曲率属性根据地质体的曲率变化实现对断层、裂缝、弯曲和褶皱等构造的有效识别.本文介绍了曲率属性的基本理论,分析了二维层面曲率属性在实际资料处理中的局限性,提出了一种基于复地震道理论计算三维体曲率属性的方法,即通过计算数据体中某点的瞬时频率和瞬时波数得到视倾角分量,通过相邻道和采样点的视倾角拟合出空间曲面,从而获得该点的曲率值.将三维体曲率属性应用于实际的地震资料中,与二维层面曲率属性相比,三维体曲率属性对噪声的敏感小,在断层、裂缝等断裂构造和地层弯曲、褶皱等非断裂构造的识别、地质体几何特征的描述上更为准确有效.
Curvature attribute is based on the curvature changes of geologic bodies to delineate structures effectively, such as faults, fractures, flexures and folds. This article introduces the theory of curvature attributes, analyses the limitation of two-dimensional surface curvature attributes, and proposes a new approach to calculate three-dimensional volumetric curvature attributes. According to the theory of complex seismic traces we calculated the instantaneous frequency and instantaneous wave number of a point in the seismic data volume to obtain its apparent dip, and then we got the curvature of the point through the surface fitting by its neighboring traces and samples. We applied the three dimensional volumetric curvature attributes to practical seismic data and compared with two-dimensional surface curvature attributes. The results of the application proved that three-dimensional volumetric curvature attributes have good effect on structure identification especially in the identification of faulted structures such as faults and fractures, unfaulted structures such as flexures and folds and geometry description of geologic bodies.