基于保幅拉东变换的多次波衰减  

Multiple attenuation based on amplitude preserving Radon transform

作　　者：王保丽[1] M.D.Sacchi 印兴耀[1] 张广智[1] 

机构地区：[1]中国石油大学(华东)地球科学与技术学院,青岛266580 [2]University of Alberta,Edmonton T6G 2G7

出　　处：《地球物理学报》2014年第6期1924-1933,共10页Chinese Journal of Geophysics

基　　金：国家科技重大专项(2011ZX05009);国家自然科学基金(41204085);山东省自然科学基金(ZR2011DQ013);中央高校基本科研业务费专项资金(13CX02040A);中国石化地球物理重点实验室(WTYJY-WX2013-04-07)联合资助

摘　　要：为在去除多次波时有效保护地震一次反射波数据的AVO现象,给后续反演、解释提供准确的地震数据,本文提出了一种基于保幅拉东变换的多次波衰减方法,该方法是对常规抛物拉东变换的修改,把常规的稀疏拉东变换在拉东域分成两部分:一部分用于模拟零偏移距处的反射波能量,增加的另一部分用于模拟反射波振幅的AVO特性.该方法不仅考虑了反射波同相轴的形状,还考虑了反射波同相轴振幅幅度的变化,从而可把反射波信息进行有效转换,进而有利于多次波的消除,更好地恢复有效波的能量.在把地震数据由时间域转换到拉东域时,本文采用了IRLS算法实现保幅拉东算子的反演.模型数据和实际地震道集的试算分析表明,与常规拉东变换相比,保幅拉东变换在去除多次波的同时可有效保护一次反射波的AVO现象.Classical Radon transform cannot preserve the amplitude versus offset（AVO）phenomena of primary when eliminating multiples,the remnant energy of multiples and the amplitude distortion of the primary will have great impact on the future seismic inversion and seismic interpretation.In order to solve these problems,an algorithm has been developed to model reflections with AVO via the amplitude preserving Radon transform.The algorithm is a modification of the classical sparse Radon transform and splits the seismic gather into two Radon gathers：one gather models the strength of the reflections at zero offset,the other one adds capability to model the AVO signature.The algorithm not only considers the shape of events as parabolas but also the energy variation of events when performing the Radon transform.It can effectively transforms the reflections to the Radon domain,easily eliminate the multiples and more accurately get the primaries.The new amplitude preserving Radon operator is inverted using the Iterative Reweight Least Square（IRLS） algorithm.Our synthetic and real data examples show an improvement with respect to the classical sparse Radon transform at the time of estimating primaries with reduced amplitude distortion and preserved AVO phenomena.

关 键 词：多次波衰减 AVO 拉东变换 保幅 

分 类 号：P631[天文地球—地质矿产勘探]