三维激发极化法反演研究及其在金属矿勘探中的应用
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摘要
激发极化法在金属矿、硫化矿等资源勘探方面应用较广.随着勘探设备与计算机硬件的发展,所采集到的数据具有观测数据量大、布极方式多样等特点.针对实测数据的特点,我们研究完成了基于并行技术的激发极化法对数反演算法,该算法具有如下特点:(1)通过压缩存储技术和并行技术的集成实现了可以处理大数据特征的反演算法;(2)利用对数反演来约束每次计算得到新模型的电导率恒为正,充电率在0到1之间变化,从而保证反演的稳定性和可靠性.本文首先设计了两组对比模型进行试验,通过对不同区块数据采用不同加权的方式来减弱噪声对反演结果影响的效果;其次,采用并行技术提高了反演的计算速度,并利用理论模型分析了不同电极装置对反演分辨率的影响.最后,在甘肃某金属矿开发前景区利用激发极化法开展了中梯装置的采集工作,利用加权后的观测数据反演推断出了测区金属矿开发靶区的大致位置及分布特征.
The induced polarization tomography has been extensively used in mineral exploration,investigation of sulfide ore,and other resources detection.With the development of exploration instruments and computer hardware,the amount of observed data in field surveys is getting larger and electrode array is more diverse.Based on the characteristics of observed data,we develop an inversion strategy for the induced polarization data that integrates the parallel technology and log-barrier method.The inversion strategy has the following characteristics:(1)The inversion strategy can handle large amounts of observed data with the compression storage and parallel technology;(2)Using the log-conductivity and log-barrier methods constrain the inverse model more reasonable that the resistivity is guaranteed to be positive and the chargeability always varies between 0 and 1.We firstly conduct two groups of comparative experiments with synthetic models.The experiments aim at controlling the effects of the noise in inversion result with giving the different weighting coefficients to the datum acquired in different areas that simulate the actual situation in the field.Second,the parallel technology is adopted to improve the inversion calculation speed.Meanwhile,we study the effects of the type of electrode array on the inversion resolution with synthetic models.Last,we employed the induced polarization tomography with the central gradient array in a potential area of mineral exploration in Gansu province,the inverted maps from the inversion with different weighting coefficients shows that the approximate location and subsurface three-dimensional resistivity and chargeability distribution of the mineral developing target in the survey area are delineated.
The induced polarization tomography has been extensively used in mineral exploration,investigation of sulfide ore,and other resources detection.With the development of exploration instruments and computer hardware,the amount of observed data in field surveys is getting larger and electrode array is more diverse.Based on the characteristics of observed data,we develop an inversion strategy for the induced polarization data that integrates the parallel technology and log-barrier method.The inversion strategy has the following characteristics:(1)The inversion strategy can handle large amounts of observed data with the compression storage and parallel technology;(2)Using the log-conductivity and log-barrier methods constrain the inverse model more reasonable that the resistivity is guaranteed to be positive and the chargeability always varies between 0 and 1.We firstly conduct two groups of comparative experiments with synthetic models.The experiments aim at controlling the effects of the noise in inversion result with giving the different weighting coefficients to the datum acquired in different areas that simulate the actual situation in the field.Second,the parallel technology is adopted to improve the inversion calculation speed.Meanwhile,we study the effects of the type of electrode array on the inversion resolution with synthetic models.Last,we employed the induced polarization tomography with the central gradient array in a potential area of mineral exploration in Gansu province,the inverted maps from the inversion with different weighting coefficients shows that the approximate location and subsurface three-dimensional resistivity and chargeability distribution of the mineral developing target in the survey area are delineated.
引文
Beard L P,Hohmann G W,Tripp A C.1996.Fast resistivity/IPinversion using a low-contrast approximation.Geophysics,61(1):169-179,doi:10.1190/1.1443937．
Constable S C,Parker R L,Constable C G.1987.Occam′s inversion:A practical algorithm for generating smooth models from electromagnetic sounding data.Geophysics,52(3):289-300,doi:10.1190/1.1442303．
Dai W J.2010.Metallogenic study of Huaniushan Au-Ag-Pb-Zn Deposit,Beishan area,Gansu province.Geology and Mineral Resources of South China(in Chinese),2010(3):25-33,doi:10.3969/j.issn.1007-3701.2010.03.004．
Dey A,Morrison H F.1979.Resistivity modeling for arbitrarily shaped three-dimensional structures.Geophysics,44(4):753-780,doi:10.1190/1.1440975．
Dong H P,Wang Y.2017.The research on graphite ore deposit by using induced polarization method in Xinhure,Wulatezhongqi.Chinese Journal of Engineering Geophysics(in Chinese),14(4):421-426,doi:10.3969/j.issn.1672-7940.2017.04.007．
Gill P,Murray W,Ponceleon D,et al.1991.Solving reduced KKTsystems in barrier methods for linear and quadratic programming.Technical Report SOL,91(7):1-26．
Golub G H,Heath M,Wahba G.1979.Generalized cross-validation as a method for choosing agood ridge parameter.Technometrics,21(2):215-223,doi:10.2307/1268518．
Iwashita T,Shimasaki M.2002.Algebraic multicolor ordering for parallelized ICCG solver in finite-element analyses.IEEETransactions on Magnetics,38(2):429-432,doi:10.1109/20.996114．
Iwashita T,Shimasaki M,Lu J W.2005.Parallel ICCG solvers for a finite-element eddy-current analysis on heterogeneous parallel computation environment．∥IEEE/ACES International Conference on Wireless Communications and Applied Computational Electromagnetics,2005.Honolulu,HI,USA:IEEE．
Jiao F Q,Zhao X S,Chen C.2013.The application of the metallic factor to the interpretation of IP anomalies.Geophysical and Geochemical Exploration(in Chinese),37(5):848-852,doi:10.11720/j.issn.1000-8918.2013.5.17．
La Brecque D J.1991.IP tomography．∥61st Ann.Internat Mtg.,Soc.Expi.Geophys..Expanded Abstracts,413-416．
Li Y G,Oldenburg D W.2000.3Dinversion of induced polarization data.Geophysics,65(6):1931-1945,doi:10.1190/1.1444877．
Li Z X,Tan H D,Fu S S,et al.2015.Two-dimensional synchronous inversion of TDIP with cross-gradient constraint.Chinese Journal of Geophysics(in Chinese),58(12):4718-4726,doi:10.6038/cjg20151232．
Lin F L,Wang G J,Yang X Y.2016.Application of comprehensive electromagnetic study in deep mineralization mechanism-A case study of the Wuxi polymetallic ore deposit,south Anhui.ChineseJournalof Geophysics(in Chinese),59(11):4323-4337,doi:10.6038/cjg20161132．
Loke M H,Wilkinson P B,Chambers J E.2010.Parallel computation of optimized arrays for 2-D electrical imaging surveys.Geophysical Journal International,183(3):1302-1315,doi:10.1111/j.1365-246X.2010.04796.x．
Meijerink J A,Van Der Vorst H A.1977.An iterative solution method for linear systems of which the coefficient matrix is a symmetric M-matrix.Mathematics of Computation,31(137):148．
Oldenburg D W,Li Y G.1994.Inversion of induced polarization data.Geophysics,59(9):1327-1341,doi:10.1190/1.1443692．
Pan Y B,Chen Y Y,Wang J W.2017.Application of IP intermediate gradient method in vein type gold mine of desert.World Nonferrous Metal(in Chinese),4(17):107-110．
Pelton W H,Rijo L,Swift C M.1978.Inversion of two-dimensional resistivity and induced-polarization data.Geophysics,43(4):788-803,doi:10.1190/1.1440854．
Poole E L,Ortega J M.1987.Multicolor ICCG methods for vector computers.SIAM Journal on Numerical Analysis,24(6):1394-1418,doi:10.1137/0724090．
Sasaki Y.1982.Automatic interpretation of induced polarization data over two-dimensional structures.Memoirs of the Faculty of Engineering,Kyushu University,42(1):59-74．
Sastry S P,Shontz S M,Vavasis S A.2011.A log-barrier method for mesh quality improvement．∥Proceedings of the 20th International Meshing Roundtable.Berlin:Springer,329-346．
Sastry S P,Shontz S M,Vavasis S A.2014.A log-barrier method for mesh quality improvement and untangling.Engineering with Computers,30(3):315-329,doi:10.1007/s00366-012-0294-6．
Schwarzbach C,B9rner R U,Spitzer K.2005.Two-dimensional inversion of direct current resistivity data using aparallel,multiobjective genetic algorithm.Geophysical Journal International,162(3):685-695,doi:10.1111/j.1365-246X.2005.02702.x．
Seigel H O.1959.Mathematical formulation and type curves for induced polarization.Geophysics,24(3):547-565,doi:10.1190/1.1438625．
Sun R B,Chu L X,Zhao Y J,et al.2017.Application of the time domain induced polarization method to a Zn-W polymetallic deposit in Xianghuang Banner,Inner Mongolia.Geology and Exploration(in Chinese),53(3):519-527．
Wright S J.2001.On the convergence of the Newton/log-barrier method.Mathematical Programming,90(1):71-100,doi:10.1007/PL00011421．
Wu X P,Xu G M,Li S C.1998.The calculation of three-dimensional geoelectric field of point source by incomplete cholesky conjugate gradient method.Chinese Journal of Geophysics(Acta Geophysica Sinica)(in Chinese),41(6):848-855．
Wu X P,Xu G M.2000.Study on 3-D resistivity inversion using conjugate gradient method.Chinese Journal of Geophysics(in Chinese),43(3):420-427．
Yang J G,Zhai J Y,Yang H W,et al.2010.Metallotectonics and prospection of the huaniushan exhalogene Gold-Silver-Lead-Zinc deposit in Beishan,Gansu Province.Geotectonica et Metallogenia(in Chinese),34(2):246-254,doi:10.3969/j.issn.1001-1552.2010.02.011．
Ye Y X,Li Y G,Deng J Z,et al.2014.2.5Dinduced polarization forward modeling using the adaptive finite-element method.Applied Geophysics,11(4):500-507,doi:10.1007/s11770-014-0455-z．
Zhang X D,Fang J,Zhang D Y,et al.2017.The application of the induced polarization method to the replacement resources exploration of the Dongxi gold deposit.Geophysical and Geochemical Exploration(in Chinese),41(3):445-451,doi:10.11720/wtyht.2017.3.08．
Zhao H Y.2017.Application of high-power induced polarization to exploration of graphite ore in Zhangjiakou.Chinese Journal of Engineering Geophysics(in Chinese),14(5):546-551,doi:10.3969/j.issn.1672-7940.2017.05.007．
Zhou D,Chen A X,Dong Z M,et al.2016.Application of the induced polarization method in exploration of a skarnized copper polymetallic deposit in Benxi,Liaoning province.Geology and Exploration(in Chinese),52(4):688-694．
Zhou H X,Peng Q Y,Jiang Y L.2013.Applying the transient electromagnetic methods and the induced polarization method to searching for lead-zinc deposits.Computing Techniques for Geophysical and Geochemical Exploration(in Chinese),35(6):664-667,doi:10.3969/j.issn.1001-1749.2013.06.06．
Zou G H,Liang H Q,Yin H D.2013.Application frame using
compressed diagonal storage format in iterative methods.Computing Techniques for Geophysical and Geochemical Exploration(in Chinese),35(1):107-111,doi:10.3969/j.issn.1001-1749.2013.01.17．
代文军．2010．甘肃北山花牛山金银铅锌矿床成因探讨．华南地质与矿产，2010(3):25-33,doi:10.3969/j.issn.1007-3701.2010.03.004．
董和平，王勇．2017．乌拉特中旗新忽热石墨矿的激发极化法研究．工程地球物理学报，14(4):421-426,doi:10.3969/j.issn.1672-7940.2017.04.007．
焦方谦，赵新生，陈川．2013．激电异常解释中金属因素的应用．物探与化探，37(5):848-852,doi:10.11720/j.issn.1000-8918.2013.5.17．
李兆祥，谭捍东，付少帅等．2015．基于交叉梯度约束的时间域激发极化法二维同步反演．地球物理学报，58(12):4718-4726,doi:10.6038/cjg20151232．
林方丽，王光杰，杨晓勇．2016．综合电磁法在矿区深部成矿机制中的应用研究---以皖南乌溪多金属矿区为例．地球物理学报，59(11):4323-4337,doi:10.6038/cjg20161132．
潘燕兵，陈媛媛，王君伟．2017．激电中梯测量在沙漠地区脉型金矿勘查中的应用．世界有色金属，（17):107-110．
孙仁斌，楚丽霞，赵绎钧等．2017．时间域激发极化法在内蒙古镶黄旗某锌钨多金属矿的应用．地质与勘探，53(3):519-527．
吴小平，徐果明，李时灿．1998．利用不完全Cholesky共轭梯度法求解点源三维地电场．地球物理学报，41(6):848-855．
吴小平，徐果明．2000．利用共轭梯度法的电阻率三维反演研究．地球物理学报，43(3):420-427．
杨建国，翟金元，杨宏武等．2010．甘肃花牛山喷流沉积型金银铅锌矿床控矿因素与找矿前景分析．大地构造与成矿学，34(2):246-254,doi:10.3969/j.issn.1001-1552.2010.02.011．
张晓东，方捷，张定源等．2017．激发极化法在东溪金矿接替资源勘查中的应用．物探与化探，41(3):445-451,doi:10.11720/wtyht.2017.3.08．
赵后越．2017．大功率激电在张家口地区石墨矿勘查中的应用．工程地球物理学报，14(5):546-551,doi:10.3969/j.issn.1672-7940.2017.05.007．
周多，陈安霞，董再民等．2016．激发极化法在辽宁本溪某矽卡岩型铜多金属矿勘查中的应用．地质与勘探，52(4):688-694．
周洪祥，彭乾云，江玉乐．2013．瞬变电磁法与直流激发极化法在寻找铅锌矿中的应用．物探化探计算技术，35(6):664-667,doi:10.3969/j.issn.1001-1749.2013.06.06．
邹桂红，梁华庆，尹洪东．2013．迭代法中压缩对角存储的应用框架．物探化探计算技术，35(1):107-111,doi:10.3969/j.issn.1001-1749.2013.01.17.
Constable S C,Parker R L,Constable C G.1987.Occam′s inversion:A practical algorithm for generating smooth models from electromagnetic sounding data.Geophysics,52(3):289-300,doi:10.1190/1.1442303．
Dai W J.2010.Metallogenic study of Huaniushan Au-Ag-Pb-Zn Deposit,Beishan area,Gansu province.Geology and Mineral Resources of South China(in Chinese),2010(3):25-33,doi:10.3969/j.issn.1007-3701.2010.03.004．
Dey A,Morrison H F.1979.Resistivity modeling for arbitrarily shaped three-dimensional structures.Geophysics,44(4):753-780,doi:10.1190/1.1440975．
Dong H P,Wang Y.2017.The research on graphite ore deposit by using induced polarization method in Xinhure,Wulatezhongqi.Chinese Journal of Engineering Geophysics(in Chinese),14(4):421-426,doi:10.3969/j.issn.1672-7940.2017.04.007．
Gill P,Murray W,Ponceleon D,et al.1991.Solving reduced KKTsystems in barrier methods for linear and quadratic programming.Technical Report SOL,91(7):1-26．
Golub G H,Heath M,Wahba G.1979.Generalized cross-validation as a method for choosing agood ridge parameter.Technometrics,21(2):215-223,doi:10.2307/1268518．
Iwashita T,Shimasaki M.2002.Algebraic multicolor ordering for parallelized ICCG solver in finite-element analyses.IEEETransactions on Magnetics,38(2):429-432,doi:10.1109/20.996114．
Iwashita T,Shimasaki M,Lu J W.2005.Parallel ICCG solvers for a finite-element eddy-current analysis on heterogeneous parallel computation environment．∥IEEE/ACES International Conference on Wireless Communications and Applied Computational Electromagnetics,2005.Honolulu,HI,USA:IEEE．
Jiao F Q,Zhao X S,Chen C.2013.The application of the metallic factor to the interpretation of IP anomalies.Geophysical and Geochemical Exploration(in Chinese),37(5):848-852,doi:10.11720/j.issn.1000-8918.2013.5.17．
La Brecque D J.1991.IP tomography．∥61st Ann.Internat Mtg.,Soc.Expi.Geophys..Expanded Abstracts,413-416．
Li Y G,Oldenburg D W.2000.3Dinversion of induced polarization data.Geophysics,65(6):1931-1945,doi:10.1190/1.1444877．
Li Z X,Tan H D,Fu S S,et al.2015.Two-dimensional synchronous inversion of TDIP with cross-gradient constraint.Chinese Journal of Geophysics(in Chinese),58(12):4718-4726,doi:10.6038/cjg20151232．
Lin F L,Wang G J,Yang X Y.2016.Application of comprehensive electromagnetic study in deep mineralization mechanism-A case study of the Wuxi polymetallic ore deposit,south Anhui.ChineseJournalof Geophysics(in Chinese),59(11):4323-4337,doi:10.6038/cjg20161132．
Loke M H,Wilkinson P B,Chambers J E.2010.Parallel computation of optimized arrays for 2-D electrical imaging surveys.Geophysical Journal International,183(3):1302-1315,doi:10.1111/j.1365-246X.2010.04796.x．
Meijerink J A,Van Der Vorst H A.1977.An iterative solution method for linear systems of which the coefficient matrix is a symmetric M-matrix.Mathematics of Computation,31(137):148．
Oldenburg D W,Li Y G.1994.Inversion of induced polarization data.Geophysics,59(9):1327-1341,doi:10.1190/1.1443692．
Pan Y B,Chen Y Y,Wang J W.2017.Application of IP intermediate gradient method in vein type gold mine of desert.World Nonferrous Metal(in Chinese),4(17):107-110．
Pelton W H,Rijo L,Swift C M.1978.Inversion of two-dimensional resistivity and induced-polarization data.Geophysics,43(4):788-803,doi:10.1190/1.1440854．
Poole E L,Ortega J M.1987.Multicolor ICCG methods for vector computers.SIAM Journal on Numerical Analysis,24(6):1394-1418,doi:10.1137/0724090．
Sasaki Y.1982.Automatic interpretation of induced polarization data over two-dimensional structures.Memoirs of the Faculty of Engineering,Kyushu University,42(1):59-74．
Sastry S P,Shontz S M,Vavasis S A.2011.A log-barrier method for mesh quality improvement．∥Proceedings of the 20th International Meshing Roundtable.Berlin:Springer,329-346．
Sastry S P,Shontz S M,Vavasis S A.2014.A log-barrier method for mesh quality improvement and untangling.Engineering with Computers,30(3):315-329,doi:10.1007/s00366-012-0294-6．
Schwarzbach C,B9rner R U,Spitzer K.2005.Two-dimensional inversion of direct current resistivity data using aparallel,multiobjective genetic algorithm.Geophysical Journal International,162(3):685-695,doi:10.1111/j.1365-246X.2005.02702.x．
Seigel H O.1959.Mathematical formulation and type curves for induced polarization.Geophysics,24(3):547-565,doi:10.1190/1.1438625．
Sun R B,Chu L X,Zhao Y J,et al.2017.Application of the time domain induced polarization method to a Zn-W polymetallic deposit in Xianghuang Banner,Inner Mongolia.Geology and Exploration(in Chinese),53(3):519-527．
Wright S J.2001.On the convergence of the Newton/log-barrier method.Mathematical Programming,90(1):71-100,doi:10.1007/PL00011421．
Wu X P,Xu G M,Li S C.1998.The calculation of three-dimensional geoelectric field of point source by incomplete cholesky conjugate gradient method.Chinese Journal of Geophysics(Acta Geophysica Sinica)(in Chinese),41(6):848-855．
Wu X P,Xu G M.2000.Study on 3-D resistivity inversion using conjugate gradient method.Chinese Journal of Geophysics(in Chinese),43(3):420-427．
Yang J G,Zhai J Y,Yang H W,et al.2010.Metallotectonics and prospection of the huaniushan exhalogene Gold-Silver-Lead-Zinc deposit in Beishan,Gansu Province.Geotectonica et Metallogenia(in Chinese),34(2):246-254,doi:10.3969/j.issn.1001-1552.2010.02.011．
Ye Y X,Li Y G,Deng J Z,et al.2014.2.5Dinduced polarization forward modeling using the adaptive finite-element method.Applied Geophysics,11(4):500-507,doi:10.1007/s11770-014-0455-z．
Zhang X D,Fang J,Zhang D Y,et al.2017.The application of the induced polarization method to the replacement resources exploration of the Dongxi gold deposit.Geophysical and Geochemical Exploration(in Chinese),41(3):445-451,doi:10.11720/wtyht.2017.3.08．
Zhao H Y.2017.Application of high-power induced polarization to exploration of graphite ore in Zhangjiakou.Chinese Journal of Engineering Geophysics(in Chinese),14(5):546-551,doi:10.3969/j.issn.1672-7940.2017.05.007．
Zhou D,Chen A X,Dong Z M,et al.2016.Application of the induced polarization method in exploration of a skarnized copper polymetallic deposit in Benxi,Liaoning province.Geology and Exploration(in Chinese),52(4):688-694．
Zhou H X,Peng Q Y,Jiang Y L.2013.Applying the transient electromagnetic methods and the induced polarization method to searching for lead-zinc deposits.Computing Techniques for Geophysical and Geochemical Exploration(in Chinese),35(6):664-667,doi:10.3969/j.issn.1001-1749.2013.06.06．
Zou G H,Liang H Q,Yin H D.2013.Application frame using
compressed diagonal storage format in iterative methods.Computing Techniques for Geophysical and Geochemical Exploration(in Chinese),35(1):107-111,doi:10.3969/j.issn.1001-1749.2013.01.17．
代文军．2010．甘肃北山花牛山金银铅锌矿床成因探讨．华南地质与矿产，2010(3):25-33,doi:10.3969/j.issn.1007-3701.2010.03.004．
董和平，王勇．2017．乌拉特中旗新忽热石墨矿的激发极化法研究．工程地球物理学报，14(4):421-426,doi:10.3969/j.issn.1672-7940.2017.04.007．
焦方谦，赵新生，陈川．2013．激电异常解释中金属因素的应用．物探与化探，37(5):848-852,doi:10.11720/j.issn.1000-8918.2013.5.17．
李兆祥，谭捍东，付少帅等．2015．基于交叉梯度约束的时间域激发极化法二维同步反演．地球物理学报，58(12):4718-4726,doi:10.6038/cjg20151232．
林方丽，王光杰，杨晓勇．2016．综合电磁法在矿区深部成矿机制中的应用研究---以皖南乌溪多金属矿区为例．地球物理学报，59(11):4323-4337,doi:10.6038/cjg20161132．
潘燕兵，陈媛媛，王君伟．2017．激电中梯测量在沙漠地区脉型金矿勘查中的应用．世界有色金属，（17):107-110．
孙仁斌，楚丽霞，赵绎钧等．2017．时间域激发极化法在内蒙古镶黄旗某锌钨多金属矿的应用．地质与勘探，53(3):519-527．
吴小平，徐果明，李时灿．1998．利用不完全Cholesky共轭梯度法求解点源三维地电场．地球物理学报，41(6):848-855．
吴小平，徐果明．2000．利用共轭梯度法的电阻率三维反演研究．地球物理学报，43(3):420-427．
杨建国，翟金元，杨宏武等．2010．甘肃花牛山喷流沉积型金银铅锌矿床控矿因素与找矿前景分析．大地构造与成矿学，34(2):246-254,doi:10.3969/j.issn.1001-1552.2010.02.011．
张晓东，方捷，张定源等．2017．激发极化法在东溪金矿接替资源勘查中的应用．物探与化探，41(3):445-451,doi:10.11720/wtyht.2017.3.08．
赵后越．2017．大功率激电在张家口地区石墨矿勘查中的应用．工程地球物理学报，14(5):546-551,doi:10.3969/j.issn.1672-7940.2017.05.007．
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