论文部分内容阅读
三维反射地震测量已经越来越多的用于解决复杂地质区的问题。大量的资料需要有关于保持振幅和高频成分的精益求精的处理方法。我们提出一个在应用上具有高度灵活性的三维资料处理体系。在每一处理阶段中,任何野外方法所获资料都可得到同样良好的处理。叠加以前,用自动迭代式的修正法估算出地震道分布范围内的地面一致的剩余静校正量。无论预先选定的资料编排方式如何,都可以制作任何方向的叠加剖面。方法是把参与叠加的各道分成沿处理线等间隔分布的特定道集,并可以照顾到诸如走向和倾向等地质资料而赋予附带的加权系数。三维资料处理的最后一步是用基尔霍夫法或有限差分法实现三维波动方程偏移。针对准确度和计算时间,讨论了这两种方法的应用及其局限性。克希霍夫偏移法中的有限时窗问题,等价于光学中的变迹法问题。实现三维有限差分偏移的方法是,把有三个空间变量的一个偏微分方程,分成有两个空间变量的两个方程。
Three-dimensional reflection seismic surveys have been used more and more to solve complex geological problems. A lot of information is needed to keep improving the amplitude and high frequency components of the treatment. We propose a highly flexible 3D data processing system for applications. In every stage of the process, the data obtained by any field method are equally well handled. Prior to stacking, the remaining static corrections to the ground within the distribution of the traces were estimated using an automatic iterative correction. No matter how the preselected data is arranged, you can create stacked profiles in any direction. The method is to divide each participating road into specific gatherers equally spaced along the line of treatment and to give incidental weighting factors in consideration of the geological data such as the direction and tendency. The final step in 3D data processing is to use the Kirchhoff or Finite Difference methods to achieve 3D wave equation migration. In view of the accuracy and calculation time, the application of these two methods and their limitations are discussed. The problem of finite-time window in Kirchhoff’s offset method is equivalent to the problem of apodization in optics. The way to achieve three-dimensional finite difference migration is to divide a partial differential equation with three spatial variables into two equations with two spatial variables.