基于AVO正演模拟的自由表面多次波压制方法

Free-surface multiple wave suppression method based on AVO forward simulation

针对SRME和Radon变换压制自由表面多次波的近道多次波残留和伤害有效波等问题,主要采用基于AVO属性分析的多次波剔除法对近道多次波进行压制,该方法在迭代更新过程中,受近道多次波影响容易出现更新误差,同时迭代更新降低计算效率.本文对基于AVO属性分析的多次波剔除法进行改进,利用中远道地震数据进行约束,通过AVO正演模拟构建有效波的AVO属性抛物线,进而对近道多次波进行压制.该方法在构建有效波AVO属性抛物线过程中,无需迭代更新,提高了计算效率.同时该方法在多次波压制过程中不受多次波的影响.由模型测试及实际地震资料应用效果证明,本文方法能够较好的压制自由表面多次波,该方法为油气田进一步精细勘探开发提供可靠保障.

This work focuses on suppressing the near-gather multiple wave residuals and damaged effective waves of free-surface multiple waves by SRME and Radon transform.In previous work,the near-gather multiple waves are suppressed by multiple wave tick division based on Amplitude Variation with Offset(AVO)attribute analysis.During the iterative updating process of this method,the update error tends to appear due to the effect of near-gather multiple waves,and the iterative updating reduces the calculation efficiency.This paper improves the multiple wave tick division based on AVO attribute analysis.We use the middle-and far-gather seismic data to constrain,and construct the AVO attribute parabola of the effective waves by AVO forward simulation;then suppress the near gather multiple waves.During the process of constructing effective wave AVO attribute parabola,this method does not need iterative updating,and improves the calculation efficiency.At the same time,the method is not affected by the false appearance of multiple waves in the near gather,and the effect of multiple wave suppression is improved.Tests on models and real seismic data prove that this method can suppress multiple waves of free-surface better,and provides a reliable guarantee for further fine exploration and development of oil and gas fields.