估计辐射参数的井间电磁波层析成像技术
|
摘要
为了避免使用不合理初始辐射场强和方向性因子带来的误差,研究了估计辐射参数的井间电磁波层析成像技术.通过时域有限差分法模拟表明,天线长度与波长的比值、钻孔充填情况、钻孔周围介质的物性均会影响偶极天线的初始辐射场强或方向性因子;为此结合已知的分层资料,将它们设为未知参数,并设定初始辐射场强与发射点位置相关,方向性因子随射线角度而变化;采用正则化反演方法,由钻孔资料建立了模型方差目标函数,使得反演结果与钻遇的地质特征保持一致.通过理论模型试验和实例应用分析表明,相对于传统射线层析成像方法,估计辐射参数的正则化层析成像技术有助于提高反演的准确性.
We present a ray-based amplitude tomography with radiation parameters estimation for cross-well radio-frequency electromagnetic data,which permits to avoid distortions from utilizing incorrect source strength and radiation pattern.Numerical simulations using the finite difference time domain method indicate that the source strength and radiation pattern are seriously affected by the ratio of antenna length to wavelength,the filling of borehole and properties of the surrounding materials.To solve these problems,combining with the existing stratified data,the source strength and radiation pattern are treated as unknown parameters with the assumption that the source strength varies with the position of the transmitter and radiation pattern changes with the ray angle.The regularization inversion method is adopted,and constraints are applied to the model according to the geological features of the boreholes revealed to make inversion results in accordance with geological characteristics from drilling.Tests on theoretical models and field data show that this regularized tomography technique with radiation parameters estimation can help improve the accuracy of inversion compared with traditional ray-based tomography.
We present a ray-based amplitude tomography with radiation parameters estimation for cross-well radio-frequency electromagnetic data,which permits to avoid distortions from utilizing incorrect source strength and radiation pattern.Numerical simulations using the finite difference time domain method indicate that the source strength and radiation pattern are seriously affected by the ratio of antenna length to wavelength,the filling of borehole and properties of the surrounding materials.To solve these problems,combining with the existing stratified data,the source strength and radiation pattern are treated as unknown parameters with the assumption that the source strength varies with the position of the transmitter and radiation pattern changes with the ray angle.The regularization inversion method is adopted,and constraints are applied to the model according to the geological features of the boreholes revealed to make inversion results in accordance with geological characteristics from drilling.Tests on theoretical models and field data show that this regularized tomography technique with radiation parameters estimation can help improve the accuracy of inversion compared with traditional ray-based tomography.
引文
Cao J X.2001.Conductivity tomography using dual frequency EMdata.Chinese Journal of Geophysics(in Chinese),44(z1):199-205．
Cao J X,He Z H,Zhu J S,et al.2003.Conductivity tomography at two frequencies.Geophysics,68(2):516-522．
Day-Lewis F D,Harris J M,Gorelick S M.2002.Time-lapse inversion of crosswell radar data.Geophysics,67(6):1740-1752．
Dines K A,Lytle R J.1979.Computerized geophysical tomography.Proceedings of the IEEE,67(7):1065-1073．
Feng R,Ma K X,Guo H,et al.1997.Electromagnetic wave tomography-image consistency and groundwater detection.Acta Seismologica Sinica(in Chinese),19(5):524-534．
Holliger K,Bergmann T.2002.Numerical modeling of borehole georadar data.Geophysics,67(4):1249-1257．
Holliger K,Musil M,Maurer H R.2001.Ray-based amplitude tomography for crosshole georadar data:A numerical assessment.Journal of Applied Geophysics,47(3-4):285-298．
Korpisalo A,Heikkinen E.2015.Radiowave imaging research(RIM)for determining the electrical conductivity of the rock in borehole section OL-KR4-OL-KR10 at Olkiluoto,Finland.Exploration Geophysics,46(2):141-152．
Liu L B,Lane J W,Quan Y L.1998.Radar attenuation tomography using the centroid frequency downshift method.Journal of Applied Geophysics,40(1-3):105-116．
Liu L Z.1986.Evaluating the normal field intensity in noisy environments for underground electromagnetic waves exploration.Computing Techniques for Geophysical and Geochemical Exploration(in Chinese),8(3):237-244．
Liu L Z.1990.Reconstruction of the distribution of relative attenuations in subsurface media:a new tomographic technique.Acta Geophysica Sinica(in Chinese),33(1):97-105．
Quan Y L,Harris J M.1997.Seismic attenuation tomography using the frequency shift method.Geophysics,62(3):895-905．
Sun J G.2002.The normal field in borehole electromagnetic wave method based on the modern antenna theory.Acta Geoscientia Sinica(in Chinese),23(6):567-571．
Thomson S,Hinde S.1993.Bringing geophysics into the mine:radio attenuation imaging and mine geology.Exploration Geophysics,24(3-4):805-810．
Wang W J,Farmer C,Ockendon J,et al.2011.A dual-parameter regularization method for electrical conductivity imaging.Chinese Journal of Geophysics(in Chinese),54(8):2154-2159,doi:10.3969/j.issn.0001-5733.2011.08.023．
Wang W J,Pan K J,Cao J X,et al.2009.Electrical conductivity imaging using dual-frequency EM data based on Tikhonov regularization.Chinese Journal of Geophysics(in Chinese),52(3):750-757．
Wei M G,Liu R Z.1999.A Normalization method for field strength amplitude of electromagnetic waves between wells.Geology and Prospecting(in Chinese),35(3):38-40,61．
Wu Y R.1982.Borehole Electromagnetic Method(in Chinese).Beijing:Geological Publishing House．
Yao J,Fan X M,Wang B.2009.Numerical simulation of electromagnetic propagation logging by FDTD in 3-D cylindrical coordinates.Well Logging Technology(in Chinese),33(3):233-237．
Yu L,Chouteau M,Boerner D E,et al.1998.On the imaging of radiofrequency electromagnetic data for cross-borehole mineral exploration.Geophysical Journal International,135(2):523-541．
曹俊兴．2001．双频电磁波电导率层析成像反演．地球物理学报，44(z1):199-205．
冯锐，马奎祥，郭鸿等．1997．电磁波层析成像---图像的一致性及地下水探测．地震学报，19(5):524-534．
刘立振．1986．在噪声情况下计算电波正常场．物化探计算技术，8(3):237-244．
刘立振．1990．重建地下介质相对衰减的分布：新的成象方法．地球物理学报，33(1):97-105．
孙建国．2002．基于近代天线理论的钻孔电磁波法正常场．地球学报，23(6):567-571．
王文娟，Farmer C,Ockendon J等．2011．双参数混合正则化方法及在电导率反演成像中的应用．地球物理学报，54(8):2154-2159,doi:10.3969/j.issn.0001-5733.2011.08.023．
王文娟，潘克家，曹俊兴等．2009．基于Tikhonov正则化的双频电磁波电导率成像反演．地球物理学报，52(3):750-757．
魏明果，刘润泽．1999．井间电磁波场强幅值的相对归一化．地质与勘探，35(3):38-40,61．
吴以仁．1982．钻孔电磁波法．北京：地质出版社．
姚军，范晓敏，王斌．2009．三维圆柱坐标系下FDTD法对电磁波传播测井的数值模拟．测井技术，33(3):233-237.
Cao J X,He Z H,Zhu J S,et al.2003.Conductivity tomography at two frequencies.Geophysics,68(2):516-522．
Day-Lewis F D,Harris J M,Gorelick S M.2002.Time-lapse inversion of crosswell radar data.Geophysics,67(6):1740-1752．
Dines K A,Lytle R J.1979.Computerized geophysical tomography.Proceedings of the IEEE,67(7):1065-1073．
Feng R,Ma K X,Guo H,et al.1997.Electromagnetic wave tomography-image consistency and groundwater detection.Acta Seismologica Sinica(in Chinese),19(5):524-534．
Holliger K,Bergmann T.2002.Numerical modeling of borehole georadar data.Geophysics,67(4):1249-1257．
Holliger K,Musil M,Maurer H R.2001.Ray-based amplitude tomography for crosshole georadar data:A numerical assessment.Journal of Applied Geophysics,47(3-4):285-298．
Korpisalo A,Heikkinen E.2015.Radiowave imaging research(RIM)for determining the electrical conductivity of the rock in borehole section OL-KR4-OL-KR10 at Olkiluoto,Finland.Exploration Geophysics,46(2):141-152．
Liu L B,Lane J W,Quan Y L.1998.Radar attenuation tomography using the centroid frequency downshift method.Journal of Applied Geophysics,40(1-3):105-116．
Liu L Z.1986.Evaluating the normal field intensity in noisy environments for underground electromagnetic waves exploration.Computing Techniques for Geophysical and Geochemical Exploration(in Chinese),8(3):237-244．
Liu L Z.1990.Reconstruction of the distribution of relative attenuations in subsurface media:a new tomographic technique.Acta Geophysica Sinica(in Chinese),33(1):97-105．
Quan Y L,Harris J M.1997.Seismic attenuation tomography using the frequency shift method.Geophysics,62(3):895-905．
Sun J G.2002.The normal field in borehole electromagnetic wave method based on the modern antenna theory.Acta Geoscientia Sinica(in Chinese),23(6):567-571．
Thomson S,Hinde S.1993.Bringing geophysics into the mine:radio attenuation imaging and mine geology.Exploration Geophysics,24(3-4):805-810．
Wang W J,Farmer C,Ockendon J,et al.2011.A dual-parameter regularization method for electrical conductivity imaging.Chinese Journal of Geophysics(in Chinese),54(8):2154-2159,doi:10.3969/j.issn.0001-5733.2011.08.023．
Wang W J,Pan K J,Cao J X,et al.2009.Electrical conductivity imaging using dual-frequency EM data based on Tikhonov regularization.Chinese Journal of Geophysics(in Chinese),52(3):750-757．
Wei M G,Liu R Z.1999.A Normalization method for field strength amplitude of electromagnetic waves between wells.Geology and Prospecting(in Chinese),35(3):38-40,61．
Wu Y R.1982.Borehole Electromagnetic Method(in Chinese).Beijing:Geological Publishing House．
Yao J,Fan X M,Wang B.2009.Numerical simulation of electromagnetic propagation logging by FDTD in 3-D cylindrical coordinates.Well Logging Technology(in Chinese),33(3):233-237．
Yu L,Chouteau M,Boerner D E,et al.1998.On the imaging of radiofrequency electromagnetic data for cross-borehole mineral exploration.Geophysical Journal International,135(2):523-541．
曹俊兴．2001．双频电磁波电导率层析成像反演．地球物理学报，44(z1):199-205．
冯锐，马奎祥，郭鸿等．1997．电磁波层析成像---图像的一致性及地下水探测．地震学报，19(5):524-534．
刘立振．1986．在噪声情况下计算电波正常场．物化探计算技术，8(3):237-244．
刘立振．1990．重建地下介质相对衰减的分布：新的成象方法．地球物理学报，33(1):97-105．
孙建国．2002．基于近代天线理论的钻孔电磁波法正常场．地球学报，23(6):567-571．
王文娟，Farmer C,Ockendon J等．2011．双参数混合正则化方法及在电导率反演成像中的应用．地球物理学报，54(8):2154-2159,doi:10.3969/j.issn.0001-5733.2011.08.023．
王文娟，潘克家，曹俊兴等．2009．基于Tikhonov正则化的双频电磁波电导率成像反演．地球物理学报，52(3):750-757．
魏明果，刘润泽．1999．井间电磁波场强幅值的相对归一化．地质与勘探，35(3):38-40,61．
吴以仁．1982．钻孔电磁波法．北京：地质出版社．
姚军，范晓敏，王斌．2009．三维圆柱坐标系下FDTD法对电磁波传播测井的数值模拟．测井技术，33(3):233-237.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |