牟海波,何兵寿

• 1:中国海洋大学海底科学与探测技术教育部重点实验室

摘要(Abstract)：

波动方程逆时偏移是目前比较精确的基于波动理论的深度域偏移成像方法,但逆时偏移成像条件的运用会产生低频噪音,影响成像质量及层位的准确性。依据低频噪声的产生机理,运用交错网格有限差分法求取各向同性介质中的地震波场,通过对比炮点与检波点波场在不同频率条件下的互相关成像特征,分析其子波频率与周期差异(或时移)条件下逆时偏移成像对层位解释精度与低频噪音产生的影响,提出了改进的时移逆时偏移成像层位校正方法和低频噪声压制策略。数据算例表明,改进后的时移逆时偏移成像有效的压制了低频噪声,成像层位准确。

关键词(KeyWords)： 各向同性介质;逆时偏移;成像层位校正;低频噪声

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金项目(编号:41174087;41204089);; 国家科技重大专项项目(编号:2011ZX05005-005);; 863计划项目(编号:2013AA064201)

作者(Author): 牟海波,何兵寿

参考文献(References)：

• [1]Whitmore,N D.,Iterative depth migration by backward time propa-gation.53rd Annual International Meeting,SEG,Expanded Abstracts,1983,382-385.
• [2]Loewenthal D,Mulfti I.R.,Reverse time migration in spatial fre-quency domain.Geophysics,1983,46,627-635.
• [3]Mc Mechan G A.Migration by extrapolation of time dependent bound-ary values.Geophysics,1983,31,413-420.
• [4]Chang,W F,and G A.Mc Mechan,Reverse-time migration of offsetVSP data using the excitation time imaging condition:Geophysics,1986,51,67-84.
• [5]Chang,W F,and G A.Mc Mechan,Elastic reverse-time migration:Geophysics,1987,52,1367-1375.
• [6]Claerbout,J F.,Imaging the Earth’s interior.Blackwell ScientificPublications,1985.
• [7]何兵寿,张会星,魏修成,等.双程声波方程叠前逆时深度偏移的成像条件.石油地球物理勘探,2010,45.
• [8]常海明,何兵寿,杨佳佳等,逆时偏移中的归一化加权互相关成像条件及应用.中国煤炭地质,2014,26.
• [9]杨绍伟,何兵寿,杨佳佳.弹性波逆时偏移子波拉伸校正[J].中国煤炭地质,2016,28(2):61-67,77.
• [10]郭念民,等,高阶拉普拉斯算子逆时偏移低频噪声去除方法.石油物探,2013,52.
• [11]韩文功,王江川,李振春,等,基于Poyinting矢量和方向行波波场分离的逆时偏移成像条件[J].地球物理学进展,2015,30.
• [12]Chen,T.,B.S.He,A normalized wavefield separation cross-corre-lation imaging condition for reverse time migration based on Poyntingvector,APPLIED GEOPHYSICS,11,2014.
• [13]Adel Khalil,James Sun,Yu Zhang and Gordon Poole,CGG,RTMnoise attenuation and image enhancement using time-shift gathers.SEGHouston Annual Meeting,2013.
• [14]Xu,S.,F.Chen,B.Tang,and G.Lambare,Noise removal by migration of time-shift images.2014,Geophysics,79,105-111.
• [15]Xue Z.G.,Sergey Fomel,and Junzhe Sun,RTM interpolation using time-shift gathers.SEG New Orleans Annual Meeting,2015.