中文摘要：

随着油气勘探的不断深入,叠前深度偏移技术逐渐成为解决复杂构造区域成像问题的重要手段.考虑到逆时偏移精度高但效率低,而高斯束偏移具有高效、灵活等优势,本文将逆时偏移的理论思想应用于高斯束偏移中,发展了高斯束逆时偏移,即以Kirchhoff偏移为基础,利用高斯束叠加积分计算Green函数.其不仅保留了Kirchhoff偏移的高效性和灵活性,克服了其阴影区、焦散区、单次波至等缺陷,而且还具有波动方程偏移对陡倾角的成像优势,解决了其计算量大的问题.模型和实际资料试算验证了高斯束逆时偏移方法的正确性、有效性和实用性,可以作为一项实用化技术应用于偏移成像和层析速度建模中.

英文摘要：

With the development of oil and gas exploration, pre-stack depth migration technology has become an important method in solving the imaging problem for complicated structure area. Considering that the reverse time migration has characteristics of high precision hut low efficiency while Gaussian beam migration has advantages of high efficiency and flexibility, this paper has developed a method called Gaussian beam reverse time migration by adding the idea of reverse time migration into Gaussian beam migration. On the basis of Kirchhoff migration, this method uses Gauss beam superposition integral to calculate the Green function, which not only preserves the efficiency and flexibility of Kirchhoff method without its defects such as shadow zone, caustics and single ray-path, but also has the imaging capacity similar to wave equation migration in steep-dip areas with small calculation. Examples of model and real dataset has proved the correctness, effectiveness and practicability of Gaussian beam reverse time migration, which can be used as practical technique in migration and tomography velocity modeling.