STA/LTA—AIC算法对地震P波震相拾取稳定性影响

摘要

The first P arrivals of the selected earthquakes are picked automatically from the regional waveform data by using both STA/LTA and STA/LTA—AIC algorithms. In this paper, the effect of the P-phase picks of the local and distant events is analyzed. It is concluded that the arrival times of the first P phases picked with the STA/LTA method are of high precision, and differ slightly from the ones with the STA/LTA—AIC; When the epicenters become more distant, the P arrivals picked with the STA/LTA are delayed from the best positions, which will be corrected effectively by the STA/LTA—AIC algorithm, thus the differences between the corrected positions and the manual results are negligible.%选取区域地震台网记录的地震波形数据,使用STA/LTA算法与STA/LTA—AIC算法,进行地震P波震相初至到时自动拾取,对地方震及震中距较大的震相进行P波震相拾取效果分析,发现:STA/LTA算法对于地方震P波震相识别精度较高,与STA/LTA—AIC算法拾取的P波震相初至到时相差不大;震中距变大后,STA/LTA算法对P波拾取位置相对于最佳位置向后延迟,STA/LTA—AIC算法有效矫正了STA/LTA算法拾取位置的延迟问题,与人工拾取位置差别可忽略不计.