标志层控制的静校正方法在巨厚黄土塬地区的应用

A marker-layer-controlled static correction method in thick loess tableland

处理巨厚黄土塬地区的地震资料时,常规静校正方法难以解决复杂的中、长波长静校正问题,给地震资料处理成果的构造形态和信噪比带来不利影响。为此,分析了常规静校正方法效果不佳的原因;开展了针对巨厚黄土塬地区的静校正处理方法的研究,提出了标志层控制的静校正方法。该方法包括基于标志层构造形态控制的高程静校正、基于初至波叠加的中波长静校正和基于标志层修正的剩余静校正3个递进式的步骤,依次用于消除长波长静校正量、中波长剩余静校正量和短波长剩余静校正量。探讨了上述递进式静校正方法的技术流程和关键环节;参照巨厚黄土塬地区地震勘探实际情况,正演模拟含水平层和不含水平层的二维数值模型数据;分别采用标志层控制的静校正方法、层析静校正等方法进行处理,结果表明标志层控制的静校正方法在一定程度上较好地解决了巨厚黄土塬地区中、长波长静校正不准确的问题。对鄂尔多斯盆地某巨厚黄土塬地区的实际地震资料分别采用标志层控制的静校正方法和层析静校正方法进行试处理,结果显示采用标志层控制的静校正方法得到的处理成果可靠性和品质明显更高,弥补了常规静校正处理技术的不足。

Solving complex,middle-to-long wavelength static corrections in thick loess tableland via the conventional static correction method is problematic due to the destructive effects on both the structural morphology and the signal-to-noise ratio(SNR)of the seismic data processing results.This study proposes a new marker-layer-controlled static correction method to resolve the static correction obstacles in thick loess tableland and consists of three progressive steps.First,elevation static correction based on the control of marker layer structures is designed to eliminate long-wavelength static.Next,a middle-wavelength residual static correction,based on first arrival stacks,is designed to eliminate residual middle-wavelength static.Finally,a surface-consistent residual static correction based on marker layer correction is designed to eliminate residual short-wavelength static.The method was applied to 2D numerical simulation data and actual seismic data from the thick loess tableland in the Ordos Basin.The results suggest that this marker-layer-controlled static correction method can eliminate the significant static correction problem in thick loess tableland and improve the reliability and quality of processing results to overcome the limitation of conventional static correction.