Abstract：The application of the reverse time migration (RTM) is still limited by its expensive computing costs and huge storage requirements although it has been more widely used in the seismic exploration with the rapid development of high-performance computing technology.In this paper,an efficient RTM method based on optimal operator boundary storage strategy is proposed.Firstly,the first-order equation is transformed into a curved coordinate system from Cartesian coordinate system to realize the conversion of velocity field from the depth domain to the vertical time domain.The RTM in the vertical time domain can reduce the vertical sampling rate,overcome the oversampling problem in high-velocity zones,and improve the computational efficiency.Secondly,based on the source wavefield approximation,an optimal operator is constructed by the approximate difference formula to replace the specific difference term,and the approximate reconstruction equation of the source wavefield is derived.This strategy only needs to store one layer of boundary wavefield,which can effectively reduce the storage of RTM.The numerical results show that the vertical time domain acoustic wave RTM method based on the optimal operator boundary storage strategy has good practicality,which can effectively reduce the storage capacity and calculation time,and accurately image complex structures.
段沛然, 谷丙洛, 李振春. 基于优化算子边界存储策略的高效逆时偏移方法[J]. 石油地球物理勘探, 2019, 54(1): 93-101.
DUAN Peiran, GU Bingluo, LI Zhenchun. An efficient reverse time migration in the vertical time domain based on optimal operator boundary storage strategy. Oil Geophysical Prospecting, 2019, 54(1): 93-101.
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