基于分段全变分约束的动态混合编码震源全波形反演

Dynamic hybrid encoded-source full waveform inversion based on piecewise total variation constraint

震源编码技术可以大大缩短全波形反演过程中的正演耗时,从而大大提高反演的计算效率.但是震源混叠会在反演结果中引入串扰噪声.本文将全变分约束引入全波形反演,并根据动态混合编码策略的串扰噪声特征,提出了基于分段全变分约束的全波形反演方法.全变分约束能锐化模型界面,同时压制层内随机噪声.将全变分约束与混合编码震源全波形反演方法联合,并结合分段约束策略,能在大大提高计算效率的同时,克服串扰噪声的干扰.在数值模拟部分,分别将本文方法在Marmousi模型和Overthrust模型上进行了测试,结果表明本文方法在压制多震源串扰噪声方面较常规方法具有明显的优势.

The source coding technology can greatly shorten the forward modeling time consumption in the full waveform inversion process,thereby greatly improving the computational efficiency of the inversion.However,source aliasing introduces crosstalk noise into the inversion results.In this paper,the total variation constraint is introduced into full waveform inversion,and based on the crosstalk noise characteristics of the dynamic hybrid coding strategy,a full waveform inversion method based on the piecewise total variation constraint is proposed.The total variation constraint can sharpen the model interface while suppressing random noise within the layer.Combining the total variation constraint with the hybrid coded full-waveform inversion method,and combining with the piecewise constraint strategy,the computational efficiency can be greatly improved while overcoming the interference of crosstalk noise.In the numerical tests,the proposed method is tested on Marmousi model and Overthrust model,respectively.The results show that the proposed method has obvious advantages over conventional methods in suppressing multi-source crosstalk noise.