基于甘肃地震台网和青海地震台网对岷县-漳县MS6.6地震和门源MS6.4地震的波形记录，采用FFT方法分别计算这两次地震三分向的峰值速度，讨论分量之间峰值速度比的分布特征，进而研究其震源性质。结果表明，岷县-漳县地震具有逆冲兼左旋位错性质，南北向能量明显大于东西向；门源地震以逆冲为主，略具左旋走滑特征，两个水平分量的能量相当。结合这两次地震的余震序列分布特征及其他学者的研究结果推测，岷县-漳县地震的发震断层应该是位于临潭-宕昌断裂西北侧且与其平行的一条次级断裂；门源地震的发震断层应该是冷龙岭断裂西北侧的次级断裂，但受到冷龙岭断裂活动控制。"/>
Distribution Characteristics of Peak Velocity Ratio and Its Aftershocks on Two Strong Earthquakes" />
Based on the waveform records of the Minxian-Zhangxian MS6.6 and Menyuan MS6.4 earthquakes recorded by Gansu and Qinghai seismic network, we calculate the peak velocities in three components of the two earthquakesby the FFT method. We discuss the geographical distribution characteristics of the peak velocity ratio between components. The results show that the Minxian-Zhangxian earthquake is characterized by thrusting and sinistral dislocation, and the energy of the south-north component is obviously greater than that of the east-west component when we compare the two horizontal directions. The Menyuan earthquake is a thrusting earthquake with slight left-lateral strike-slip, and the energy of two horizontal components is equal. Based on the distribution characteristics of aftershocks of these two earthquakes and the research results of other scholars, we infer that the seismogenic fault of Minxian-Zhangxian earthquake should be a secondary fault which is parallel to Lintan-Tangchang fault, and the seismogenic fault of Menyuan earthquake should be a secondary fault on the northwest side of Lenglongling fault, but controlled by the activity of Lenglongling fault."/>
两次强震峰值速度比及其余震分布特征
Abstract：Based on the waveform records of the Minxian-Zhangxian MS6.6 and Menyuan MS6.4 earthquakes recorded by Gansu and Qinghai seismic network, we calculate the peak velocities in three components of the two earthquakesby the FFT method. We discuss the geographical distribution characteristics of the peak velocity ratio between components. The results show that the Minxian-Zhangxian earthquake is characterized by thrusting and sinistral dislocation, and the energy of the south-north component is obviously greater than that of the east-west component when we compare the two horizontal directions. The Menyuan earthquake is a thrusting earthquake with slight left-lateral strike-slip, and the energy of two horizontal components is equal. Based on the distribution characteristics of aftershocks of these two earthquakes and the research results of other scholars, we infer that the seismogenic fault of Minxian-Zhangxian earthquake should be a secondary fault which is parallel to Lintan-Tangchang fault, and the seismogenic fault of Menyuan earthquake should be a secondary fault on the northwest side of Lenglongling fault, but controlled by the activity of Lenglongling fault.
