sPn震相特征及在震源深度测定中的应用  

Characteristics of sPn phase and its application in focal depth determination

作　　者：孙茁[1,2] 吴建平[1] 蔡妍[1] 

机构地区：[1]中国地震局地球物理研究所,中国北京100081 [2]中国地震局地震研究所地震大地测量重点实验室,中国武汉430071

出　　处：《地震地磁观测与研究》2014年第3期89-95,共7页Seismological and Geomagnetic Observation and Research

基　　金：地震行业科研专项(201308013);国家科技支撑计划(2012BAK19B01)资助

摘　　要：通过理论地震图模拟,研究sPn震相特征,分析其影响因素。研究表明:sPn与Pn震相的初动极性关系在不同台站方位角呈现不同特点,基于sPn震相的深度定位方法更适合于中强地震。以2012年9月7日12时16分彝良M_S 5.6地震为例,利用南北地震带南段密集流动地震台阵的观测数据,采用波形互相关方法拾取Pn波走时,应用滑动时窗相关法识别sPn震相,通过sPn与Pn震相走时差,测定震源深度为9.6 km。With modeling theoretical seismograms,we studied the characteristics of sPn phase and analyzed the factors that may affect the phase.The result showed that the polarity of sPn with different azimuth angle may be different,and the depth location method based on the sPn phase is more suitable for M 4.0-6.0 earthquakes.Taking the Yiliang MS 5.6 ecent on September 7,2012 as an example,we obtained its focal depth is 9.6 km using the seismic waveforms recorded by the seismic array deployed in the southern section of the North-South seismic belt.The focal depth is determined from the arrival-time differences between sPn and Pn phase.The Pn waves are picked by the waveform cross-correlation method,and the sPn phases are identified by using the sliding-window correlation method.

关 键 词：震源深度 深度震相 SPN震相 波形互相关 滑动时窗相关法 彝良地震 

分 类 号：P315[天文地球—地震学]