最小平方逆时偏移真振幅成像  

True-amplitude imaging based on least-squares reverse time migration

作　　者：郭振波[1] 李振春[1] 

机构地区：[1]中国石油大学(华东)地球科学与技术学院,山东青岛266580

出　　处：《石油地球物理勘探》2014年第1期113-120,303,共8页Oil Geophysical Prospecting

基　　金：国家自然科学基金(40974073);国家"863"课题(2011AA060301);中央高校基本科研业务费专项资金(13CX06014A)联合资助

摘　　要：针对常规逆时偏移算法具有较强的低频噪声、对观测系统要求较高、较难进行透射损失补偿等问题,本文在构建线性化波动方程算子(反偏移算子)的基础上,详细推导了最小平方逆时偏移迭代算法,在反演的理论框架下解决了上述问题的影响,实现了真振幅成像。通过简单多层介质模型及复杂Marmousi模型试算,验证了最小平方逆时偏移在真振幅成像方面的优势。实验结果表明,此法不仅具有更高的成像分辨率,而且还能有效地压制成像噪声。Conventional reverse time migration(RTM) has disadvantages such as low frequency imaging, heavy noise,high requirements for acquisition, lack of compensating transmission losses and etc. In this paper,we propose a method for true-amplitude imaging based on least-squares reverse time migration.We treat the true-amplitude imaging as a linear inversion problem.Firstly,we derive the linearized wave propagation operator which is also called de-migration operator,and then we do some theoretical derivation on least-squares reverse time migration(LSRTM).Numerical tests on a multilayer model and Marmousi model prove that LSRTM obtains true-amplitude imaging with higher imaging resolution than conventional reverse time migration,and the noise was also well suppressed.

关 键 词：逆时偏移 真振幅 最小平方偏移 线性反演 

分 类 号：P631[天文地球—地质矿产勘探]