青海门源Ms6.4地震震源机制解与震源深度研究

摘要

Based on waveform data recorded by 19 broadband digital stations of Gansu,Qinghai and Ningxia regional seismic network,we use the CAP method to calculate the focal mechanism solution and the optimal focal depth of Menyuan Ms6.4 earthquake in January 21,2016.The results show that the double-couple solution is:nodal Ⅰ:strike 143°,dip angle 40°,slip angle 71°;nodal Ⅱ:strike 347.2°,dip angle 52.6°,slip angle 105.3°.The moment magnitude is Mw5.9 and the optimal depth is 7.7km,which is consistent with the results of others (such as CENC,IGP-CEA and Harvard).Using the arrival time difference between sPn phase extracted by sliding window correlation method,we obtain the focal depth of 8.5 km,which is coincident with the result of CAP inversion,and we validate the feasibility of the method.%选取甘肃、青海和宁夏区域测震台网19个宽频带数字台站的地震波形,采用CAP震源机制解方法,研究2016-01-21青海省门源县Ms6.4地震,得到其震源机制解和最佳震源深度.反演结果显示,最佳双力偶解为,节面I:走向143°,倾角40°,滑动角71°,节面Ⅱ:走向347.2°,倾角52.6°,滑动角105.3°,地震矩震级为Mw5.9,最优深度解为7.7 km,与其他结果(CENC、IGP-CEA、Harvard)基本一致.利用滑动时窗相关法提取Pn、sPn震相,再利用其到时差测定震源深度为8.5 km,与CAP结果基本一致,验证了该方法的可行性.