基于稳定成像条件的保幅叠前深度偏移  

Amplitude-preserved prestack depth migration based on stable imaging condition.

作　　者：叶月明[1] 李振春[1] 仝兆岐[1] 杨敬磊[1] 朱绪峰[1] 

机构地区：[1]中国石油大学(华东)地球资源与信息学院,山东省东营市257061

出　　处：《石油地球物理勘探》2009年第1期28-32,共5页Oil Geophysical Prospecting

基　　金：国家自然科学基金(40474041);国家863专题(2006AA06Z206);国家973计划(2007CB209605);CNPC中青年创新基金(04E7040);中原油田博士后科研工作站和CNPC物探重点实验室中国石油大学(华东)研究室资助

摘　　要：基于炮域的保幅偏移必须应用反褶积成像条件才能达到保幅目的,但是基于阻尼型反褶积成像条件存在明显缺陷,即当分母项趋于零值的时候,会出现计算不稳定现象,严重地影响了成像质量。为此,本文基于高斯窗函数,对反褶积成像条件中的分母项进行平滑,消除了分母项中奇异值的影响,既保持了原有的反褶积型成像条件,又保持了计算的稳定性。模型试算和实际资料处理结果表明,在合适的平滑参数控制下,基于平滑函数型稳定保幅成像条件的叠前深度偏移既能提高保幅偏移的稳定性,又能较好地压制偏移噪声,获得了较好的成像结果。It should use deconvolution imaging condition that can reach the amplitude-preserved goal in amplitude-preserved migration based on shot domain, which has evident shortcomings in damping-based deconvolution imaging condition: the computation may be unstable when the denominator approaches to zero, seriously affecting the imaging quality. For that reason, the paper smoothes the denominator in deconvolution imaging condition based on Gaussian-window function, eliminating the influence of singular value in denominator, which keeps both original deconvolution imaging condition and stability of computation. It is showed by model test and practical data processing that the prestack depth migration in smoothing function-based amplitude-preserved imaging condition can both improve the stability of amplitude-preserved migration and better suppress migration noise under controlling of adequate smoothing parameter, achieving better imaging results.

关 键 词：保幅叠前深度偏移 成像条件 高斯窗函数 平滑函数 单程波方程 

分 类 号：P631.443[天文地球—地质矿产勘探] U471.15[天文地球—地质学]