地震研究

利用发生在赣南地区的183次M_L≥1.0地震资料,采用尾波归一化方法对寻乌、安远和龙南3个台站的P波、S波品质因子Q_P和Q_S值进行了计算,分析了该地区地壳介质的衰减特征。研究结果表明,寻乌(流逝时间35 s)和龙南台(流逝时间40 s)Q_P值较可靠且值相近,拟合平均值为Q_P(f)=(20.76+1.67)*f^(1.03±0.04),寻乌台和安远台(流逝时间均为21 s)拟合平均值为Q_S(f)=(18.86+1.46)*f^(0.84±0.04)。Q值总体呈现低Q₀和高η值的特点,这是构造运动活跃地区的特征体现,也和该地区中强地震比较活跃的特征相符。

Using 183 M_L≥1.0 earthquakes occurred in south of Jiangxi province, we calculate the quality factors for P(Q_p)and S waves(Q_S)of the Xunwu,Anyuan and Longnan stations by the extended coda-normalization method, and investigated the seismic attenuation properties of the crust medium in the study area. The results show that the Q_p value of Xunwu(lapse time is 35s)and Longnan stations(lapse time is 40 s)is reliable and close, the average value of the fitting result is Q_P(f)=(20.76±1.67)*f ^(1.03±0.04),and the average value of Q_S of Xunwu and Anyuan stations(lapse time is 21s)is Q_S(f)=(18.86±1.46)*f ^(0.84±0.04). The characteristic of Q value indicates low Q₀ and high η, which means that the tectonic movement is active, and is consistent with the characteristic of the moderately strong earthquakes which are active in the study area.

引言
1 方法原理
2 资料选取与处理
3 计算结果与分析
4 结论与讨论

图1 赣南地区台站和地震活动分布图<br/>Fig.1 Distribution of seismic stations and seismicity in south of Jiangxi Province

图1 赣南地区台站和地震活动分布图
Fig.1 Distribution of seismic stations and seismicity in south of Jiangxi Province

表1 3个台站各频带的P波Q值结果(ML≥1.0)<br/>Tab.1 Q value of P wave at different frequencies of three seismic satations(ML≥1.0)

表1 3个台站各频带的P波Q值结果(ML≥1.0)
Tab.1 Q value of P wave at different frequencies of three seismic satations(ML≥1.0)

表2 3个台站各频带的S波Q值结果(ML≥1.0)<br/>Tab.2 Q value of S wave at different frequencies of three seismic stations(ML≥1.0)

表2 3个台站各频带的S波Q值结果(ML≥1.0)
Tab.2 Q value of S wave at different frequencies of three seismic stations(ML≥1.0)

图2 寻乌台经尾波归一化后S波振幅随震源距的衰减<br/>Fig.2 The peak amplitude of S wave attenuated with epicenter distance derived by using the extended coda-normalization method at Xunwu Station

图2 寻乌台经尾波归一化后S波振幅随震源距的衰减
Fig.2 The peak amplitude of S wave attenuated with epicenter distance derived by using the extended coda-normalization method at Xunwu Station

图3 寻乌台S波尾波归一化Q值频率曲线图<br/>Fig.3 Q-value frequency curve for S wave after coda-normalization at Xunwu Station

图3 寻乌台S波尾波归一化Q值频率曲线图
Fig.3 Q-value frequency curve for S wave after coda-normalization at Xunwu Station

图4 寻乌台S波尾波归一化Q0值随流逝时间的变化<br/>Fig.4 Q0 value varied with lapse time for S wave derived by using the extended coda-normalization method at Xunwu Station

图4 寻乌台S波尾波归一化Q0值随流逝时间的变化
Fig.4 Q0 value varied with lapse time for S wave derived by using the extended coda-normalization method at Xunwu Station

表3 寻乌台不同流逝时间对应的S波尾波归一化Q0值<br/>Tab.3 Q0 value for S wave in different lapse time derived by using the extended coda-normalization method at Xunwu Station

表3 寻乌台不同流逝时间对应的S波尾波归一化Q0值
Tab.3 Q0 value for S wave in different lapse time derived by using the extended coda-normalization method at Xunwu Station

图5 尾波归一化Q值频率曲线图<br/>(a)寻乌龙南区域(P波);(b)寻乌安远区域(S波)<br/>Fig.5 Q-value frequency graph derived by using the extended coda-normalization method

图5 尾波归一化Q值频率曲线图
(a)寻乌龙南区域(P波);(b)寻乌安远区域(S波)
Fig.5 Q-value frequency graph derived by using the extended coda-normalization method

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备注

引言

1 方法原理

2 资料选取与处理

3 计算结果与分析

4 结论与讨论

期刊信息