基于倒谱的2015年天津港“8·12”爆炸分析

Cepstrum-based Analysis on the “8·12” Explosions of Tianjin Harbor,2015

本文通过对记录到2015年天津港"8·12"爆炸的32个台站的三分量数字地震波形进行倒谱分析,得到了以下结论:(1)2个主要爆炸的发生时间间隔约为32.3s;(2)爆炸-2发生在爆炸-1的西北侧约353°处;(3)依据这些记录的倒谱,无法判定在爆炸-1前是否还存在微小的爆炸。以上结论均与前人研究成果吻合。由于倒谱叠加采用的是全波形,对滤波频带不敏感,因此,在检测发生在同一地点的多次爆炸或其它类似事件(如核爆)上有一定的优势。

By analyzing the cepstra of three component waveforms from 32 stations, which recorded the ＂8·12＂ explosions in Tianjin harbor, we found that：（1） the time difference between the two massive explosions was 32.3 s;（2） the second explosion occurred on northwest of the first explosions, with azimuth about 353°;（3） it was not able to determine whether there existed a small explosion before the explosion-1 or not. All the above findings are consisted well with previous studies. However, in the cepstra-stacking method used in this paper, we applied full waveforms instead of partial waveforms in other studies, and it is not sensitive to filters band. Therefore, our cepstra-stacking method in this study is more efficient than correlation detection method in detecting the explosions with similar events（such as nuclear explosions） happened at the same site.