黏滞声波高斯束叠前深度偏移  

Viscoacoustic Gaussian Beam Prestack Depth Migration

作　　者：吴娟[1,2] 陈小宏[1,2] 白敏[1,2] 

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [2]中国石油大学(北京)海洋石油勘探国家工程实验室,北京102249

出　　处：《吉林大学学报（地球科学版）》2015年第5期1530-1538,共9页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金项目(U1262207);国家科技重大专项课题(2011ZX05023-005-005;2011ZX05019-006)

摘　　要：高斯束偏移不仅具有接近于波动方程偏移的成像精度,而且保留了Kirchhoff积分法高效、灵活的优点,可以对复杂介质准确成像。由于实际地下介质具有黏滞性,因此研究黏滞声波叠前深度偏移具有一定的现实意义。笔者采用高斯束偏移方法对地震数据进行吸收衰减补偿。首先给出共炮域高斯束叠前深度偏移原理;然后在此基础上推导补偿吸收衰减的表达式,校正品质因子Q引起的振幅衰减和相位畸变,实现基于吸收衰减补偿的高斯束叠前深度偏移;最后用两层模型和气云模型对偏移方法进行了测试。结果表明,在考虑地下介质的黏滞性时,黏滞声波高斯束叠前深度偏移比声波高斯束叠前深度偏移具有更高的成像分辨率。Gaussian beam migration is an effective and efficient depth migration method with its accuracy comparable to the wave equation migration and its flexibility comparable to Kirchhoff migration.The viscoacoustic prestack depth migration is of practical significance because it considers the viscosity of the subsurface media.Gaussian beam migration is used to perform seismic data compensation for frequency dependent absorption and dispersion.Gaussian beam prestack depth migration algorithms that operate on common-shot gathers are presented to derive expressions about attenuation and compensation which correct amplitude attenuation and phase distortion caused by Qin order to realize Gaussian beam prestack depth migration.The numerical modeling suggests that the viscoacoustic Gaussian beam prestack depth migration have a higher imaging resolution than the acoustic Gaussian beam prestack depth when the viscosity of the subsurface is considered.

关 键 词：高斯束 衰减补偿 黏滞声波 格林函数 叠前深度偏移 

分 类 号：P631.4[天文地球—地质矿产勘探]