通过分析西安台近几年各个方向记录到的影区地震，详细阐述了Lg1、Lg2波的确认方法，运用Matlab对数据进行分析，给出了S波与Lg1、Lg2波的走时关系式，提高了影区地震的分析速度和准确度，为单台大震速报和日常分析提供了借鉴经验。

By analyzing the Xi'an station recorded in recent years in all directions shadow zone earthquakes, elaborated Lg1, Lg2 waves confirmation method, using Matlab to analyze data, gives the S wave and Lg1, Lg2 wave travel time relationship improve the shadow zone seismic analysis speed and accuracy for a single earthquake quick report and provide a reference for routine analysis experience.