叠前散射波形态滤波分离方法

对于渤中A凝析气田深层变质岩潜山内幕，常规基于反射波处理的地震资料信噪比低、成像品质差，难以有效预测内幕裂缝储层展布规律。而散射波场信息能够刻画地下非均质地质体，较好地反映潜山内幕裂缝、断裂。为此，提出了一种基于数学形态学滤波的叠前散射波分离方法。通过叠前共炮检距域道集分析，确定散射波与反射波的形态特征差异，即时距关系差异，并利用这一差异构建直线形结构元素，沿空间方向做形态滤波，得到反射波。将反射波从原始波场中减去，就获得了散射波。模型测试结果表明，基于形态滤波的叠前散射波分离方法得到了相对完整的散射波场，散射波提取精度高，有效改善了复杂地质体的成像效果；实际资料应用表明，散射波成像结果提升了潜山内幕裂缝储层表征效果，为渤中A凝析气田井位部署提供了技术支持。

Pre-stack scattered wave separation method based on morphological filtering

Inside the deep metamorphic buried hill in the BZ-A condensate gas field，conventional seismic data based on reflected wave processing has a low signal-to-noise ratio and poor imaging quality. Thus, it is difficult to effectively predict the distribution of inner fractured reservoirs. Scattered wave field information can describe the underground heterogeneous geological bodies，which can well indicate the development of cracks and faults inside a buried hill. In view of this，the paper proposes a pre-stack scattered wave separation method based on mathematical morphological filtering. Through a pre-stack common-offset gather analysis, the difference between the morphological characteristics of the scattered wave and the reflected wave is determined, namely the time-distance relationship difference, and this difference is used to construct linear structural elements. Then, the reflected wave is obtained by morphological filtering in the spatial direction, and the scattered wave is obtained by subtracting the reflected wave from the original wave field. The model test results show that the pre-stack scattered wave separation method based on morphological filtering achieves a relatively complete scattered wave field with high precision and effectively enhances the imaging quality of complex geological bodies. The application of field data shows that the scattered wave imaging results improve the characterization effect of fractured reservoirs inside buried hills and provide technical support for the deployment of well locations in the BZ-A condensate gas field.