly has the consistency of time and form, and the different observation means of same station at the same time all detect the anomaly, and show that the anomaly has the reliability.