面向地质目标的地震偏移成像进展

面向地质目标体的成像技术将局部区域作为成像目标, 获得深层目标构造或特殊地质构造如高陡构造、盐下构造、小尺度构造的精细成像结果。总结了面向地质目标的地震偏移成像方法的研究进展, 归纳出面向地质目标体的成像方法包括了数据选择类方法和模型选择类方法。数据选择类方法利用地震特征波对特殊地质构造进行成像, 主要包括多次波成像、绕射波成像和回折波成像等; 模型选择类方法对局部目标区域进行精确成像, 通常可大幅度提高计算效率, 主要包括基于模型选择的地震干涉法、数据基准面重构法、面向地质目标的CFP成像方法、局部目标成像法、声弹耦合波场延拓法和成像域最小二乘偏移法等。面向地质目标的地震偏移成像技术总体发展趋势是从偏移成像到反演成像, 模型选择类方法与数据选择类方法融合发展, 并与人工智能技术结合, 可实现地质目标地震靶向成像。

Geological target-oriented imaging technology aims to improve the imaging of deep target layers and special geological formations, such as highly steep structures, sub-salt structures, and small-scale structures, by selecting local areas as the imaging target.We summarized the research progress in seismic migration imaging methods for geological targets.Geological target-oriented migration methods can be classified into data and model selection methods.Data-selection imaging methods use characteristic seismic waves to image special geological structures, including data-selected prismatic wave imaging, multiple imaging, diffracted wave imaging, and diving wave imaging methods.The model-selection imaging methods, which mainly include data datum reconstruction methods, target-oriented CFP imaging methods, local target imaging methods, acoustic-elastic coupled wavefield continuation methods, and least-squares migration in the imaging domain, selected local target regions for accurate imaging, which substantially improved the computational efficiency.The general trend in geological target-oriented seismic migration technology ranges from migration-based imaging to inversion-based imaging and integrating model selection and data selection types with artificial intelligence technology to achieve seismic target imaging for geological targets.