优化变分模态分解方法消除强反射影响——以东营凹陷沙四段滩坝砂目标处理为例

Elimination of strong reflection influence based on optimized variational mode decomposition method:a case study of the target processing of beach bar sand of Es4 in Dongying Sag

东营凹陷沙四段纯上与纯下亚段之间的分界面为强地震反射,受其屏蔽作用,纯下亚段滩坝砂储层地震反射弱。为了有效压制强反射屏蔽层影响,应用优化变分模态分解(VMD)技术,将目标层地震信号分解成多频带、不同波形特征的分量。强屏蔽层信息能量强、频率低,多集中在第一分量。对强信号分量进行剥离,再重构余量信息,可凸显下伏储层有效信号。理论模型测试与实际资料应用表明,与传统的经验模态分解方法(EMD)相比,该方法具有分辨率高、分解完备、避免模态混叠效应等优点,在相似条件地区具有一定的推广价值。

Affected by the shielding effect of the interface between Chunshang submember and Chunxia submember of Es4 in Dongying Sag,the seismic reflections of the beach bar sand reservoir in Chunxia submember are weak.Optimized variational mode decomposition technology was used to decomposethe target layer seismic signals into multi-band components with different waveform features to suppress the influence of the strong reflection shielding effectively.Strong reflection information with strong energy and low frequency,mostly concentrate in the first component.Through stripping strong signal components and reconstructing residual information,the effective signals of underlying reservoirs can be strengthened.Theoretical model test and the application in real data demonstrated that the method has higher resolution,more complete decomposition and avoids modal aliasing effect compared with conventional empirical mode decomposition method(EMD).It is worth applying to the regions with similar conditions.