【摘要】 1999年 11月 2 9日 12时 10分 (北京时间 ) ,中国辽宁省岫岩地区发生一次 5 .4级地震。这次地震前 ,在震区记录到丰富的中小地震活动 ,组成了完整的地震系列。该系列具有小震频度随时间增多 ,震级上升 ,b值较低 ,地震位置集中和地震 P波初动一致 ,将其判断为震前系列 ,并抓住了前震活动从密集突然变为相对平静这一大震即将发生的特征 ,作出了临震预报 ,于 11月 2 8日晚将临震意见通报给辽宁省地震局有关部门。这次地震的预报取得了减灾实效。更多还原

【Abstract】 At 12:10,on November 29,1999,an earthquake of M 5 4 occurred in Xiuyan area,liaoning Province .Before the event,within 20 days,from November 9 to 28,1999,about 240 medium and minor earthquakes were recorded in the area,hence composing a complete earthquake series which had the following features:increasing minor earthquake frequencies with time,the rising of magnitudes,concentration of all event locations and recording comptible seismic P wave onset,and was diagnosed as foreshock series.According to the characters of dense quiet earthquake occurrence,the impending prediction was made,and prediction ideas were reported to the related departments of the Seismological Bureau of Liaoning Province at the evening of November 28.Because of issuing short impending prediction,some suitable countermeasures for earthquake preparedness were taken;good results were achieved in reducing earthquake disasters.更多还原