地震研究

利用青海省遥测地震台网的观测记录,对比分析震相特征,提取出了两次地震记录的sPn震相,并分别推导出单、双层地壳模型下的震源深度公式,计算了两次地震事件的震源深度。为验证计算结果的可靠性,利用滑动窗互相关技术进行对比,两者计算出的震源深度相差1.0 km。但分析相关系数图后,认为由于地震震级较小,滑动窗法在识别sPn震相时存在误差,误差修正后得出的结果与人工识别计算的结果一致。

Based on observation data recorded by Qinghai Remote Digital Seismic Network, we exacted the sPn phases of Golmud M4.0 and M3.6 earthquakes by phase characteristic comparison. Then we derived the mathematical formula of focal depth in the case of single-layer and two-layer model respectively, and calculated the focal depth of these two earthquakes. In order to verify the reliability of the calculation results, we compared the focal depth determined by the cross-correlation technique of sliding window with the artificial recognition, and found that the difference of the focal depth by two methods is 1.0 km. After observing the correlation coefficient, there exits an error while we identified the sPn phase by the sliding window method because of the magnitude of the earthquake are small, however, the arrival times of the obtained phases are in agreement with that of the artificial recognition after error correction.

引言
1 sPn波的射线路径和走时方程
2 sPn震相识别与震源深度计算
3 与波形互相关结果对比
4 结论与讨论

图1 单层地壳模型中sPn与Pn的射线路径<br/>Fig.1 Radial paths of sPn and Pn in the single layer crustal model

图1 单层地壳模型中sPn与Pn的射线路径
Fig.1 Radial paths of sPn and Pn in the single layer crustal model

图2 双层地壳模型震源在上地壳内sPn与Pn的射线路径<br/>Fig.2 Radial paths of sPn and Pn when the focus located in the upper crust in the double crustal model

图2 双层地壳模型震源在上地壳内sPn与Pn的射线路径
Fig.2 Radial paths of sPn and Pn when the focus located in the upper crust in the double crustal model

图3 双层地壳模型中震源在下地壳内sPn与Pn的射线路径<br/>Fig.3 Radial paths of sPn and Pn when the focus located in the lower crust in the double crustal model

图3 双层地壳模型中震源在下地壳内sPn与Pn的射线路径
Fig.3 Radial paths of sPn and Pn when the focus located in the lower crust in the double crustal model

表1 青海格尔木M4.0地震sPn与Pn震相的特征参数对比<br/>Tab.1 Comparison of the characteristic parameter of sPn and Pn phases of Qinghai Golumd M4.0 earthquake

表1 青海格尔木M4.0地震sPn与Pn震相的特征参数对比
Tab.1 Comparison of the characteristic parameter of sPn and Pn phases of Qinghai Golumd M4.0 earthquake

表2 青海格尔木M3.6地震sPn与Pn震相的特征参数对比

图4 按Pn到时对齐的记录波形<br/>Fig.4 Recording waveforms after Pn phase alignment

图4 按Pn到时对齐的记录波形
Fig.4 Recording waveforms after Pn phase alignment

图5 利用滑动窗相关法得到的相关系数图<br/>Fig.5 The correlation coefficients by using sliding window cross-correlation method

图5 利用滑动窗相关法得到的相关系数图
Fig.5 The correlation coefficients by using sliding window cross-correlation method

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备注

引言

1 sPn波的射线路径和走时方程

2 sPn震相识别与震源深度计算

3 与波形互相关结果对比

4 结论与讨论

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