黏声介质全三维双平方根方程叠前深度偏移及其在海上数据中的应用  

Full 3Ddouble-square-root prestack depth migration in visco-acoustic medium and its application in offshore seismic data

作　　者：赫建伟 邓勇 任婷 黎孝璋 张文祥 鲁统祥 He Jianwei;Deng Yong;Ren Ting;Li Xiaozhang;Zhang Wenxiang;Lu Tongxiang(CNOOC Hainan Energy Co.LTD,Haikou,Hai-nan 570100,China)

机构地区：[1]中海油海南能源有限公司,海南海口570100

出　　处：《石油地球物理勘探》2018年第6期1210-1217,I0004,共9页Oil Geophysical Prospecting

基　　金：国家科技重大专项(2017ZX05026-005)资助.

摘　　要：海上多方位/宽方位和高密度地震数据采集可有效地提高复杂勘探区域的成像质量,但海量的地震数据对叠前深度偏移形成了较大的挑战。另外,随着勘探目标埋深增大,介质的吸收成为中深层精细成像不可忽略的因素。针对上述实际需要,首先讨论了全三维双平方根方程叠前深度偏移的基本公式。基于双平方根算子的全三维叠前深度偏移成像的优点是无需选择偏移孔径、适应炮数极多的多方位/宽方位和高密度海上地震数据、易于考虑衰减效应、便于产生方位角度道集。然后在考虑衰减补偿的稳定性的基础上,将其扩展到黏声介质中,实现了带衰减补偿的全三维叠前深度偏移。借助较大计算内存和高维快速傅里叶变换,可同时实现工区所有炮检波场的向下延拓。最后将该方法用于模型数据和海上实际数据处理,结果证明了方法的有效性。The multi-azimuths/wide-azimuth and hlghdensity seismic acquisition in marine exploration could enhance the subsurface imaging in terms of illumination and energy focusing.However,thehuge amount of shot gathers poses great challenge for seismic imaging.Besides,as the exploration target becomes deeper and deeper,the inelastic absorption affects the imaging quality of deep reservoirs.To solve these problems,we propose in this paper a full 3D double-square-root (DSR)prestack depth migration (PSDM)method in visco-acoustic medium.The full 3D DSR PSDM method has several advantages.Firstly,it does not need to select the migration aperture.Secondly,it is suitable for the multi-azimuths/wide-azimuth and high-density marine seismic data with a large number of shots. Thirdly,it can extended to the absorption medium. Fourthly,ADCIGs of all azimuths can be easily generated.With large memory and the high-dimen- sional fast Fourier transform,this method can largely improve the migration efficiency.Synthetic data and real marine data processing demonstrate the feasibility of the proposed method.

关 键 词：叠前深度偏移 黏声介质 全三维 衰减补偿 多方位/宽方位 高密度 

分 类 号：P631[天文地球—地质矿产勘探]