逆时偏移成像技术研究进展

Progress in reverse time migration imaging

近年来,基于双程波动方程的逆时偏移方法在地震成像领域吸引了越来越多地球物理学家的关注.逆时偏移方法相对于实际油气勘探过程中被广泛应用的Kirchhoff偏移方法和单程波波动方程偏移方法,具有原理简单、成像精确且无倾角限制、适应任意复杂速度模型等诸多优点.本文首先概述了逆时偏移近三十年的发展历程,然后重点介绍了逆时偏移方法的主要新进展,内容包括波动方程数值解法的改进、成像条件的相对保幅性分析、低频噪音的消除、多波多分量逆时偏移方法、各向异性逆时偏移方法以及计算效率的提高等方面.最后对逆时偏移方法的应用现状进行了总结,并预测了逆时偏移未来的发展趋势和研究重点.

Abstract In recent years, RTM （reverse-time migration） which based on two-way wave equation, has attracted more and more attention of Geophysicists in seismic imaging fields. Compared with Kirchhoff migration and one-way wave- equation migration which are widely used in oil and gas exploration, RTM has many advantages, such as simple principle, accurate imaging, no angle limitation of one-way propagators and adapted to arbitrary velocity models. At the beginning of this paper, we review the development of RTM in the past thirty years, and then focus on the main progress in various aspects of RTM, including the numerical solution of wave equation, preserved amplitude processing of imaging conditions, low frequency imaging noise suppression, multi-wave and multi-component RTM, anisotropic RTM and improvement of the computational efficiency. Lastly, we summarize the status of the application of RTM and predict the future development trend.