结构方位滤波在体曲率属性中的应用

(1.成都理工大学“油气藏地质及开发工程”国家重点实验室,四川成都610059;2.成都理工大学地球物理学院,四川成都610059)

Yang Wei,State Key Laboratory of Oil and Gas Reservoir Geology and Exploration,Chengdu University of Technology,Chengdu 610059,China

在各向异性扩散方程的基础上,结构方位滤波通过扩散张量构建结构张量，从而控制滤波的方向和速度,实现压制噪声的同时保持地震反射同相轴的边缘信息,增强反射同相轴的连续性,突出地层间的接触关系。该方法讨论了不同类型的扩散张量对扩散方程滤波作用的影响,将高斯核和微分算子进行卷积，得到了稳健的结构张量,由此得到了计算三维结构方位滤波的方法。通过加入断层算子使结构方位滤波方程在扩散作用的同时有效保持断层构造等不连续性信息。将该方法应用于实际地震资料进行体曲率属性的计算并与中值滤波进行了比较,结果表明该方法对地震资料信噪比的提高和体曲率属性的正确提取与分析十分有效。

Structure-oriented filtering is based on anisotropic diffusion equations,which controls the direction and speed of filtering through constructing diffusion tensor by structure tensor.Structure-oriented filtering suppresses the noise while maintaining the edge information of seismic reflection event.In addition,it can enhance the continuity of seismic reflection event and highlight the contact relationship between strata.According to the discussion on the impact of different types of diffusion tensor on the filtering effect of diffusion equations,robust structure tensor was obtained by the convolution between Gaussian kernel and first-order partial differential operator,which introduced the method of calculating 3D structure-oriented filtering.Structure-oriented filtering equation adds the fracture operator for diffusion while maintaining discontinuous information such as fault structures.This method was applied to practical seismic data for the calculation of volumetric curvature attributes and was compared with median filtering.The results prove that the method is effective to improve signal-to-noise ratio of seismic data,as well as correctly extract or analyze volumetric curvature attributes.