岫岩5.4级地震前后地震活动的演化及短临异常标志研究

STUDY ON SEISMICITY EVOLUTION AND SHORT-TERM AND IMMINENT ANOMALY INDEXES BEFORE AND AFTER XIUYAN M_S 5.4 EARTHQUAKE

应用"八五"和"九五"地震预报攻关成果中的40多种地震活动性参数分析方法,对1999年11月29日岫岩5 4级地震前后地震活动的演化及其特征作了详细研究。结果发现其中一些参数的演化过程,在岫岩5 4级地震前存在不同程度的异常显示,而在其后2000年1月12日5 1级余震临震前除了少数个别参数有异常显示外多数没有明显的异常反应。根据5 4级地震前各参数值的演化特征及其在异常阶段的变化情况与背景值的差异程度,提取了一些参数的中、短、临异常判定指标或标志,作为本地区中强震短、临预报及方法研究参考。

In this paper,making use of analytical methods over 40 seismicity parameters in the scientific research achievements during 'The 8th FiveYear Plan'and 'The 9th FiveYear Plan',the evolution and characteristic of seismicity before and after Ms 54 earthquake occurred in Xiuyan on November 29,1999 are studied in detail.In the result,we found that in the evolution processes of some parameters of them,there are anomaly showing in varying degrees before the Ms 54 earthquake and that prior to the Ms 51 aftershock on January 12,2000,there are not obvious anomaly response in the evolution processes of most parameters with the exception of very few parameters.According to the evolution characteristics of each parameter value before the Ms 54 earthquake and to the different degrees between their changing amplitudes during anomaly period and corresponding background values,the judging indexes(or signs)in midterm,shortterm and imminent earthquake anomalies of some Parameters are extracted so that they are referenced as shortterm and imminent prediction research of moderately strong earthquake in this region.