关于起伏地表偏移表层高频校正量计算方法的讨论

受现有速度建模技术的限制,对地震数据进行适当的近地表校正仍然是起伏地表偏移处理流程的重要一步。“面向起伏地表偏移成像的表层静校正方法”一文在这方面进行了有益的尝试,提出了只校正高频静校正量的表层校正方法和相应的高频静校正量、高频基准面计算方法。就该文中的高频静校正量和高频基准面计算方法、高频静校正量应用后表层对数据的影响等方面展开讨论,提出不同的观点,并结合一个简单模型加以说明。分析认为,高频基准面应该是实际地形的某种平滑结果;应用高频静校正量后表层对地震数据影响的中、低频分量还在,将在后续的速度建模与偏移过程中体现出来。给出了计算高频基准面和高频静校正量思路的建议。

Restricted to the existing technology of velocity modeling,the static correction for seismic data is still vital to the processing workflow of the migration from rugged topography.In the paper of “A new static correction method for the migration from rugged topography” a useful attempt was adopted,and a static correction method merely for high frequency statics,corresponding calculation methods for high frequency statics and high frequency datum were proposed.The calculation methods for high frequency statics,high frequency datum and the effect on data of their applied are discussed in this paper.We give a different opinion and illustrate with a simple model.The analysis shows that high frequency datum is some kind of smoothing result of actual landform.After the application of high frequency statics,the medium and low frequency components still have an effect on seismic data,which will be reflected in the velocity model and migration.The suggestions on how to calculate the high frequency statics and high frequency datum are proposed as well.