摘要
随着3D地震勘探技术的发展,对各向异性介质地震波传播理论的研究也在不断深入。不考虑HTI介质影响的动校正后的叠前CMP道集中仍存在着"正弦型"的剩余时差,传统的基于Dix时差公式的速度分析和动校正已无法满足处理的精度要求。通过借鉴统计剩余静校正的参考道互相关法和最小方差法,并结合HTI介质特征,提出了基于参考道的统计各向异性时差校正方法。提取各向异性时差并进行校正,对其叠加道的纵向分辨率的提高进行了定量分析。实验结果表明,统计各向异性剩余时差校正法消除了由HTI介质产生的剩余时差,同时也提高了纵向分辨率,从而使叠加剖面的质量得到显著提高。
With the development of 3D seismic exploration techniques,the study of seismic wave propagation theory in anisotropic media is going deeper.Without considering the impact of HTI media,prestack CMP trace gathers still remain "sinusoidal" residual moveout,the traditional velocity analysis and NMO based on Dix time difference formula can't meet the requirements of precision.By drawing from statistics residual static correction reference track cross-correlation and minimum variance method,and combining the feature of HTI media,propose a method of correction of statistical anisotropy residual moveout based on reference trace.By extracting and revising the anisotropic moveout to enhance quality of the stacked profile,and give a quantitative analysis of increases of vertical resolution of stacked trace.Experiment result shows that methods of calibration of statistical anisotropy residual moveout eliminate residual moveout caused by anisotropy,and increase the vertical resolution,and then enhance the quality of stacked profile obviously.
引文
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