大回线源瞬变电磁一维自适应反演方法及应用
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摘要
提出了一种适用于大回线源瞬变电磁法框内任意测点垂直Z分量的一维反演方法。该算法采用CMD正则化因子优化方案、光滑度函数和自然边界条件对反演过程进行了约束,减小了初值的依赖度,保证了反演过程的自主性和反演结果的稳定性;在反演过程中,在保证模型残差沿梯度下降的同时,对模型修正量的最大值进行了限制,使反演模型不易陷入局部极小,保证了反演结果全局的收敛性;同时反演的灵敏度矩阵采用牛顿法进行更新,减少了整个反演计算的工作量。最后通过五层的双低阻层模型、双高阻层模型和实测资料证明了该算法可靠。
A one-dimensional inversion method for the vertical Z component of any measuring point in the frame of the large loop source transient electromagnetic method is proposed in this paper. The algorithm uses the CMD regularization factor optimization scheme,smoothness function and natural boundary conditions to constrain the inversion process,reduce the initial value dependence,and ensure the autonomy of the inversion process and the stability of the inversion results. In the inversion process,while ensuring that the model residual decreases along the gradient,the maximum value of the model correction is limited,so that the inversion model is not easy to fall into the local minimum,which ensures the global convergence of the inversion results. The sensitivity matrix is updated by Newton's method,thus reducing the workload of the entire inversion calculation. Finally,the reliability of the algorithm is guaranteed by five-layer double low-resistance layer model,double high-resistance layer model and measured data.
A one-dimensional inversion method for the vertical Z component of any measuring point in the frame of the large loop source transient electromagnetic method is proposed in this paper. The algorithm uses the CMD regularization factor optimization scheme,smoothness function and natural boundary conditions to constrain the inversion process,reduce the initial value dependence,and ensure the autonomy of the inversion process and the stability of the inversion results. In the inversion process,while ensuring that the model residual decreases along the gradient,the maximum value of the model correction is limited,so that the inversion model is not easy to fall into the local minimum,which ensures the global convergence of the inversion results. The sensitivity matrix is updated by Newton's method,thus reducing the workload of the entire inversion calculation. Finally,the reliability of the algorithm is guaranteed by five-layer double low-resistance layer model,double high-resistance layer model and measured data.
引文
[1]薛国强,于景邨.瞬变电磁法在煤炭领域的研究与应用新进展[J].地球物理学进展,2017,32(1):319-326.Xue G Q,Yu J C.New development of TEM research and application in coal mine exploration[J].Progress in Geophysics,2017,32(1):0319-0326.
[2]程建远,石显新.中国煤炭物探技术的现状与发展[J].地球物理学进展,2013,28(4):2024-2032.Chen J Y,Shi X X. Current status and development of coal geophysical technology in China[J]. Progress in Geophys,2013,28(4):2024-2032.
[3]陈卫营,薛国强.瞬变电磁法多装置探测技术在煤矿采空区调查中的应用[J].地球物理学进展,2013,28(5):2709-2717.Chen W Y,Xue G Q. Application on coal-mine voids detection with multi-device TEM technology[J]. Progress in Geophys,2013,28(5):2709-2717.
[4]赵越,李貅,王祎鹏.大回线源瞬变电磁全域视电阻率定义[J].地球物理学进展,2015,30(4):1856-1863.Zhao Y,Li X,Wang Y P. Full-domain apparent resistivity definition for large-loop TEM[J]. Progress in Geophys,2015,30(4):1856-1863.
[5]薛国强,李貅,底青云.瞬变电磁法正反演问题研究进展[J].地球物理学进展,2008,23(4):1165-1172.Xue G Q,Li X,Di Q Y. Research progress in TEM forward modeling and inversion calculation[J]. Progress in Geophys,2008,23(4):1165-1172.
[6]刘晓.瞬变电磁法三维正演及非线性共轭梯度反演研究[D].北京:中国地质大学(北京),2016.Li X. Study of Three-dimensional TEM Forward Modeling and Non-linear Conjugate Gradients Inversion[D]. Beijing:China University of Geosciences(Beijing),2016.
[7]戴锐,张达,冀虎.大定源瞬变电磁法反演效果分析[J].有色金属:矿山部分,2017,69(3):1-4.Dai R,Zhang D,Ji H. Analysis of Large loop transient electromagnetic method inversion effect[J]. Nonferrous Metals:Mining Section,2017,69(3):1-4.
[8]张维.大定源瞬变电磁法一维正反演研究[D].长沙:中南大学,2013.Zhang W.The Study about 1D Forward and Inversion of large loop TEM[D]. Changsha:Central South University,2013.
[9]徐玉聪,赵宁,秦策,等.大定源瞬变电磁一维自适应正则化反演[J].地质与勘探,2015,51(2):360-365.Xu Y C,Zhao N,Qin C,et al. One-dimensional adaptive regularization inversion of transient electromagnetic sounding with a large fixed source[J]. Geology and Exploration,2015,51(2):360-365.
[10]翁爱华.Occam反演及其在瞬变电磁测深申的应用[J].地质与勘探,2007,43(5):74-76.Weng A H. OCCAM's inversion and its application to transient electromagnetic method[J]. Geology and Prospecting,2007,43(5):74-76.
[11]周道卿,谭捍东,王卫平.频率域航空电磁资料Occam反演研究[J].物探与化探,2006,30(2):71-74.Zhou D Q,Tan H D,Wang W P. The OCCAM inversion in faem data processing[J]. Geophysical and Geochemical Exploration,2006,30(2):71-74.
[12]李明星,肖林通,张倚瑞,等.瞬变电磁粒子群优化反演研究[J].煤炭技术,2014,33(9):302-304.Li M X,Xiao L T,Zhang Y R,et al. Research on particle swarm optimization inversion of transient electromagnetic method[J].Coal Technology,2014,33(9):302-304.
[13] Constable S C,Parker R L,Constable C G. Occam's inversion:A practical algorithm for generating smooth model from electromagnetic sounding data[J]. Geophysics,1987,52(2):289.
[14]毛立峰,王绪本,陈斌.直升机航空瞬变电磁自适应正则化一维反演方法研究[J].地球物理学进展,2011,26(1):300-305.Mao L F,Wang X B,Chen B.Study on an adaptive regularized 1D inversion method of helicopter TEM data[J].Progress in geophys.,2011,26(1):300-305.
[15]陈小斌,赵国泽,汤吉,等.大地电磁自适应正则化反演算法[J].地球物理学报,2005,48(4):937-946.Chen X B,Zhao G Z,Tang J,et al.An adaptive regularized inversion algorithm for magnetotelluric data. Chinese J. Geophys.,2005,48(4):937-946.
[16]李刚,潘和平,王智,等.回线源瞬变电磁法一维反演算法[J].煤田地质与勘探,2017,45(5):161-166.Li G,Pan H P,Wang Z,et al. One-dimensional inversion for loop source transient electromagnetic method[J]. Coal Geology&Exploration,2017,45(5):161-166.
[2]程建远,石显新.中国煤炭物探技术的现状与发展[J].地球物理学进展,2013,28(4):2024-2032.Chen J Y,Shi X X. Current status and development of coal geophysical technology in China[J]. Progress in Geophys,2013,28(4):2024-2032.
[3]陈卫营,薛国强.瞬变电磁法多装置探测技术在煤矿采空区调查中的应用[J].地球物理学进展,2013,28(5):2709-2717.Chen W Y,Xue G Q. Application on coal-mine voids detection with multi-device TEM technology[J]. Progress in Geophys,2013,28(5):2709-2717.
[4]赵越,李貅,王祎鹏.大回线源瞬变电磁全域视电阻率定义[J].地球物理学进展,2015,30(4):1856-1863.Zhao Y,Li X,Wang Y P. Full-domain apparent resistivity definition for large-loop TEM[J]. Progress in Geophys,2015,30(4):1856-1863.
[5]薛国强,李貅,底青云.瞬变电磁法正反演问题研究进展[J].地球物理学进展,2008,23(4):1165-1172.Xue G Q,Li X,Di Q Y. Research progress in TEM forward modeling and inversion calculation[J]. Progress in Geophys,2008,23(4):1165-1172.
[6]刘晓.瞬变电磁法三维正演及非线性共轭梯度反演研究[D].北京:中国地质大学(北京),2016.Li X. Study of Three-dimensional TEM Forward Modeling and Non-linear Conjugate Gradients Inversion[D]. Beijing:China University of Geosciences(Beijing),2016.
[7]戴锐,张达,冀虎.大定源瞬变电磁法反演效果分析[J].有色金属:矿山部分,2017,69(3):1-4.Dai R,Zhang D,Ji H. Analysis of Large loop transient electromagnetic method inversion effect[J]. Nonferrous Metals:Mining Section,2017,69(3):1-4.
[8]张维.大定源瞬变电磁法一维正反演研究[D].长沙:中南大学,2013.Zhang W.The Study about 1D Forward and Inversion of large loop TEM[D]. Changsha:Central South University,2013.
[9]徐玉聪,赵宁,秦策,等.大定源瞬变电磁一维自适应正则化反演[J].地质与勘探,2015,51(2):360-365.Xu Y C,Zhao N,Qin C,et al. One-dimensional adaptive regularization inversion of transient electromagnetic sounding with a large fixed source[J]. Geology and Exploration,2015,51(2):360-365.
[10]翁爱华.Occam反演及其在瞬变电磁测深申的应用[J].地质与勘探,2007,43(5):74-76.Weng A H. OCCAM's inversion and its application to transient electromagnetic method[J]. Geology and Prospecting,2007,43(5):74-76.
[11]周道卿,谭捍东,王卫平.频率域航空电磁资料Occam反演研究[J].物探与化探,2006,30(2):71-74.Zhou D Q,Tan H D,Wang W P. The OCCAM inversion in faem data processing[J]. Geophysical and Geochemical Exploration,2006,30(2):71-74.
[12]李明星,肖林通,张倚瑞,等.瞬变电磁粒子群优化反演研究[J].煤炭技术,2014,33(9):302-304.Li M X,Xiao L T,Zhang Y R,et al. Research on particle swarm optimization inversion of transient electromagnetic method[J].Coal Technology,2014,33(9):302-304.
[13] Constable S C,Parker R L,Constable C G. Occam's inversion:A practical algorithm for generating smooth model from electromagnetic sounding data[J]. Geophysics,1987,52(2):289.
[14]毛立峰,王绪本,陈斌.直升机航空瞬变电磁自适应正则化一维反演方法研究[J].地球物理学进展,2011,26(1):300-305.Mao L F,Wang X B,Chen B.Study on an adaptive regularized 1D inversion method of helicopter TEM data[J].Progress in geophys.,2011,26(1):300-305.
[15]陈小斌,赵国泽,汤吉,等.大地电磁自适应正则化反演算法[J].地球物理学报,2005,48(4):937-946.Chen X B,Zhao G Z,Tang J,et al.An adaptive regularized inversion algorithm for magnetotelluric data. Chinese J. Geophys.,2005,48(4):937-946.
[16]李刚,潘和平,王智,等.回线源瞬变电磁法一维反演算法[J].煤田地质与勘探,2017,45(5):161-166.Li G,Pan H P,Wang Z,et al. One-dimensional inversion for loop source transient electromagnetic method[J]. Coal Geology&Exploration,2017,45(5):161-166.