基于反射波层拉平的绕射波分离与成像方法

在碳酸盐岩缝洞储集体为主要地质目标的探区,可以通过绕射波分离与成像来提高对溶洞、裂缝等特殊异常体的刻画精度。基于常规的地震资料处理模块,提出了一种基于反射波层拉平的绕射波分离与成像新方法。利用空间属性建立的共深度点CDP与炮集中各道记录的一一对应关系,完成将叠加数据体层位拉平时间信息映射到叠前炮集中各道记录上,进行叠前炮记录的反射波组拉平处理；在层拉平的基础上根据炮集记录中反射波与绕射波同相轴轨迹的规律性几何差别,采用FK滤波等技术将强反射波分离出去。介绍了关键处理技术,给出了详细的处理流程,并展示了针对物理模型观测数据和实际三维地震资料的应用效果。

 In exploration zones where carbonate fracture-cave reservoirs become primary geological targets,diffraction wave imaging are applied to improve the precision in characterizing geological bodies such as the caves and fractures.Based on conventional seismic data processing modules,a method for diffraction wave separating and imaging based on horizon-flattening of reflection waves is proposed.The principle of this method is based on the natural geometry differences between diffraction and reflection events in shot gathers.Due to the one-to-one correspondence between CDP and trace record in shot gathers,the time information of flattened horizons in stack volume can be mapped to trace record in prestack shot gathers.The strong reflection waves,which are already flattened,can be separated by techniques such as F-K filter.Besides the key technology and processing workflow of diffraction imaging,we also displays its application in synthetic data from seismic physical modeling as well as real seismic data.