台湾海峡南部一次5．0级地震的sPn震相分析

sPn seismic phase analysis for a M_L5.0 earthquake in southern Taiwan Strait

运用Pn震相对齐测定sPn震相的方法分析了发生在台湾海峡南部的一次5．0级地震的 sPn震相,初步了解sPn震相的一些特征,并在不同地壳模型下用sPn-Pn的走时差计算了该地震的震源深度。结果表明:在该地震中,sPn震相特征明显;用Pn震相对齐测定sPn震相的方法可以快速、可靠地测定出sPn震相;用sPn-Pn的走时差计算震源深度时,不同模型计算出的结果相差不大。

In the paper, using the method of Pn seismic phase coming into line to determine sPn phase, we analyzed the sPn phase of a M 5.0 earthquake occurred in southern Taiwan strait and understood some characteristics of sPn phases. We also calculated the hypocenter depth of the earthquake in different crust models using sPn phases. The results showed that in the seismic waveform, the characteristics of sPn phases are clear. It also showed that using the method, the sPn phases could be determined quickly and reliable. Using the travel-time difference of sPn- Pn to calculate the source depth with different models, the differences among results are not significant.