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本文对含低速煤层地质环境下弹性波场多波多分量地震资料进行厂二维数值模拟研究，对人工边界反射进行了有效处理，频散效应得到了有效的压制，对几种不同激发与观测排列方式下（地面激发、低速煤层中激发以及地面观测与VSP观测）的弹性波资料进行了模型计算与分析．结果表明：低速煤层中激发时，由于煤层上下项底板介质的高速特性，其反射极性相反，在VSP地震记录上会出现煤层段记录到的波场相长干涉现象．振幅放大；地面地震记录上会出现”亮点”现象．地面激发时，地震记录上会出现“暗点”现象．而且，VSP与地面记录上，低速层中干涉后的波场与反射彼场波形展党，且存在频散效应，这些特征可能是低速煤层在地面或VSP观测地震记录上的重要指示信息，值得进一步研究与应用．
In this paper, two-dimensional numerical simulation of multi-wave and multi-component seismic data of elastic wave field in the low-velocity coal seam geological environment is carried out. The artificial boundary reflection is effectively treated and the dispersion effect is effectively suppressed. Several different excitation and observation arrangements (Ground excitation, excitation in low-speed coal seam, ground observation and VSP observation) were calculated and analyzed. The results show that due to the high velocity characteristics of the upper and lower coal beds, the reflection polarity is opposite when excited in a low velocity coal seam, and the constructive interference of wave fields recorded in the coal seam will appear on the VSP seismic record. Amplitude amplification; Ground Seismogram will appear “bright spot” phenomenon. When the ground is excited, there will be “dark spots” on the seismic records. Moreover, VSPs and ground recordings, interference wavefields in the low-velocity layer and reflection waveforms, and the presence of dispersion effects may be important indicators of low-velocity coal seams on the ground or VSP seismic records and are worth Further research and application.