基于非稳态反演的气枪阵列子波方向性反褶积（英文）
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摘要
由于气枪阵列所激发的子波具有能量强,气泡比高等优点,因此,海上地震勘探大多采用气枪阵列进行激发。但是气枪阵列具有一定的长度和宽度,加之海水虚反射的影响;致使气枪阵列子波具有明显的方向性效应,破坏了地震子波一致性,改变了反射振幅随入射角和方位角的函数关系。针对这一问题,本文提出了一种基于非稳态反演的方向性反褶积方法。该方法首先根据气枪阵列的空间配置和近场子波计算与方位角和出射角有关的远场子波。然后,基于速度模型计算不同时间地震反射在震源位置的出射角,构建方向性滤波算子。最后,采用非稳态反演方法将不同方向的地震子波整形为阵列正下方的远场子波,实现气枪阵列子波方向性反褶积处理。
Airgun arrays are widely used in marine seismic exploration because signatures excited by airgun arrays have high energy and high-peak bubble ratio, whereas the considerable length and width of the array and ghost reflections make the airgun array signature directional. As a result, the relation of the reflection amplitude with the incident and azimuth angles is variable. This means that the directivity of the airgun array results in a nonstationary wavelet and distorts the relation of the amplitude variation with the incident and azimuth angles. To remove the directivity effect, we propose a nonstationary inversion-based directional deconvolution. At first, the signature as a function of take-off angle and azimuth angle is calculated using the spatial configuration of the airgun array and the near-field signatures. Then, based on the velocity model, the time-variant take-off angles are estimated and directional filters are designed using the take-off angles. Finally, the directivity-dependent signatures are shaped to the signature right below the airgun array using nonstationary inversion in the directional deconvolution.
Airgun arrays are widely used in marine seismic exploration because signatures excited by airgun arrays have high energy and high-peak bubble ratio, whereas the considerable length and width of the array and ghost reflections make the airgun array signature directional. As a result, the relation of the reflection amplitude with the incident and azimuth angles is variable. This means that the directivity of the airgun array results in a nonstationary wavelet and distorts the relation of the amplitude variation with the incident and azimuth angles. To remove the directivity effect, we propose a nonstationary inversion-based directional deconvolution. At first, the signature as a function of take-off angle and azimuth angle is calculated using the spatial configuration of the airgun array and the near-field signatures. Then, based on the velocity model, the time-variant take-off angles are estimated and directional filters are designed using the take-off angles. Finally, the directivity-dependent signatures are shaped to the signature right below the airgun array using nonstationary inversion in the directional deconvolution.
引文
Brummit,J.G.,1989,Source directivity and its effects on resolution and signature deconvolution:First Break,7(1),17-24.
Cao,M.Q.,Ni,C.Z.,Niu,H.X.,et al.,2014,Signature directivity of air gun array in marine seismic exploration:Oil Geophysical Prospecting(in Chinese),49(2),236-238.
Duren,R.E.,1988,A theory for marine source arrays:Geophysics,53(5),650-658.
Fokkema,J.T.,Baeten,G.J.M.,and Vaage,S.,1990,Directional deconvolution in the F-X domain:SEGTechnical Program Expanded Abstracts,1673-1676.
Hubbard,T.P.,Sugrue,M.J.,Sandham,W.A.,et al.,1984,Marine source and receiver deghosting and array inversion in F-K space:46th Annual EAGEInternational Conference and Exhibition,Extended Abstracts,26.
Krail,P.,M,and Shin,Y.,1990,Deconvolution of a directional marine source:Geophysics,55(12),1542-1548.
Lee,C.,Li,Y.,Ray,S.,et al.,2014,Directional designature using a bootstrap approach:84th Annual International Meeting,SEG,Expanded Abstracts,4253-4257.
Li,G.F.,Liu,Y.,Zheng,H.,and Huang W.,2015,Absorption decomposition and compensation via a two-step scheme:Geophysics,80(6),V145-V155.
Li,G.F.,Zheng,H.,Wang,J.,et al.,2016,Inversionbased directional deconvolution to remove the effect of a geophone array on seismic signal:Journal of Applied Geophysics,130,91-100.
Loveridge,M.M.,Parkes,G.E.,Hatton,L.,et al.,1984,Effects of marine source array directivity on seismic data and source signature deconvolution:First Break,2(7),16-22.
Margrave,G.A.,1998,Theory of nonstationary linear filtering in the Fourier domain with application to time-variant filtering:Geophysics,63(1),244-259.
Parkes,G.E.,Ziolkowski,A.M.,Hatton,L.,et al.,1984 The signature of an air gun array:Computation from near-field measurements including interactionsPractical considerations:Geophysics,48(2),105-111.
Poole,G.,Davison,C.,Deeds,J.,et al.,2013,Shotto-shot directional designature using near-field hydrophone data:83th Annual International Meeting,SEG,Expanded Abstracts,4236-4240.
Roberts,G.A.,and Goulty,N.R.,1988,Directional deconvolution of the seismic source signature combined with prestack migration:First Break,6(8),247-253.
Roberts,G.A.,and Goulty,N.R.,1990,Directional deconvolution of marine seismic reflection data:north sea example:Geophysical Prospecting,38(8),881-888.
Van der Schans,C.A.,and Ziolkowski,A.M.,1983,Angular-dependent signature deconvolution:53th Annual International Meeting,SEG,Expanded Abstracts,433-435.
Zhang,C.,and Ulrych,T.J.,2007,Seismic absorption compensation:A least-squares inverse scheme:Geophysics,72(6),R109-R114.
Ziolkowski,A.M.,and Lopes,L.,1993,Directional deconvolution of marine seismic data in the frequency-wavenumber domain:55th EAGE Annual Meeting,Expanded Abstracts,P069.
Ziolkowski,A.M.,Parkes,G.E.,Hatton,L.,et al.,1982,The signature of an air gun array:Computation from near-field measurements including interactions:Geophysics,47(10),1413-1421.
Cao,M.Q.,Ni,C.Z.,Niu,H.X.,et al.,2014,Signature directivity of air gun array in marine seismic exploration:Oil Geophysical Prospecting(in Chinese),49(2),236-238.
Duren,R.E.,1988,A theory for marine source arrays:Geophysics,53(5),650-658.
Fokkema,J.T.,Baeten,G.J.M.,and Vaage,S.,1990,Directional deconvolution in the F-X domain:SEGTechnical Program Expanded Abstracts,1673-1676.
Hubbard,T.P.,Sugrue,M.J.,Sandham,W.A.,et al.,1984,Marine source and receiver deghosting and array inversion in F-K space:46th Annual EAGEInternational Conference and Exhibition,Extended Abstracts,26.
Krail,P.,M,and Shin,Y.,1990,Deconvolution of a directional marine source:Geophysics,55(12),1542-1548.
Lee,C.,Li,Y.,Ray,S.,et al.,2014,Directional designature using a bootstrap approach:84th Annual International Meeting,SEG,Expanded Abstracts,4253-4257.
Li,G.F.,Liu,Y.,Zheng,H.,and Huang W.,2015,Absorption decomposition and compensation via a two-step scheme:Geophysics,80(6),V145-V155.
Li,G.F.,Zheng,H.,Wang,J.,et al.,2016,Inversionbased directional deconvolution to remove the effect of a geophone array on seismic signal:Journal of Applied Geophysics,130,91-100.
Loveridge,M.M.,Parkes,G.E.,Hatton,L.,et al.,1984,Effects of marine source array directivity on seismic data and source signature deconvolution:First Break,2(7),16-22.
Margrave,G.A.,1998,Theory of nonstationary linear filtering in the Fourier domain with application to time-variant filtering:Geophysics,63(1),244-259.
Parkes,G.E.,Ziolkowski,A.M.,Hatton,L.,et al.,1984 The signature of an air gun array:Computation from near-field measurements including interactionsPractical considerations:Geophysics,48(2),105-111.
Poole,G.,Davison,C.,Deeds,J.,et al.,2013,Shotto-shot directional designature using near-field hydrophone data:83th Annual International Meeting,SEG,Expanded Abstracts,4236-4240.
Roberts,G.A.,and Goulty,N.R.,1988,Directional deconvolution of the seismic source signature combined with prestack migration:First Break,6(8),247-253.
Roberts,G.A.,and Goulty,N.R.,1990,Directional deconvolution of marine seismic reflection data:north sea example:Geophysical Prospecting,38(8),881-888.
Van der Schans,C.A.,and Ziolkowski,A.M.,1983,Angular-dependent signature deconvolution:53th Annual International Meeting,SEG,Expanded Abstracts,433-435.
Zhang,C.,and Ulrych,T.J.,2007,Seismic absorption compensation:A least-squares inverse scheme:Geophysics,72(6),R109-R114.
Ziolkowski,A.M.,and Lopes,L.,1993,Directional deconvolution of marine seismic data in the frequency-wavenumber domain:55th EAGE Annual Meeting,Expanded Abstracts,P069.
Ziolkowski,A.M.,Parkes,G.E.,Hatton,L.,et al.,1982,The signature of an air gun array:Computation from near-field measurements including interactions:Geophysics,47(10),1413-1421.