改进的统计滤波方法在地震数据处理中的应用及局限性

Application and limitation of improved statistical filtering method in seismic data processing

地震数据噪声压制技术有着广泛的应用需求。地震数据可以抽象地看成是由时距关系确定的地震同相轴与某种统计规律确定的随机噪声构成。以加权叠加为基础的经典统计滤波会影响地震数据中的同相轴信息,滤波效果不理想,所以需要依据地震数据的特征改进统计滤波器。统计滤波需跟踪地震同相轴,自适应地设计与区域地质特征相匹配的扁平窗函数。为此,提出一种沿同相轴方向的各向异性滤波器,在不同区域自适应地沿同相轴方向滤波,从而设计出适应地震数据变化规律的滤波器。合成数据和实际数据验证了该方法可以有效提高信噪比,并保持地震数据中同相轴的有效信息。根据信噪比、残差、误差曲线的定性和定量结果分析说明了统计滤波器应用的局限性。

Noise suppression technology of seismic data is in great demand for applications.In an abstract sense,seismic data can be considered as the composition of the seismic events determined by a certain time-distance relationship and the random noise determined by a certain statistical rule.The traditional statistical filtering based on weighted superposition often affects the event information in seismic data,which leads to unsatisfactory filtering effects.Therefore,the statistical filter should be improved according to the characteristics of seismic data.Filtering should be considered from a statistical perspective,and statistical filtering needs to track the seismic reflection events to adaptively design a flat window function that matches the geological characteristics of different regions.Therefore,we propose an anisotropic filter along the events to adaptively filters along the events in different regions,which conforms to the laws of seismic data.Then,synthetic data and real data verify the effectiveness of the proposed method in improving the signal-to-noise ratio(SNR)and retaining events.Finally,the quantitative and qualitative results of SNR,residual,and error curves are analyzed to state the application limitations of the statistical filter.