定源TEM数据随偏移距变化特征模拟研究
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摘要
利用在频率域中表达式只有一重贝塞尔函数的偶极子及其剖分模式,将回线源剖分成多个偶极子的矢量叠加,通过数字滤波法实现对其求解,求得频率域电磁场,再由余弦变换将频率域电磁场转化到时间域,实现定源瞬变电磁法大偏移距一维正演计算.对测点在回线源内部所采集二次场随不同偏移距的变化特征,以及在不同地电模型条件下的变化特征进行了模拟研究,发现与中心点相比二次场的变化主要集中在早期,即随着介质电阻率的降低、回线源的增大和偏移距的增大,变化就越大.采用带约束的正则化反演方法,同时对反演电阻率值采用可行的上下限约束方法,可以消除此变化特征,还原地层电性变化规律,提高处理精度.
Use in frequency domain and its expression profile dipole only a Bessel function model, vector superposition will loop source is divided into several dipoles, realize the solution through the digital filter method, the frequency domain electromagnetic field, and then by the cosine transform in frequency domain electromagnetic field transformed into time domain to realize source transient electromagnetic large offset one-dimensional forward calculation. On the two field with different offset variation from measuring points in the internal loop, as well as in different geological conditions under the variation of geoelectric model was simulated and compared with the center point of the two field changes mainly in the early, namely with the increase of reduction, loop medium resistivity and offset distance increases, the greater the change. A regularized inversion method with constraints is applied. Meanwhile, a feasible upper and lower bound method is applied to retrieve the resistivity values, which can eliminate the variation characteristics, reduce the electrical change rule of the formation, and improve the processing accuracy.
Use in frequency domain and its expression profile dipole only a Bessel function model, vector superposition will loop source is divided into several dipoles, realize the solution through the digital filter method, the frequency domain electromagnetic field, and then by the cosine transform in frequency domain electromagnetic field transformed into time domain to realize source transient electromagnetic large offset one-dimensional forward calculation. On the two field with different offset variation from measuring points in the internal loop, as well as in different geological conditions under the variation of geoelectric model was simulated and compared with the center point of the two field changes mainly in the early, namely with the increase of reduction, loop medium resistivity and offset distance increases, the greater the change. A regularized inversion method with constraints is applied. Meanwhile, a feasible upper and lower bound method is applied to retrieve the resistivity values, which can eliminate the variation characteristics, reduce the electrical change rule of the formation, and improve the processing accuracy.
引文
Constable S C, Parker R L, Constable C G. 1987. Occam’s inversion: a practical algorithm for generating smooth models from electromagnetic sounding data [J]. Geophysics, 52(3): 289-300.
Feng B, Meng X H, Zhang B. 2010. Transmitting coil boundary effect for TEM large loop source and Elimination method [J]. Coal Geology &Exploration (in Chinese), 38(5): 61- 66.
Gao Y. 2014. A Study about 1D Forward and Inversion Algorithm of Rectangular Loop TEM [Master’s thesis]. Chengdu: Chengdu University of Technology.
GROOT-HEDLIN de C, CONSTABLE S. 1990. Occam’s inversion to generate smooth, two-dimensional models from magnetotelluric data [J]. Geophysics, 55(12): 1613-1624.
Guptasama D, Singh B. 1997. New digital linear filters for Hankel J0 and J1 transforms [J]. Geophysical Prospecting, 45(5): 745-762.
Han Z Q, Liu T, Ou Y J, et al. 2015. Application of large rectangular loop source TEM all-time apparent resistivity on colliery goaf exploration [J]. Progress in Geophysics (in Chinese), 30(1): 0343- 0349, doi: 10.6038/pg20150l50.
Han Z Q, Luo J, Liu T, et al. 2015. The application of fixed source loop transient electromagnetic method in the coal mine rich water area survey [J]. Progress in Geophysics (in Chinese), 30(4): 1705-1711, doi: 10.6038/pg20150425.
Li J H, Zhu Z Q, Zeng S H, et al. 2012. Progress of forward computation in transient electromagnetic method [J]. Progress in Geophysics (in Chinese), 27(4): 1393-1400, doi: 10.6038/j.issn.1004-2903.2012.04.013.
Li X. 2002. Theory and Application of Transient Electromagnetic [M]. Xi’an: Shaanxi Science and Technology Press.
Liu Y. 2009. The advantages and disadvantages comparison among TEM different loops [J]. Equipment for Geophysical Prospecting (in Chinese), 19(5): 325-327, 345.
Niu Z L. 2007. Principle of Electromagnetic Method in Time Domain [M]. Changsha: Central South University Press.
Qi Z P, Li X, Zhu H W, et al. 2011. Definition of apparent resistivity for non-center vertical component of Large-loop TEM configuration [J]. Progress in Geophys (in Chinese), 26(4): 1350-1358, doi: 10.3969/j.issn. 1004-2903. 2011.04.028.
Shi X X. 2005. Research on shielding of low-resistivity layer in Prospecting by transient electromagnetic method [Ph.D. thesis]. Beijing: China Coal Researeh Institute.
Xue G Q, Li X, Di Q Y. 2008. Research progress in TEM forward modeling and inversion calculation [J]. Progress in Geophysics (in Chinese), 23(4): 1165-1172.
Xue G Q, Li X, Di Q Y. 2008. Research progress in TEM forward modeling and inversion calculation [J]. Progress in Geophysics, 23(4): 1165-1172.
Yan S, Xue G Q, Chen M S. 2011. Review and perspective of theoretical study on large loop TEM response [J]. Progress in Geophysics (in Chinese), 26(3): 941-947, doi: 10.3969/j.issn.1004-2903.2011.03.020.
Zhang W, Wang X B, Qin Q Y. 2010. Research and application on numerical integration of Hankel transforms by digital filtering [J]. Geophysical and Geochemical Exploration (in Chinese), 34(6): 753-755.
冯兵, 孟小红, 张斌. 2010. TEM框内回线装置发射框边界影响及消除方法[J]. 煤田地质与勘探, 38(5): 61- 66.
高阳. 2014. 瞬变电磁法矩形框发射源一维正反演研究[硕士论文]. 成都: 成都理工大学.
韩自强, 刘涛, 欧阳进, 等. 2015. 矩形大定源回线TEM法全区视电阻率在煤田采空区勘探中的应用[J]. 地球物理学进展, 30(l): 0343- 0349, doi: 10.6038/pg20150150.
韩自强, 罗姣, 刘涛, 等. 2015. 定源回线瞬变电磁法在煤矿富水区调查中的应用[J]. 地球物理学进展, 30(4): 1705-1711, doi: 10.6038/pg20150425.
李建慧, 朱自强, 曾思红, 等. 2012. 瞬变电磁法正演计算进展[J]. 地球物理学进展, 27(4): 1393-1400, doi: 10.6038/j.issn.1004-2903.2012.04.013.
李貅. 2002. 瞬变电磁测深的理论与应用[M]. 西安: 陕西科学技术出版社.
刘英. 2009. 浅析瞬变电磁法不同回线装置的优缺点[J]. 物探装备, 19(5): 325-327, 345.
牛之琏. 2007. 时间域电磁法原理[M]. 长沙: 中南大学出版社.
戚志鹏, 李貅, 朱宏伟, 等. 2011. 大定源装置下瞬变电磁法视电阻率定义[J]. 地球物理学进展, 26(4): 1350-1358, doi: 10.3969/j.issn.1004-2903.2011.04.028.
石显新. 2005. 瞬变电磁法勘探中的低阻层屏蔽层问题研究[博士论文]. 北京: 煤炭科学研究总院.
薛国强, 李貅, 底青云. 2008. 瞬变电磁法正反演问题研究进展[J]. 地球物理学进展, 23(4): 1165-1172.
闫述, 薛国强, 陈明生. 2011. 大回线源瞬变电磁响应理论研究回顾及展望[J]. 地球物理学进展, 26(3): 941-947, doi: 10.3969/j.issn.1004-2903.2011.03.020.
张伟, 王绪本, 覃庆炎. 2010. 汉克尔变换的数值计算与精度的对比[J]. 物探与化探, 34(6): 753-755.
Feng B, Meng X H, Zhang B. 2010. Transmitting coil boundary effect for TEM large loop source and Elimination method [J]. Coal Geology &Exploration (in Chinese), 38(5): 61- 66.
Gao Y. 2014. A Study about 1D Forward and Inversion Algorithm of Rectangular Loop TEM [Master’s thesis]. Chengdu: Chengdu University of Technology.
GROOT-HEDLIN de C, CONSTABLE S. 1990. Occam’s inversion to generate smooth, two-dimensional models from magnetotelluric data [J]. Geophysics, 55(12): 1613-1624.
Guptasama D, Singh B. 1997. New digital linear filters for Hankel J0 and J1 transforms [J]. Geophysical Prospecting, 45(5): 745-762.
Han Z Q, Liu T, Ou Y J, et al. 2015. Application of large rectangular loop source TEM all-time apparent resistivity on colliery goaf exploration [J]. Progress in Geophysics (in Chinese), 30(1): 0343- 0349, doi: 10.6038/pg20150l50.
Han Z Q, Luo J, Liu T, et al. 2015. The application of fixed source loop transient electromagnetic method in the coal mine rich water area survey [J]. Progress in Geophysics (in Chinese), 30(4): 1705-1711, doi: 10.6038/pg20150425.
Li J H, Zhu Z Q, Zeng S H, et al. 2012. Progress of forward computation in transient electromagnetic method [J]. Progress in Geophysics (in Chinese), 27(4): 1393-1400, doi: 10.6038/j.issn.1004-2903.2012.04.013.
Li X. 2002. Theory and Application of Transient Electromagnetic [M]. Xi’an: Shaanxi Science and Technology Press.
Liu Y. 2009. The advantages and disadvantages comparison among TEM different loops [J]. Equipment for Geophysical Prospecting (in Chinese), 19(5): 325-327, 345.
Niu Z L. 2007. Principle of Electromagnetic Method in Time Domain [M]. Changsha: Central South University Press.
Qi Z P, Li X, Zhu H W, et al. 2011. Definition of apparent resistivity for non-center vertical component of Large-loop TEM configuration [J]. Progress in Geophys (in Chinese), 26(4): 1350-1358, doi: 10.3969/j.issn. 1004-2903. 2011.04.028.
Shi X X. 2005. Research on shielding of low-resistivity layer in Prospecting by transient electromagnetic method [Ph.D. thesis]. Beijing: China Coal Researeh Institute.
Xue G Q, Li X, Di Q Y. 2008. Research progress in TEM forward modeling and inversion calculation [J]. Progress in Geophysics (in Chinese), 23(4): 1165-1172.
Xue G Q, Li X, Di Q Y. 2008. Research progress in TEM forward modeling and inversion calculation [J]. Progress in Geophysics, 23(4): 1165-1172.
Yan S, Xue G Q, Chen M S. 2011. Review and perspective of theoretical study on large loop TEM response [J]. Progress in Geophysics (in Chinese), 26(3): 941-947, doi: 10.3969/j.issn.1004-2903.2011.03.020.
Zhang W, Wang X B, Qin Q Y. 2010. Research and application on numerical integration of Hankel transforms by digital filtering [J]. Geophysical and Geochemical Exploration (in Chinese), 34(6): 753-755.
冯兵, 孟小红, 张斌. 2010. TEM框内回线装置发射框边界影响及消除方法[J]. 煤田地质与勘探, 38(5): 61- 66.
高阳. 2014. 瞬变电磁法矩形框发射源一维正反演研究[硕士论文]. 成都: 成都理工大学.
韩自强, 刘涛, 欧阳进, 等. 2015. 矩形大定源回线TEM法全区视电阻率在煤田采空区勘探中的应用[J]. 地球物理学进展, 30(l): 0343- 0349, doi: 10.6038/pg20150150.
韩自强, 罗姣, 刘涛, 等. 2015. 定源回线瞬变电磁法在煤矿富水区调查中的应用[J]. 地球物理学进展, 30(4): 1705-1711, doi: 10.6038/pg20150425.
李建慧, 朱自强, 曾思红, 等. 2012. 瞬变电磁法正演计算进展[J]. 地球物理学进展, 27(4): 1393-1400, doi: 10.6038/j.issn.1004-2903.2012.04.013.
李貅. 2002. 瞬变电磁测深的理论与应用[M]. 西安: 陕西科学技术出版社.
刘英. 2009. 浅析瞬变电磁法不同回线装置的优缺点[J]. 物探装备, 19(5): 325-327, 345.
牛之琏. 2007. 时间域电磁法原理[M]. 长沙: 中南大学出版社.
戚志鹏, 李貅, 朱宏伟, 等. 2011. 大定源装置下瞬变电磁法视电阻率定义[J]. 地球物理学进展, 26(4): 1350-1358, doi: 10.3969/j.issn.1004-2903.2011.04.028.
石显新. 2005. 瞬变电磁法勘探中的低阻层屏蔽层问题研究[博士论文]. 北京: 煤炭科学研究总院.
薛国强, 李貅, 底青云. 2008. 瞬变电磁法正反演问题研究进展[J]. 地球物理学进展, 23(4): 1165-1172.
闫述, 薛国强, 陈明生. 2011. 大回线源瞬变电磁响应理论研究回顾及展望[J]. 地球物理学进展, 26(3): 941-947, doi: 10.3969/j.issn.1004-2903.2011.03.020.
张伟, 王绪本, 覃庆炎. 2010. 汉克尔变换的数值计算与精度的对比[J]. 物探与化探, 34(6): 753-755.