实用化的二维波动方程叠前深度偏移  

Practical methods for 2-D wave equation prestack depth migration.

作　　者：方伍宝[1] 孙建国[2] 程玖兵[3] 

机构地区：[1]南京理工大学 [2]中石化石油勘探开发研究院西部分院 [3]同济大学

出　　处：《石油地球物理勘探》2004年第1期17-23,共7页Oil Geophysical Prospecting

摘　　要：实用化的波动方程叠前深度偏移技术正在进一步发展完善之中。本文仅比较了其中四种具有代表性的方法 ,即分步傅里叶法 (SSF)、傅里叶有限差分法 (FFD)、广义屏法 (GSP)和空间—频率域有限差分法 (XWFD)。这四种方法的基本思路是 :将速度场分裂为背景场和扰动场 ;背景场的波场延拓采用相移法实现 ;扰动场的偏移成像采用不同的实现方式 ,从而构成各种方法的不同特点。文中对四种方法相应的脉冲响应进行了测试分析 ,同时用Marmousi模型数据和实测地震数据作了偏移成像处理 ,计算结果比较理想。还将波动方程偏移结果与克希霍夫积分法偏移结果进行了对比 。Practical methods for 2 D wave equation prestack depth migration are being further developed and completed.The paper only compared four representative methods,that is Split Step Fourier (SSF),Fourier Finite Difference (FFD),Generalized Screen Propagators (GSP) and Finite Difference in Space Frequency Domain (XWFD).All these methods have the following thinking: the velocity field is split into background field and disturbed field,the wavefield continuation of background field is completed by phase shift method and migrated imaging of disturbed field is fulfilled by different methods,so each method has his own characters.The paper tested and analyzed the pulse responses corresponding to four methods and migrated imaging processing was carried out by using Marmousi model and real seismic data separately at the same time,the calculated results are more ideal.The comparison of the results in these wave equation migration methods with those by Kirchhoff method is also carried out.The analyses showed the former is superior to the latter in resolution and imaging capacity for weak signal.

关 键 词：二维波动方程 叠前深度偏移技术 分步傅里叶法 SSF 广义屏法 GSF 偏移成像技术 地震勘探 

分 类 号：P631.4[天文地球—地质矿产勘探]