摘要
上行波叠前深度偏移是提高非零井源距VSP地震资料成像精度的主要途径之一。从二维各向同性介质中的弹性波动方程出发,在交错网格空间中推导了弹性波场逆时延拓的高精度有限差分算子,给出了弹性波场逆时延拓的最佳匹配层吸收边界条件,从时间一致性准则出发,通过求解程函方程获取VSP地震资料逆时偏移的成像条件,在此基础上实现了非零井源距VSP多分量地震资料联合逆时深度偏移。理论模型与实际资料均得到了高质量的成像结果。
The depth migration before the wave superposed plays an important role in updating the imaging precision of seismic data of vertical seismic profile（VSP） with non-zero offset.The paper derived a reverse-time propagation and high precision finite difference operator of elastic wave field in staggered grids by applying the elastic wave equations in 2-D isotropic media,and the absorbing boundary conditions of perfectly matched layer（PML） applicable to reverse-time propagation of elastic wave field was also given in the paper.Based on the consistent principle of down-going and up-going waves,the imaging condition was computed by solving the eikonal equations.On the basis of above techniques,a united reverse-time depth migration algorithm of VSP multi-component seismic data with non-zero offset was developed.The high quality imaging results were obtained by the theoretical model or field data processing.
出处
《山东科技大学学报（自然科学版）》
CAS
2010年第2期1-7,共7页
Journal of Shandong University of Science and Technology(Natural Science)
基金
国家自然科学基金项目(40804021)
国家自然科学基金重点项目(40839901)
国家重点基础研究发展计划("973"计划)项目(2009CB219603)
关键词
VSP
非零井源距
逆时偏移
有限差分
边界条件
成像条件
vertical seismic profile（VSP）
non-zero offset
reverse-time migration
finite difference
boundary condition
imaging condition
