多种方法综合测定河北昌黎ML4.5地震震源深度

利用CAP、TDMT、sPL深度震相等3种方法测定河北昌黎M_L4.5地震震源深度,利用CAP方法反演得到该地震的震源机制解,拟合得到最佳震源深度为4.5 km;利用TDMT方法反演得到拟合震源深度范围为5~6 km;在震中距20~80 km范围内的台站波形数据中,CHL、BDH两个台站识别到sPL震相,基于震源机制解,计算1~16 km深度范围对应的理论波形图,与观测波形比对后得到震源深度为5 km。结果显示,3种方法的深度研究结果基本一致,结合震源尺度以及昌黎M_L3.9地震CAP、sPL计算结果认为,昌黎M_L4.5地震的震源深度应为4~6 km。

Focal Depth Determination of the Changli ML4.5 Earthquake in Hebei by Multiple Methods

Three methods in this paper were used to determine the focal depth of the Changli M_L4.5 earthquake in Hebei,which were CAP,TDMT and sPL depth seismic phase.First,the focal mechanical solution of Changli earthquake was obtained by using CAP method,and the optimum focal depth was 4.5 km.Then the fitting focal depth range was 5~6 km by using TDMT method.Finally,the waveform data of the stations within the range of 20~80 km from the epicenter were processed,and the sPL seismic phase was identified at two stations,CHL station and BDH station.Based on the focal mechanism solution,the theoretical waveforms corresponding to the 1~16 km depth range were calculated,and by the comparison with the observation waveform,the focal depth was 5 km.The depth research results of the three methods are basically the same,and combined with the focal scale of the Changli M_L4.5 earthquake and calculation results of the Changli M_L3.9 earthquake by CAP and sPL phase,it shows that the focal depth of the Changli M_L4.5 earthquake should be 4~6 km.