摘要
本文详细讨论地下复杂介质地震成像问题.当速度模型含有强横向变化时,射线场会折叠形成多次走时,在这种情况下,文中证明在保真振幅叠前深度偏移时,应当考虑所有的到时才能得到定量的像.通过实例证明,在多次走时情况下,常规的共炮集、共检波器集都存在强的假像;由此提出共角度偏移的概念.最后,在多次走时下,讨论多次偏移算子(走时、相移、振幅等)的高效重构,给出了三维叠前深度偏移的快速算法.
In this paper, we address the complex geological structures imaging problem, when the velocity macro-model is characterized by very strong lateral variations, and the ray fields may triplicate providing multi-arrivals; we demonstrated that all the multi-arrivals have to be taken into account for a quantitative migration. Furthermore, we propose a common image gather strategy in angle domain to handle the strong artifacts appear in conventional common image gathers （offset or shot domain） when multi-arrivals occurs. In the multi-arrival case, we also propose a high efficient migration algorithm for 3-D prestack multi-arrival depth migration based on the fast reconstruction algorithms for the travehime, phase rotation and amplitude of the migration operator.
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
2006年第5期1431-1444,共14页
Chinese Journal of Geophysics
关键词
叠前深度偏移
真振幅
复杂介质
Prestack depth migration, Amplitude, Complex media
