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摘要: 主要分析全球地震台网牡丹江和白家疃地震台记录的2006年10月9日、2009年5月25日和2013年2月12日的3次爆炸事件。主要通过3次事件P震相振幅比和功率谱比值估计了3次事件的能量比,采用互相关方法计算了3次事件的相关系数,对比震相波形探讨3次事件发生的相对位置。2013年的爆炸事件与2009年的爆炸事件相比,三分向最大单振幅比值和功率谱比值平均分别为2.2和2.6;与2006年的爆炸事件相比,三分向P震相最大单振幅比值和功率谱比值平均分别为11.1和13.9。该结果暗示了2013年爆炸事件释放的能量高于2009年爆炸事件的2倍,高于2006年爆炸事件的10倍。在2~4 Hz频段内,2013年爆炸事件与2006年爆炸事件、2009年爆炸事件三分向波形的最大相关系数平均分别为0.90和0.99。相关性分析结果表示,3次爆炸事件在能量的主要集中频段高度相关,这表明3次爆炸事件发生的位置相距很近。相对位置分析表明,2013年爆炸事件发生的位置在2009年爆炸事件发生位置的东偏南方向。Abstract: The three explosion events recorded by Mudanjiang and Baijitong sesimic stations on October 9, 2006, May 25, 2009 and Feburary 12, 2013 were analyzed, respectively.Both the stations belong to Global Sesimic Network.The energy ratios of the three events were estimated by comparing the maximum P-phase amplitudes and the power spectrum densities, and the correlation coefficients of the three explosion events were determined.The phases were compared to determine the relative location of these explosion events.Comparison between the 2013 event and the 2009 event displays that the mean ratios of the maximum amplitudes and the power spectrum densities are about 2.3 and 2.7, respectively.The results for the 2013 event and the 2006 event displays that the mean ratio of the maximum amplitudes is about 10.1 and the mean ratio of the power spectrum densities is about 13.5.It indicates that the energy released by the 2013 event is about 11.8 times as much as that released by the 2006 event and 2.5 times as much as that released by the 2009 event.The maximum cross correlations were 0.90 and 0.99 for the 2013, 2006 events and the 2013, 2009 events in 2-4 Hz, respectively.These results mean that the 2013 event is highly correlated to the 2006 and 2009 events in the frequency band which the main energy concentrated, and this shows that the relative distances of the three events are not long.The analysis on the relative locations of these three events can explain that the 2013 event lies to the southeast of the 2009 events.
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Key words:
- mechanics of explosion /
- relative location /
- energy ratio /
- explosion event /
- correlation
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表 1 牡丹江地震台Z向记录的3次爆炸事件的振幅比
Table 1. Amplitude ratios between three explosion events recorded by Mudanjiang seismic station in vertical direction (Z)
A13/A09 A13/A06 Pg 瑞利波 Pg 瑞利波 2.2 2.4 11.1 9.1 表 2 E13与E06、E09 Pg和瑞利波的功率谱比
Table 2. Power spectrum ratios of E13 to E06 and E09
P13/P09 P13/P06 Pg 瑞利波 Pg 瑞利波 2.6 2.7 13.9 13.0 -
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