摘要
使用伪魏格纳-维勒时频分析方法 ,对中国大陆东经108°以东,2007年至2015年M4.5以上地震进行分析,发现:(1)在震前3个月内,伪魏格纳-维勒时频分析高值异常的异常频次增多,异常密度加大,异常频次密度相比于全年平均水平上升2~3倍左右。(2)震中距200km以内,异常较为明显,具有异常幅度随震中距增大而幅度减小的特征,且震前1个月内有出现全年极值的可能。因此,当短时间内(1~3个月)出现异常频次明显增多(排除外空场影响),异常频次密度达到全年平均水平的2~3倍时,应注意该异常区200km范围内发生M4.5左右地震的可能。
Using time-frequency analysis method based on the pseudo-Wigner-Ville distribution（SPWVD）, we analyzed earthquakes greater than Ms4. 5 between 2007 and 2015 and east of 108°E. We found that （1） 3 months before the earthquakes, the SPWVD timefrequency analysis of the abnormal high value anomaly frequency increased, and anomaly density also increased. Abnormal frequency density rise around 2-3 times compared to the year average. （2） The epicenter distance is within 200 kin, and the anomaly is relatively obvious, abnormal amplitude with the epicenter distance increased, and the characteristics of amplitude decreases, and within a month before the earthquake has the potential of full- year extremum. Therefore, when abnormal frequency increased markedly in a short period of time （1-3 months） （excluding outer influence）, abnormal frequency density reached 2 to 3 times the average for the whole year, we should pay more attention to possible Ms 4.5 earthquake in the abnormal area of 200 km range.
出处
《地震》
CSCD
北大核心
2018年第1期61-73,共13页
Earthquake
基金
天津市"十二五"地震监测技术系统完善与建设项目
2016年度震情跟踪定向工作任务(重点)(2016030506)资助
