摘要
山前带深度域速度建模由于采集数据的信噪比低和道间时差大而困难重重。由于叠前深度偏移的同相叠加作用,基于初始模型得到的共成像点道集具有比CMP道集更高的信噪比,并且共成像点道集上残存的剩余时差可以用于通过层析反演的方式来全局更新速度模型,适用于山前带深度域模型的迭代更新。共成像点道集层析速度反演还非常适用于非水平地表下的速度估计。在前人研究的基础上,进行了共成像点道集层析速度反演方法研究,并且用三维SEG盐丘模型和某山前带实际数据进行了测试。结果表明,基于共成像点道集的层析速度反演建模方法能够提高复杂山前带地震数据成像处理中速度模型的精度。
Depth-domain velocity modeling in foothill area is difficult because of the low S/N and large moveout between gathers.Common imaging gathers(CIGs) have higher S/N than CMP gathers for the in-phase stack effect of prestack depth migration.Meanwhile,the residual moveout on CIGs can be used to wholly update the depth velocity model by tomography in foothill area.Tomography velocity inversion based on CIGs is very suitable for the velocity estimation of rugged topography.On the basis of previous research,the method of CIGs tomography velocity inversion was tested on 3-D SEG salt dome model and real data from foothill area.The results show that tomography velocity inversion based on CIGs can improve the precision of depth velocity model in complicated foothill area.
出处
《石油物探》
EI
CSCD
北大核心
2012年第6期590-597,536,共8页
Geophysical Prospecting For Petroleum
基金
中国石油化工股份有限公司科技开发部"叠前深度成像技术研究"(P10044)项目资助
关键词
层析速度反演
速度建模
山前带地震勘探
共成像点道集
叠前深度偏移
tomography velocity inversion
velocity model building
piedmont seismic exploration
common imaging gathers
prestack depth migration
