Subsurface scatters are sometimes masked by reflectors in seismic migration images, because the diffractions are much weaker in energy than the reflections. We propose a novel imaging method, named reflection-damped plane-wave least-squares reverse time migration (RD_PLSRTM), to enhance the scatters in the migration image. We formulate seismic imaging as an inverse problem that minimizes a weighted residual between the modeled and observed seismic data. In the proposed approach, we use the plane-wave destruction filter to separate the diffractions from the reflections in the data residual. A reflection-damped weighting matrix is then used to govern the fitting of the diffractions and the reflections, and therefore emphasize the updates of the scatters. The inverse problem is finally solved by using an iteratively reweighted least-squares (IRLS) algorithm. The proposed method provides a generalized formulation that could be reduced to conventional PLSRTM and PLSRTM of diffractions (PLSRTM_D) by using specific damping factors. We conduct imaging tests on synthetic and field data that prove the superiority of the proposed method over PLSRTM in imaging deep scatters and subsalt scatters. Compared with PLSRTM_D, it could produce high-quality images of not only the scatters but also the reflectors.

中文翻译：

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使用反射阻尼平面波最小二乘法逆时偏移增强次表面散射

地震偏移图像中的反射体有时会掩盖地下散射，因为衍射的能量比反射弱得多。我们提出了一种新的成像方法，称为反射阻尼平面波最小二乘逆时偏移（RD_PLSRTM），以增强偏移图像中的散射。我们将地震成像表述为一个逆问题，该问题最小化建模和观察到的地震数据之间的加权残差。在所提出的方法中，我们使用平面波破坏滤波器将衍射与数据残差中的反射分开。然后使用反射阻尼加权矩阵来控制衍射和反射的拟合，因此强调散射的更新。通过使用迭代重新加权最小二乘 (IRLS) 算法最终解决了逆问题。所提出的方法提供了一个通用公式，可以通过使用特定的阻尼因子将其简化为传统的 PLSRTM 和衍射的 PLSRTM (PLSRTM_D)。我们对合成和现场数据进行成像测试，证明了所提出的方法在对深部散射和盐下散射成像方面优于 PLSRTM。与 PLSRTM_D 相比，它不仅可以生成散射体的高质量图像，还可以生成反射体的高质量图像。我们对合成和现场数据进行成像测试，证明了所提出的方法在对深部散射和盐下散射成像方面优于 PLSRTM。与 PLSRTM_D 相比，它不仅可以生成散射体的高质量图像，还可以生成反射体的高质量图像。我们对合成和现场数据进行成像测试，证明了所提出的方法在成像深散射和盐下散射方面优于 PLSRTM。与 PLSRTM_D 相比，它不仅可以生成散射体的高质量图像，还可以生成反射体的高质量图像。