复杂山区初至波层析反演静校正

Static of tomographic inversion by first breaks in complex areas

提高静校正精度是取得复杂山区良好地震成像的一个重要条件.而建立在水平折射面假设基础之上折射波静校正方法,无论是假设前提还是实际应用效果,都不适应于地表剧烈起伏,速度纵、横向变化大的复杂区.为此本文提出使用初至波层析反演静校正方法,即利用地震记录中初至旅行时反演出表层速度模型,计算出炮点和检波点的静校正量.通过正演模拟数据和实际资料的验证,很好的解决了复杂地表引起的静校正问题.

The solution of static problem in complex mountainous areas is one of the most important aspects of better seismic imaging. The refraction static method is based on the hypothesis of horizontal refraction interface. Therefore, both the precondition and the practical applications have proved its incapability for the complicated areas characterized by severely relief surface and rapidly changed velocity both laterally and vertically. This paper recommends the tomographic inversion static by first breaks, that is to say, the first breaks of seismic records are used to inverse the surface velocities and calculate the long-period static corrections and the short-period static corrections. By using it to the forward modeling and the practical seismic data, the tomographic inversion method well solves the static problem caused by complicated surface.