多波多分量地震资料速度扫描法转换波识别技术

多波多分量地震勘探得到的资料波场信息丰富,从中可以得到转换波信息。提出了一种速度扫描方法分离多波多分量资料中的纵波和转换波。该方法根据纵波速度及其自激自收时间,推导出相应的横波速度表达式;通过横波速度扫描，得到一系列转换波时距曲线；用得到的转换波时距曲线与多波地震数据作互相关匹配,相关程度最大时扫描横波速度最准确,也就得到了最佳的转换波波形,进而达到分离纵波和转换波的目的。利用该方法对数值模拟地震记录进行了转换波识别,取得了很好的波场分离效果。

The data acquired by multi-wave multi-component seismic exploration involves abundant wavefield information,which can be used for obtaining the information of P-SV wave.We proposed a velocity scanning method to separate the P-wave and P-SV wave from multi-wave multi-component data.In terms of P-wave velocity and zero-offset time,we derive the corresponding S-wave velocity expression.By S-wave velocity scanning,a series of P-SV time-distance curve is obtained.Then the P-SV time-distance curve is proceeded correlation match with multi-wave seismic data.When the correlation degree reaches to the maximum,the scanned S-wave velocity is most accurate,and then the best P-SV waveform is obtained,therefore,the P-wave and P-SV wave can be separated.The method is applied on the identification of P-SV wave in numerical simulated seismic records and achieves good wavefield separation result.