弹性全波形反演与逆时偏移成像

为了促进发展了几十年的弹性波成像技术实用化，准确应对速度建模精度低、地震成像分辨率低、巨量计算效率低、海量数据存储量大等“三低一大”难题，本项目拟开展弹性波成像领域的关键科学问题研究。围绕弹性全波形反演强非线性、纵横波梯度串扰、收敛性慢等关键难题，通过构建解耦纵横波梯度敏感算子、将声波测井速度进行映射得到的地震频段速度进行正则化约束及高效快速收敛技术，研发岩石物理驱动的融合声波测井信息的弹性全波形反演理论和方法；以解耦延拓理论为基础，研发以高精度弹性波场构建、能量无泄漏弹性矢量波场分离、高效非规则计算网格、无存储震源波场重构等为特色技术的弹性逆时偏移成像方法。本项目力图建立实用化弹性速度建模与偏移成像理论和方法，研发具有自主知识产权的GeoEast云平台软件模块，进一步提高油气资源地震探测的精度和效率。

In order to promote the practical application of elastic wave imaging technology, which has been developed for decades, and accurately deal with the "three low and one big" problems, such as low accuracy of velocity modeling, low resolution of seismic imaging, low efficiency of massive computation, and large storage of massive data, this project plans to carry out research on key scientific issues in the field of elastic wave imaging. In this case, the Elastic Full Waveform Inversion and Reverse-Time Migration is a revolutionary technology which meets the needs of the industry. In this project, we intend to conduct research on key scientific issues of Elastic Full Waveform Inversion and Reverse-Time Migration. To overcome the strong nonlinear problem, P- and S- wave gradient crosstalk and slow convergence of the Elastic Full Waveform Inversion, the decoupled P- and S- wave gradient, regularization constraint of the sonic logging information obtained by the velocity dispersion relationship and efficient convergence techniques will be developed. On the basis, the petrophysically-driven elastic full waveform inversion theory and method integrating sonic logging information will be built. Based on the decoupled elastic wave equation theory, the elastic reverse time migration with its own characteristics are studied, which are included the high-precision elastic wavefield construction, P- and S- wavefield separation without energy loss, efficient nonirregular computing grid, and nonstorage wavefield reconstruction. This project seeks to establish practical elastic velocity modeling and imaging theory and method, research and develop GeoEast cloud platform software module with independent intellectual property right, and further improve the accuracy and efficiency of seismic detection of oil and gas resources.