An illumination‐compensated Gaussian beam migration for enhancing subsalt imaging
An illumination‐compensated Gaussian beam migration for enhancing subsalt imaging
复制标题
DOI：
10.1111/1365-2478.13117
复制
发表时间：
2021-06
影响因子：
2.6
通讯作者：
Shaoyong Liu;Zhe Yan;Wenting Zhu;B. Han;H. Gu;Shanzheng Hu
中科院分区：
文献类型：
--
作者：
Shaoyong Liu;Zhe Yan;Wenting Zhu;B. Han;H. Gu;Shanzheng Hu
地球地下的地震图像对于石油和天然气勘探是必不可少的。高斯波束偏移由于其灵活性和实现效率而被广泛应用于地震成像。然而，经典的高斯波束偏移在盐下等复杂构造中的实际应用受到限制，因为这些地区的地震照明较差。在最小二乘偏移的框架下，提出了一种照明补偿高斯光束偏移方法，有效地增强了盐下成像。提出了一种基于高斯光束玻恩模型和偏移的点扩展函数估计方法，该方法可以在局部波数域有效地实现照明补偿。作为最小二乘偏移的目标，所提出的照明补偿高斯束偏移在盐下区域产生真振幅图像，这有利于盐下构造的地震解释。所提出的方法的总计算成本包括一个Born建模过程和两个传统的高斯光束偏移，因此它比需要多次迭代的经典最小二乘偏移更有效。数值算例表明了自适应策略的有效性，在盐下目标油气勘探中具有一定的应用潜力。
Seismic images of Earth's subsurface are essential for oil and gas exploration. Gaussian beam migration is popular for seismic imaging owing to its flexibility and efficiency of implementation. However, the practical use of classic Gaussian beam migration is limited for complicated structures such as subsalt because of poor seismic illumination in those areas. We propose an illumination‐compensated Gaussian beam migration under the framework of least‐squares migration, enhancing the subsalt imaging effectively. A novel scheme based on the Born modelling and migration of Gaussian beam is developed to estimate the point spreading function, with which the illumination compensation can be efficiently implemented in the local wavenumber domain. As the aim of least‐squares migration, the proposed illumination‐compensated Gaussian beam migration produces true‐amplitude images in subsalt areas, which facilitates the seismic interpretation of subsalt structures. The total computational cost of the proposed method includes one Born modelling process and two conventional Gaussian beam migrations, and thus it is much more efficient than the classic least‐squares migration which requires multiple iterations. Numerical examples have demonstrated the effectiveness of the adaptive strategies, manifesting applicable potential in oil and gas exploration of subsalt targets.