基于波动方程的炮检点二次定位方法
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摘要
在陆上地震勘探中,由于地表条件、人员疏忽等因素的影响会出现炮点定位不准确的情况;海底电缆施工过程中,由于洋流等因素的影响会使检波点的实际位置与预设位置不同,这些情况严重影响了后续的地震资料处理工作,因此需要对炮点或检波点进行二次定位。
基于波动方程的炮点二次定位参考了常规地震偏移成像技术,将排列接收到的波场反向外推,使波场逐步收敛,最终波场收敛到炮点位置,以此来实现炮点二次定位。在具体实现中需要在地面划分网格,然后应用克希霍夫积分法反向外推波场,获得网格点的能量值,能量最高的网格点便是炮点位置。为了提高运算速度同时保证定位精度,在划分网格时需要先粗分网格,求得网格点能量值,然后在能量高的网格点区域重新细分网格,通过细分网格点的能量值来确定出炮点位置。在炮点二次定位中利用的主要是直达波的波场信息,因此在预处理时,需要突出直达波压制干扰波。文章分析了在不同信噪比下的波场收敛情况,在模型实验中信噪比为1.25时仍能准确实现炮点二次定位。波场外推的速度是炮点二次定位的一个重要参数,在选取速度时,以当地的地层速度为基准,在粗分的网格中进行速度扫描分析,获得最佳的波场收敛速度,然后用其进行波场外推,求得网格点的能量值,实现炮点二次定位。
检波点二次定位主要应用于海底电缆。在海底检波点二次定位中,炮点位置已知而检波点位置未知,因此需要从多个炮点位置正向外推波场,使波场逐步延拓到检波点,以此来获得检波点的位置。在具体实现中需要从原始地震资料中抽取共检波点道集,然后在海底面划分网格,应用克希霍夫积分法正向外推波场获得网格点的能量值,能量高的网格点为检波点的真实位置。网格的划分原则与炮点二次定位一样,需要先粗分后细分。海底检波点二次定位中,同样选用直达波作为主要的波场信息,而直达波是通过海水传播到海底的,因此,波场外推的速度选用海水层的速度。
基于波动方程的炮检点二次定位在模拟和实际地震资料处理中都得到了良好的效果,验证了这种方法的可行性。
There are lots of factors such as terrain configuration and people’s neglect which can influence the positioning of shotpoint for inshore seismic exploration. The real position of receiver is different from the designed for ocean bottom cable because of the influences such as ocean current. These factors seriously affect the sequent processing of seismic date, so it’s necessary to reposition the shotpoint and receiver.
The secondary positioning of shot point utilizes the technology of seismic migration. The wave field data is extrapolated inversely which is accepted by the receiver, at last the wave field will be converged the position where the shot point is. After dividing grids on land surface, the wave field will be extraploated depends on the kirchhoff integration, then the wave field will be converged to the grids. The gird with high energy is the position where the shot point is. The gird’s interspacing is large when deviding the grid for the first time, then decrease the distance between the grids. Thus, the arithmetic can speed up, and the accuracy can be guaranteed. The direct wave is most important for the secondary positioning of the shot point. So the direct wave should be retained and the disturbing wave should be rejected. The paper analysises the constriction of wave field in different signal to noise ratio, the real position of the shot point can be found out for the simulating data when the signal to noise ratio is 1.25. The velocity of wave field extrapolation is important to the accuracy of the secondary positoning of shot point. The velocity bases on the formational velocity and scans in the grids when the interspacing of grids is large. When the velocity is confirmed, using the velocity to extrapolate the wave field to confirm the position of the shot point.
The secondary positioning of receiver which is used for ocean bottom cable is different from the secondary positioning of shot point. Because the position of shot point is known, the wave fields can be extrapolated from lots of shot points, at last they all reach the position of receiver. Thus, the position of the receiver can be found out. The first step is dividing grids on the sea floor, then with the help of kirchhoff integration, the energy of the grids comes out, the grid with high energy is the position of the receiver. The rule of the dividing grid is same to the shot point. The direct wave is the most important information in the second positioning of receiver, and the direct wave propagates through the sea water. So the velocity should be the same to the velocity of the sea.
Both the simulating and real data results confirm that the secondary positioning of shot point and receiver is feasible.
基于波动方程的炮点二次定位参考了常规地震偏移成像技术,将排列接收到的波场反向外推,使波场逐步收敛,最终波场收敛到炮点位置,以此来实现炮点二次定位。在具体实现中需要在地面划分网格,然后应用克希霍夫积分法反向外推波场,获得网格点的能量值,能量最高的网格点便是炮点位置。为了提高运算速度同时保证定位精度,在划分网格时需要先粗分网格,求得网格点能量值,然后在能量高的网格点区域重新细分网格,通过细分网格点的能量值来确定出炮点位置。在炮点二次定位中利用的主要是直达波的波场信息,因此在预处理时,需要突出直达波压制干扰波。文章分析了在不同信噪比下的波场收敛情况,在模型实验中信噪比为1.25时仍能准确实现炮点二次定位。波场外推的速度是炮点二次定位的一个重要参数,在选取速度时,以当地的地层速度为基准,在粗分的网格中进行速度扫描分析,获得最佳的波场收敛速度,然后用其进行波场外推,求得网格点的能量值,实现炮点二次定位。
检波点二次定位主要应用于海底电缆。在海底检波点二次定位中,炮点位置已知而检波点位置未知,因此需要从多个炮点位置正向外推波场,使波场逐步延拓到检波点,以此来获得检波点的位置。在具体实现中需要从原始地震资料中抽取共检波点道集,然后在海底面划分网格,应用克希霍夫积分法正向外推波场获得网格点的能量值,能量高的网格点为检波点的真实位置。网格的划分原则与炮点二次定位一样,需要先粗分后细分。海底检波点二次定位中,同样选用直达波作为主要的波场信息,而直达波是通过海水传播到海底的,因此,波场外推的速度选用海水层的速度。
基于波动方程的炮检点二次定位在模拟和实际地震资料处理中都得到了良好的效果,验证了这种方法的可行性。
There are lots of factors such as terrain configuration and people’s neglect which can influence the positioning of shotpoint for inshore seismic exploration. The real position of receiver is different from the designed for ocean bottom cable because of the influences such as ocean current. These factors seriously affect the sequent processing of seismic date, so it’s necessary to reposition the shotpoint and receiver.
The secondary positioning of shot point utilizes the technology of seismic migration. The wave field data is extrapolated inversely which is accepted by the receiver, at last the wave field will be converged the position where the shot point is. After dividing grids on land surface, the wave field will be extraploated depends on the kirchhoff integration, then the wave field will be converged to the grids. The gird with high energy is the position where the shot point is. The gird’s interspacing is large when deviding the grid for the first time, then decrease the distance between the grids. Thus, the arithmetic can speed up, and the accuracy can be guaranteed. The direct wave is most important for the secondary positioning of the shot point. So the direct wave should be retained and the disturbing wave should be rejected. The paper analysises the constriction of wave field in different signal to noise ratio, the real position of the shot point can be found out for the simulating data when the signal to noise ratio is 1.25. The velocity of wave field extrapolation is important to the accuracy of the secondary positoning of shot point. The velocity bases on the formational velocity and scans in the grids when the interspacing of grids is large. When the velocity is confirmed, using the velocity to extrapolate the wave field to confirm the position of the shot point.
The secondary positioning of receiver which is used for ocean bottom cable is different from the secondary positioning of shot point. Because the position of shot point is known, the wave fields can be extrapolated from lots of shot points, at last they all reach the position of receiver. Thus, the position of the receiver can be found out. The first step is dividing grids on the sea floor, then with the help of kirchhoff integration, the energy of the grids comes out, the grid with high energy is the position of the receiver. The rule of the dividing grid is same to the shot point. The direct wave is the most important information in the second positioning of receiver, and the direct wave propagates through the sea water. So the velocity should be the same to the velocity of the sea.
Both the simulating and real data results confirm that the secondary positioning of shot point and receiver is feasible.
引文
[1]王辉,刘天放.炮点位置偏离对叠加的影响及其校正方法.煤田地质与勘探,2001,29(5):49~52
[2]陶格涛.地震观测系统中炮点位置校正方法研究:[硕士学位论文].北京:中国地质大学,2006
[3]冯凯,陈刚,罗敏学.二次定位技术的应用.石油地球物理勘探,2006,41(3):346~349
[4]杨正华,常军.海底电缆地震中二次定位法的探讨.石油物探,2002,41(3):330~333
[5]曾湘轶,杨文艳.浅析海底电缆地震采集作业二次定位系统.石油地球物理勘探,2001,36(2):220~226
[6]姜瑞林.海底电缆水下声波二次定位成果质量分析.石油仪器,1996,5(10):23~25
[7]杨怀春,刘怀山.声波二次定位技术在KD-1高精度地震采集中的应用.海洋地质动态,2004,20(4):33~36
[8]刘怀山,王兆国,童思友.基准网平差初至波定位方法及应用.海洋地质与第四纪地质,2004,24(4):135~139
[9]韩立强,常稳.海底电缆初至波二次定位技术的应用.石油物探,2003,42(4):501~512
[10] Fred J Barr. Dual-sensor OBC technology. The Leading Edge,1997,16(1):45~51
[11] Noel Zinn. Modeling velocity gradients in an OBC first-break positioning algorithm. EAGE Geneva,1997,May:26~30
[12]姜瑞林.海底电缆地震采集系统—初至波二次定位成果的质量评价.石油地球物理勘探,1999,34(6):670~674
[13]吴学兵,刘志田,宁靖.海洋石油勘探水听器二次定位新方法研究.中国石油大学学报,2006,30(5):23~26
[14]王成礼,宋玉龙,付强等.检波器二次剩余定位方法与效果.石油物探,2007,46(5):505~508
[15]宋玉龙.滩浅海地区地震勘探存在问题及解决方法.石油物探,2005,44(4):343~347
[16]彭永超,王洪杰,何雪梅.震源定位技术的应用与发展.物探装备,2006,16(增刊):11~13
[17]张振宇.折射波法检波器二次定位.西南石油学院学报,2005,27(2):21~24
[18]倪成洲,全海燕,陈刚,牛宏轩.一种高精度初至波二次定位新方法—搜索法.石油地球物理勘探,2008,43(2):131~157
[19]何樵登等.地震勘探—原理和方法.北京:地质出版社,1980:13~16
[20]陆基孟.地震勘探原理.东营:石油大学出版社,1993:123~150
[21]马在田.地震成像技术:有限差分法偏移.北京:石油工业出版社,1989:48~60
[22] Francesca Martini,Christopher J.Bean.Interface scattering versus body scattering in subbasalt imaging and application of prestack wave equation datuming. GEOPHYSICS, 2002, 67(5):1593~1601
[23] J.W.Wiggins.Kirchhoff integral extrapolation and migration of nonplanar data.GEOPHYSICS, 1984:49(8):1239~1248
[24] Bertrand Duquet,Kurt J.Marfurt, Joe A.Dellinger.Kirchhoff modeling inversion for reflectivity and subsurface illumination. GEOPHYSICS, 2000,65(4):1195~1209
[25] Zhenyue Liu, Norman Bleistein.Migration velocity analysis: Theory and an iterative algorithm. GEOPHYSICS,1995,60(1):142~153
[26] A.J.Berkhout,C.P.A.Wapenaar.One-way versions of the Kirchhoff integral. GEOPHYSICS, 1989, 54(4):460~467
[27] John R. Berryhill. Submarine canyons:Velocity replacement by wave-equation datuming before stace. GEOPHYSICS, 1986, 51(8):1572~1579
[28] A.J.别尔克豪特著,马在田,张叔伦译.地震偏移波场外推法声波成像.北京:石油工业出版社,1983:56~121
[29]渥·伊尔马滋著,刘怀山等译.地震资料分析.北京:石油工业出版社,2006:359~497
[30]刘喜武,刘洪.波动方程地震偏移成像方法的现状与进展.地球物理学进展,2002,17(4):582~591
[31]陈生昌,马在田,WU RU-Shan.波动方程角度域偏移成像.计算物理,2007,24(2):211~216
[32]王喜双,张颖.地震叠前时间偏移处理技术.石油勘探与开发,2006,33(4):416~419
[33] Samuel H.Gray等著.地震偏移问题及其解决方案.勘探地球物理进展,2002,25(2):44~60
[34]崔汝国,覃天,凌勋等.叠前时间偏移成像技术及其应用.物探与化探,2006,30(6):541~544
[35]王贺林.叠前时间偏移技术在关家堡地区地震资料处理中的应用.石油地球物理勘探,2006,41(增刊):1~6
[36]马昭军,唐建明.叠前时间偏移在三维转换波资料处理中的应用.石油物探,2007,46(2):174~180
[37]吴庆举,李永华,张瑞青等.接收函数的克希霍夫2D偏移方法.地球物理学报,2007,50(2):539~545
[38]陈伟,方伍宝.偏移成像技术.勘探地球物理进展,2003,26(5):451~462
[39]王洁,马永生,张铁强.偏移技术概述.中国西部油气地质,2007,3(1):79~84
[40]杨俊,贺振华,黄德济.速度模型对地震波场偏移成像的影响.物探化探计算技术,2006,28(2):113~116
[41]杨锴,许世勇,王华忠等.有限差分法波场延拓海水层基准面校正.中国海上油气(地质),1999,13(5):342~345
[42] P.B.Dillon. Vertical seismic profile migration using the kirchhoff integral. GEOPHYSICS, 1988, 53(6):786~799
[43] John R. Berryhill. Wave-equation datuming before stack. GEOPHYSICS, 1984, 49(11):2064~2066
[44] Jiangguo Sun. On the limited aperture migration in two dimensions. GEOPHYSICS, 1998, 63(3):984~994
[45] Zhou Yu, George A. McMechan, Phil D.Anno. Wavelet transform-based prestack multiscale Kirchhoff migration. GEOPHYSICS, 2004, 69(6):1505~1512
[46] HUANG Wwen-hua, LU chuan. A Mini Max Theorem for the Functionals with Hemicontinuous Gateaux Derivative and the Solution of the Boundary Value Problem for the Nonlinear Wave Equation. Chin.Quart. J. of Math, 2007,22(3):451~458
[47]周竹生,刘喜亮,熊孝雨.弹性介质中瑞雷面波有限差分法正演模拟.地球物理学报,2007,50(2):567~573
[48]王一博,杨惠珠.方位各向异性介质的多尺度有限差分法波场模拟.清华大学学报:自然科学版,2006,46(2):293~296
[49]冯英杰,杨长春,吴萍.地震波有限差分模拟综述.地球物理学进展,2007,22(2):487~491
[50]褚春雷,王修田.非规则三角网格有限差分法地震正演模拟.中国海洋大学学报,2005,35(1):43~48
[2]陶格涛.地震观测系统中炮点位置校正方法研究:[硕士学位论文].北京:中国地质大学,2006
[3]冯凯,陈刚,罗敏学.二次定位技术的应用.石油地球物理勘探,2006,41(3):346~349
[4]杨正华,常军.海底电缆地震中二次定位法的探讨.石油物探,2002,41(3):330~333
[5]曾湘轶,杨文艳.浅析海底电缆地震采集作业二次定位系统.石油地球物理勘探,2001,36(2):220~226
[6]姜瑞林.海底电缆水下声波二次定位成果质量分析.石油仪器,1996,5(10):23~25
[7]杨怀春,刘怀山.声波二次定位技术在KD-1高精度地震采集中的应用.海洋地质动态,2004,20(4):33~36
[8]刘怀山,王兆国,童思友.基准网平差初至波定位方法及应用.海洋地质与第四纪地质,2004,24(4):135~139
[9]韩立强,常稳.海底电缆初至波二次定位技术的应用.石油物探,2003,42(4):501~512
[10] Fred J Barr. Dual-sensor OBC technology. The Leading Edge,1997,16(1):45~51
[11] Noel Zinn. Modeling velocity gradients in an OBC first-break positioning algorithm. EAGE Geneva,1997,May:26~30
[12]姜瑞林.海底电缆地震采集系统—初至波二次定位成果的质量评价.石油地球物理勘探,1999,34(6):670~674
[13]吴学兵,刘志田,宁靖.海洋石油勘探水听器二次定位新方法研究.中国石油大学学报,2006,30(5):23~26
[14]王成礼,宋玉龙,付强等.检波器二次剩余定位方法与效果.石油物探,2007,46(5):505~508
[15]宋玉龙.滩浅海地区地震勘探存在问题及解决方法.石油物探,2005,44(4):343~347
[16]彭永超,王洪杰,何雪梅.震源定位技术的应用与发展.物探装备,2006,16(增刊):11~13
[17]张振宇.折射波法检波器二次定位.西南石油学院学报,2005,27(2):21~24
[18]倪成洲,全海燕,陈刚,牛宏轩.一种高精度初至波二次定位新方法—搜索法.石油地球物理勘探,2008,43(2):131~157
[19]何樵登等.地震勘探—原理和方法.北京:地质出版社,1980:13~16
[20]陆基孟.地震勘探原理.东营:石油大学出版社,1993:123~150
[21]马在田.地震成像技术:有限差分法偏移.北京:石油工业出版社,1989:48~60
[22] Francesca Martini,Christopher J.Bean.Interface scattering versus body scattering in subbasalt imaging and application of prestack wave equation datuming. GEOPHYSICS, 2002, 67(5):1593~1601
[23] J.W.Wiggins.Kirchhoff integral extrapolation and migration of nonplanar data.GEOPHYSICS, 1984:49(8):1239~1248
[24] Bertrand Duquet,Kurt J.Marfurt, Joe A.Dellinger.Kirchhoff modeling inversion for reflectivity and subsurface illumination. GEOPHYSICS, 2000,65(4):1195~1209
[25] Zhenyue Liu, Norman Bleistein.Migration velocity analysis: Theory and an iterative algorithm. GEOPHYSICS,1995,60(1):142~153
[26] A.J.Berkhout,C.P.A.Wapenaar.One-way versions of the Kirchhoff integral. GEOPHYSICS, 1989, 54(4):460~467
[27] John R. Berryhill. Submarine canyons:Velocity replacement by wave-equation datuming before stace. GEOPHYSICS, 1986, 51(8):1572~1579
[28] A.J.别尔克豪特著,马在田,张叔伦译.地震偏移波场外推法声波成像.北京:石油工业出版社,1983:56~121
[29]渥·伊尔马滋著,刘怀山等译.地震资料分析.北京:石油工业出版社,2006:359~497
[30]刘喜武,刘洪.波动方程地震偏移成像方法的现状与进展.地球物理学进展,2002,17(4):582~591
[31]陈生昌,马在田,WU RU-Shan.波动方程角度域偏移成像.计算物理,2007,24(2):211~216
[32]王喜双,张颖.地震叠前时间偏移处理技术.石油勘探与开发,2006,33(4):416~419
[33] Samuel H.Gray等著.地震偏移问题及其解决方案.勘探地球物理进展,2002,25(2):44~60
[34]崔汝国,覃天,凌勋等.叠前时间偏移成像技术及其应用.物探与化探,2006,30(6):541~544
[35]王贺林.叠前时间偏移技术在关家堡地区地震资料处理中的应用.石油地球物理勘探,2006,41(增刊):1~6
[36]马昭军,唐建明.叠前时间偏移在三维转换波资料处理中的应用.石油物探,2007,46(2):174~180
[37]吴庆举,李永华,张瑞青等.接收函数的克希霍夫2D偏移方法.地球物理学报,2007,50(2):539~545
[38]陈伟,方伍宝.偏移成像技术.勘探地球物理进展,2003,26(5):451~462
[39]王洁,马永生,张铁强.偏移技术概述.中国西部油气地质,2007,3(1):79~84
[40]杨俊,贺振华,黄德济.速度模型对地震波场偏移成像的影响.物探化探计算技术,2006,28(2):113~116
[41]杨锴,许世勇,王华忠等.有限差分法波场延拓海水层基准面校正.中国海上油气(地质),1999,13(5):342~345
[42] P.B.Dillon. Vertical seismic profile migration using the kirchhoff integral. GEOPHYSICS, 1988, 53(6):786~799
[43] John R. Berryhill. Wave-equation datuming before stack. GEOPHYSICS, 1984, 49(11):2064~2066
[44] Jiangguo Sun. On the limited aperture migration in two dimensions. GEOPHYSICS, 1998, 63(3):984~994
[45] Zhou Yu, George A. McMechan, Phil D.Anno. Wavelet transform-based prestack multiscale Kirchhoff migration. GEOPHYSICS, 2004, 69(6):1505~1512
[46] HUANG Wwen-hua, LU chuan. A Mini Max Theorem for the Functionals with Hemicontinuous Gateaux Derivative and the Solution of the Boundary Value Problem for the Nonlinear Wave Equation. Chin.Quart. J. of Math, 2007,22(3):451~458
[47]周竹生,刘喜亮,熊孝雨.弹性介质中瑞雷面波有限差分法正演模拟.地球物理学报,2007,50(2):567~573
[48]王一博,杨惠珠.方位各向异性介质的多尺度有限差分法波场模拟.清华大学学报:自然科学版,2006,46(2):293~296
[49]冯英杰,杨长春,吴萍.地震波有限差分模拟综述.地球物理学进展,2007,22(2):487~491
[50]褚春雷,王修田.非规则三角网格有限差分法地震正演模拟.中国海洋大学学报,2005,35(1):43~48