上海及邻近地区Pb震相识别

摘要

We selected local earthquake record in the Shanghai area since 2009 and re-picked phase.According to the theoretical travel time curve,the wavelet transform method and the timefrequency analysis can assist in phase identification and confirm to the accuracy of seismic phase.The results show that first arrival Pb phase appeared in the epicenter distance about 100 km in the Shanghai area.While the first arrival phase is the Pn or Pb,the waveform feature has a larger period similar to the sine wave in the initial arrival.%收集2009年以来上海地区近震事件,并重新进行震相拾取.通过走时曲线、时频分析等识别震相的辅助手段,确认震相的可靠性.研究结果表明,上海地区地震的Pb波作为初至震相时,震中距约100 km;初至震相是Pb波时,地震波形类似于正弦波且周期较大.