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。
The frst 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 frst 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.
2017,38(3): 13-17 收稿日期:2016-06-17
DOI:10.3969/j.issn.1003-3246.2017.03.003
基金项目:中国地震台网中心地震台网部日常运维(项目编号:1650301320105)
作者简介:郭铁龙(1988-),男,助理工程师,在职研究生,主要从事数字地震学及地震自动定位工作。E-mail:gtl@seis.ac.cn.
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