华南地震

对海南三亚市2019年8月20日M4.2和M3.2两次地震的波形特征和震源参数进行对比分析。利用sPL震相与 P震相到时差,计算三亚两个地震的震源深度在11 km左右。采用CAP方法进行地震波反演计算,最佳震源深度为分别为9.5 km、10.9 km,两次地震的震源机制基本一致,均是正断层兼走滑型地震,说明两次地震的震中构造环境及应力场作用方式相同。

This paper compares the waveform characteristics and source parameters of the M4.2 and M3.2 earthquakes in Sanya,Hainan on August 20th,2019. The focal depth of the two earthquakes in Sanya is calculated to be about 11 km by using the time difference between the sPL phase and the P phase. The CAP method was used for seismic wave inversion calculation. The optimal focal depths were 9.5 km and 10.9 km respectively. The focal mechanisms of the two earthquakes were basically the same,both of which are normal faults and strike-slip earthquakes,indicating that the epicentral structure environment and stress field of the two earthquakes are the same.

引言
1 波形特征
2 震源参数计算分析
3 总结与存在的问题

图1 三亚4.2 、3.2级地震震中图<br/>Fig.1 The epicenter map of the Sanya M4.2 and M3.2 earthquakes

图1 三亚4.2 、3.2级地震震中图
Fig.1 The epicenter map of the Sanya M4.2 and M3.2 earthquakes

图2 SmS震相传播路径<br/>Fig.2 SmS phase propagation path

图2 SmS震相传播路径
Fig.2 SmS phase propagation path

图3 三亚4.2级地震SmS震相<br/>Fig.3 SmS phase of Sanya M4.2 earthquake

图3 三亚4.2级地震SmS震相
Fig.3 SmS phase of Sanya M4.2 earthquake

图4 三亚3.2级地震SmS震相<br/>Fig.4 SmS phase of Sanya M3.2 earthquake

图4 三亚3.2级地震SmS震相
Fig.4 SmS phase of Sanya M3.2 earthquake

图5 均匀半空间下sPL和直达P波的传播路径<br/>Fig.5 Propagation paths of sPL and direct P waves in uniform half-space

图5 均匀半空间下sPL和直达P波的传播路径
Fig.5 Propagation paths of sPL and direct P waves in uniform half-space

图6 三亚4.2级地震记录的sPL震相<br/>Fig.6 The sPL phase of the Sanya M4.2 earthquake

图6 三亚4.2级地震记录的sPL震相
Fig.6 The sPL phase of the Sanya M4.2 earthquake

图7 三亚3.2级地震记录的sPL震相<br/>Fig.7 The sPL phase of Sanya M3.2 earthquake2 震源新参数

图7 三亚3.2级地震记录的sPL震相
Fig.7 The sPL phase of Sanya M3.2 earthquake2 震源新参数

图8 三亚4.2级(a)、3.2级(b)地震震源机制解<br/>Fig.8 Focal mechanism solutions of Sanya M4.2,M3.2 earthquakes

图8 三亚4.2级(a)、3.2级(b)地震震源机制解
Fig.8 Focal mechanism solutions of Sanya M4.2,M3.2 earthquakes

图9 三亚4.2级(a)、3.2级(b)地震震源深度拟合误差<br/>Fig.9 Fitting error of focal depth of Sanya M4.2,M3.2 earthquakes

图9 三亚4.2级(a)、3.2级(b)地震震源深度拟合误差
Fig.9 Fitting error of focal depth of Sanya M4.2,M3.2 earthquakes

图10 三亚4.2级、3.2级地震波形拟合图<br/>Fig.10 Waveform fitting diagram of Sanya M4.2,M3.2 earthquakes

图10 三亚4.2级、3.2级地震波形拟合图
Fig.10 Waveform fitting diagram of Sanya M4.2,M3.2 earthquakes

图11 三亚4.2级(a)、3.2级(b)地震震源谱图<br/>Fig.11 Source spectrum of the Sanya M4.2,M3.2 earthquakes

图11 三亚4.2级(a)、3.2级(b)地震震源谱图
Fig.11 Source spectrum of the Sanya M4.2,M3.2 earthquakes

表1 三亚4.2级、3.2级地震震源新参数<br/>Table 1 New focal parameters of the Sanya M4.2,M3.2 earthquakes

表1 三亚4.2级、3.2级地震震源新参数
Table 1 New focal parameters of the Sanya M4.2,M3.2 earthquakes

图12 参与计算三亚4.2级地震震源新参数台站分布（a）和方位角(b)<br/>Fig.12 Distribution(a) and azimuth(b) of stations participating in calculation of new source parameters of Sanya M4.2 earthquake

图12 参与计算三亚4.2级地震震源新参数台站分布（a）和方位角(b)
Fig.12 Distribution(a) and azimuth(b) of stations participating in calculation of new source parameters of Sanya M4.2 earthquake

图13 参与计算三亚3.2级地震震源新参数台站分布（a）和方位角(b)<br/>Fig.13 Distribution(a) and azimuth(b) of stations participating in calculation of new source parameters of Sanya M3.2 earthquake

图13 参与计算三亚3.2级地震震源新参数台站分布（a）和方位角(b)
Fig.13 Distribution(a) and azimuth(b) of stations participating in calculation of new source parameters of Sanya M3.2 earthquake

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备注

引言

1 波形特征

2 震源参数计算分析

3 总结与存在的问题

期刊信息