转换波三维初至静校正方法在SLG气区的应用

THE APPLICATION OF 3D CONVERTED WAVE FIRSTBREAK REFRACTION STATIC IN THE SLG AREA

由于转换横波的传播速度比纵波低,且其传播不受孔隙流体的影响,故其在近地表的结构和纵波亦不同,因此在转换波地震资料处理过程中,转换横波的静校正问题比纵波更为突出。利用纵波初至和转换横波初至联合来建立近地表模型、最终求取转换横波的静校正量的方法,并在SLG气区实际应用,取得了良好的效果,认为可在生产实际中推广。

Due to converted shear wave have lower velocity than P wave and the fluid in the medium have no action to converted shear wave. The near surface model for converted shear wave is different from that for P wave. The static of converted shear wave become more important and serious than P wave in converted shear wave seismic data processing. In this article,first,use firstbreak time of P wave to obtain the near surface model ; second , pick the firstbreak time difference between P wave and converted shear wave by cross correlation ; then , calculate the static of converted shear wave. We use the real 3D converted wave seismic data in the SLG area. As it shows in this paper, the problem of converted shear wave static is solved perfectly. We suggest that this method may be widely used in converted shear wave seismic data processing.