两次中等地震的预测及其震前异常分析
THE PREDICTION ABOUT TWO MEDIUM SIZE EARTHQUAKES AND THE ANALYSIS FOR IT'S PRECURSOR ANOMALIES
-
摘要: 1993 年11 月18 日及1998 年4 月4 日在天津市宝坻县和唐山强震区的钱营分别发生 ML4.4 级和 ML5.0 地震各一次,在这两次中等地震前,分别显示出中期地震活动空间分布及短临性水化学观测异常,其表现形式明显不同。本文在客观介绍上述异常的基础上,结合它们所属的地震类型、发震的构造背景以及相关地震的分析比较,对它们震前的异常表现形式不同的原因进行分析和探讨,并初步得出中等地震前产生不同异常显示的基础条件和相关因素的认识。Abstract: On Nov. 18th,1993 and Apr.17th,1998,the earthquakes with Magnitudes 4.4 and 5.0 occurred respectively in Baodi County of Tianjin region and Qianying of Tangshan region.Before the first medium size event,the spacial anomaly of seismictity distribution was showed,and before the Socand,the short-impending anomalous change of hydrogeochemistry was showed.In this paper,based on the introduction about above the anomalies objectively,the analysis was made for the cause of the defferent patterns of the anomaly combining with the seismic types and the tectonic background of earthquake occurrence and comparing with the correlation earthquakes.The preliminary knowlege has been obtained about the background conditions and the correlation factors causing the different anomalies.