Robust adaptive polarization analysis method for eliminating ground roll in 3C land seismics  

一种稳健压制陆上三分量地震记录中面波的自适应极化分析方法(英文)

作　　者：陈海峰[1,2,3] 李向阳[1,2,3,4] 钱忠平 赵桂玲 

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [2]中国石油东方地球物理公司,河北涿州072751 [3]中国石油大学(北京)CNPC物探重点实验室,北京102249 [4]英国地质调查局

出　　处：《Applied Geophysics》2013年第3期295-304,358,共11页应用地球物理（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.41074080);the Important National Science&Technology Specific Projects(No.2011ZX05019-008)

摘　　要：To improve the data quality of converted waves, and better identify and suppress the strong ground-roll interference in three-component （3C） seismic recordings on land, we present an adaptive polarization filtering method, which can effectively separate the ground- roll interference by combining complex polarization and instantaneous polarization analysis. The ground roll noise is characterized by elliptical plane polarization, strong energy, low apparent velocity, and low frequency. After low-pass filtering of the 3C data input within a given time-window of the ground roll, the complex covariance matrix is decomposed using the sliding time window with overlapping data and length that depends on the dominant ground-roll frequency. The ground-roll model is established using the main eigenvectors, and the ground roll is detected and identified using the instantaneous polarization area attributes and average energy constraints of the ground-roll zone. Finally, the ground roll is subtracted. The threshold of the method is stable and easy to select, and offers good ground- roll detection. The method is a robust polarization filtering method. Model calculations and actual data indicate that the method can effectively identify and attenuate ground roll while preserving the effective signals.针对提高陆上转换波地震资料的品质,为了更好的识别和压制三分量地震记录中的强面波干扰,本文结合复偏振分析和瞬时极化分析,提出了一种能有效压制陆上三分量记录中强面波干扰的自适应极化滤波方法。该方法综合应用了面波椭圆平面偏振、能量强、视速度低以及频带低特征。在给定的面波时窗内低通滤波,采用依赖面波主频的滑动重叠时窗,进行复协方差本征值分解,由主特征向量建立面波模型,利用瞬时极化面积属性和面波区平均能量约束,检测和识别面波,最后自适应减去。这种方法的门槛值稳定,易于选取,适应性强,是一种稳健的极化滤波方法。模型和实际资料的试算结果,表明该方法能有效的识别和衰减面波,能较好地保护有效信号。

关 键 词：three-component （3C） adaptive polarization filtering suppressing ground roll 

分 类 号：P631.44[天文地球—地质矿产勘探]