中文摘要：

利用界面的形状或者其不连续性是基于叠后地震数据刻画断裂的两种主要方法,根据实际地震资料的特点,两种方法各有其优劣性.对于同界面形状相关的断裂刻画方法,较常用的为地震曲率属性.受实际断裂模型的制约,在曲率属性的基础上,曲率变化率表现出对断裂更强的相关性及敏感性.本文发展了以反正切函数为准线的柱面拟合法来刻画断裂,主要包括两个步骤,分别为：一、柱面直母线的拟合;二、柱面准线拟合及曲率变化率的求取.实际地震资料计算结果表明,该方法对断裂刻画的精度高于传统方法,能够揭示更多的断裂细节,特别是对于地震剖面上不易识别的小断距断裂,亦能够清晰的刻画,同时具有较高的信噪比.

英文摘要：

When using post-stack seismic data for characterizing faults and fractures,there are two different sets of seismic attributes available to choose,i.e.surface-shape-related and seismic discontinuity attributes.Depending on seismic data itself,each of them has its good points.Curvature falls into the former category and is powerful and popular in delineating faults and fractures.Based on our study,the curvature change rate is more relevant and sensitive to a faulted horizon.The new method employs the fitting of a cylindrical surface with arctan function as its directrix to characterize faults and fractures,including generatrix fitting and directrix fitting,both fittings are estimated in a least square sense.And then we calculate the curvature change rate of the directrix of the cylindrical surface.The applications of the new attribute demonstrate it can detect more subtle faults and fractures than traditional seismic attributes,especially for characterizing faults with small throws,and the results show high signal-to-noise ratio.