山峰对电性源地面瞬变电磁响应的影响及校正方法

doi:10.11720/wtyht.2023.1489

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摘要

在山区进行应用电性源瞬变电磁法勘探易受复杂地形影响,瞬变电磁响应会产生畸变,给数据解释造成困难。为此,基于三维非结构时间域有限元算法,开展了地形效应影响规律和校正方法的研究。首先,利用非结构四面体网格对山峰地形进行精细刻画,计算多种带地形模型响应,分析地形效应的影响规律;然后,基于电磁场线性叠加原理提出地形效应校正方法,根据实际高程数据建立山峰地电模型,通过三维正演计算出山峰模型响应,将山峰模型响应减去平坦大地模型响应得到地形响应,再从总响应中剔除地形响应,获得地形校正后的瞬变电磁响应。研究表明:山峰地形对瞬变电磁响应的影响主要集中在早期,随着时间推移,影响逐渐减弱;地形效应主要集中于山体附近,影响强度取决于测点距山顶的距离;影响范围与响应幅值与山体规模成正比;相对高阻山体的地形影响强度更大。通过设计多种带地形简单规则异常体模型进行仿真,发现经过校正的瞬变电磁响应与直接正演的响应吻合较好,在一定程度上能够有效消除地形效应。对地形效应影响和校正方法的研究,可为复杂地形地区瞬变电磁数据处理解释提供参考。

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	周钟航
	张莹莹

关键词 ：电性源瞬变电磁法, 山峰, 地形效应, 地形校正方法, 三维正演

Abstract：

The grounded-source transient electromagnetic (TEM) method, which enjoys the advantages of high topographic adaptability and large exploration depths, is suitable for deep resource exploration in mountainous areas. However, the TEM responses can be distorted due to topographic effects, causing great difficulties in data interpretation. This study investigated the influence patterns and correction method of topographic effects based on the three-dimensional unstructured time-domain finite element method. First, this study conducted the fine-scale description of mountains using unstructured tetrahedral grids, calculated the response of various topographic models, and analyzed the influence patterns of topographic effects. Then, it proposed a correction method for topographic effects based on the principle of the linear superposition principle of electromagnetic fields, established a geoelectric model of mountains according to the actual elevation data, and calculated the model responses through three-dimensional forward modeling. Subsequently, this study determined the topographic responses by subtracting the flat Earth model responses from the mountain model responses and then obtained the corrected TEM responses by removing the topographic responses from the total responses. The results are as follows: (1) The influence of mountains on the TEM responses is concentrated in the early stage and weakens gradually with time; (2) The topographic effects are concentrated near mountains, and their intensity depends on the distance of survey points from mountain peaks; (3) The influencing range and response amplitude of mountains are proportional to the mountain scale. In other words, a larger mountain scale corresponds to a larger influencing range and higher response amplitude; (4) Mountains with relatively high resistivity show more intense topographic influence. As shown by multiple models with simple and regular topographic anomalies, the corrected TEM responses, which match well with the responses from direct forward modeling, can effectively eliminate topographic effects to a certain extent. The research on the influence and correction method of topographic effects can be used as a reference for the processing and interpretation of TEM data of areas with complex terrain.

Key words： grounded-source transient electromagnetic method hill topographic effect terrain correction three-dimensional forward modeling

收稿日期: 2022-09-29 修回日期: 2022-10-30 出版日期: 2023-10-20

ZTFLH:

P631.3

基金资助:新疆维吾尔自治区天池博士计划项目

通讯作者: 张莹莹

作者简介: 周钟航(1998-),男,在读硕士,研究方向为瞬变电磁数值建模与应用。Email:zhou1229hang@163.com

引用本文:

周钟航, 张莹莹. 山峰对电性源地面瞬变电磁响应的影响及校正方法[J]. 物探与化探, 2023, 47(5): 1236-1249.
ZHOU Zhong-Hang, ZHANG Ying-Ying. Correction of the influence of mountains on grounded-source transient electromagnetic responses. Geophysical and Geochemical Exploration, 2023, 47(5): 1236-1249.

链接本文:

https://www.wutanyuhuatan.com/CN/10.11720/wtyht.2023.1489 或 https://www.wutanyuhuatan.com/CN/Y2023/V47/I5/1236

Fig.1 四面体单元棱边电场分布

Fig.2 山峰模型示意

Fig.3 1 000 m偏移距山峰模型瞬变电磁响应

Fig.4 3 000 m偏移距山峰模型瞬变电磁响应

Fig.5 山峰带异常体模型示意

Fig.6 山峰带异常体模型瞬变电磁响应

Fig.7 不同电阻率山峰带异常体模型示意

Fig.8 不同电阻率山峰模型瞬变电磁响应

Fig.9 山峰模型地形校正前后瞬变电磁响应

Fig.10 山峰模型瞬变电磁校正响应多测道曲线

Fig.11 不同规模山峰模型示意

Fig.12 不同规模山峰模型地形校正前后瞬变电磁响应

Fig.13 不同规模山峰模型瞬变电磁校正响应多测道曲线

Fig.14 山峰带球体异常模型地形校正前后瞬变电磁响应

Fig.15 山峰带球体异常模型地形校正前后瞬变电磁响应相对误差

Fig.16 山峰带球体异常模型瞬变电磁校正响应多测道曲线

Fig.17 不同电阻率山峰模型地形校正前后瞬变电磁响应

Fig.18 不同电阻率山峰模型地形校正前后瞬变电磁响应相对误差

Fig.19 不同电阻率山峰模型瞬变电磁校正响应多测道曲线

Fig.20 山峰带倾斜板状体模型示意

Fig.21 山峰带倾斜板状体模型地形校正前后瞬变电磁响应

Fig.22 山峰带倾斜板状体模型地形校正前后瞬变电磁响应相对误差

Fig.23 山峰带倾斜板状体模型瞬变电磁校正响应多测道曲线

[1]	Nabighian M N. Electromagnetic methods in applied geophysics:Volume 1,theory[M]. Society of Exploration Geophysicists, 1988.
[2]	薛国强, 宋建平, 武军杰, 等. 瞬变电磁法探测公路隧道工程中的不良地质构造[J]. 长安大学学报:地球科学版, 2003, 25(4):73-75.
[2]	Xue G Q, Song J P, Wu J J, et al. Application of TEM to detect the harmful geological structures in highway tunnel engineering[J]. Journal of Chang`an University:Earth Science Edition, 2003, 25(4):73-75.
[3]	张建智, 胡富杭, 刘海啸, 等. 煤矿老窑采空区地-井TEM响应特征[J]. 物探与化探, 2022, 46(1):191-197.
[3]	Zhang J Z, Hu F H, Liu H X, et al. TEM response characteristics of borehole in goaves of old coal mines[J]. Geophysical and Geochemical Exploration, 2022, 46(1):191-197.
[4]	于景邨, 刘志新, 刘树才, 等. 深部采场突水构造矿井瞬变电磁法探查理论及应用[J]. 煤炭学报, 2007, 32(8):818-821.
[4]	Yu J C, Liu Z X, Liu S C, et al. Theoretical analysis of mine transient electromagnetic method and its application in detecting water burst structures in deep coal stope[J]. Journal of China Coal Society, 2007, 32(8):818-821.
[5]	侯彦威, 徐亚飞. 低阻覆盖层下深部富水区的TEM探测效果[J]. 物探与化探, 2013, 37(4):715-719.
[5]	Hou Y W, Xu Y F. The effect of the transient electromagnetic method in detecting deep water-rich area under low resistivity layer[J]. Geophysical and Geochemical Exploration, 2013, 37(4):715-719.
[6]	柳建新, 赵然, 郭振威. 电磁法在金属矿勘查中的研究进展[J]. 地球物理学进展, 2019, 34(1):151-160.
[6]	Liu J X, Zhao R, Guo Z W. Research progress of electromagnetic methods in the exploration of metal deposits[J]. Progress in Geophysics, 2019, 34(1):151-160.
[7]	Hördt A, Andrieux P, Neubauer F M, et al. A first attempt at monitoring underground gas storage by means of time-lapse multichannel transient electromagnetics[J]. Geophysical Prospecting, 2000, 48:489-509. doi: 10.1046/j.1365-2478.2000.00192.x
[8]	李贺. 特殊探测环境下的瞬变电磁探测方法研究[D]. 西安: 长安大学, 2021.
[8]	Li H. Research on transient electromagnetic detection method under special detection environment[D]. Xi’an: Chang’an University, 2021.
[9]	Ku C C, Hsieh M S, Lim S H. The topographic effect in electromagnetic fields[J]. Canadian Journal of Earth Sciences, 1973, 10(5):645-656. doi: 10.1139/e73-065
[10]	Hördt A, Müeller M D. Understanding LOTEM data from mountainous terrain[J]. Geophysics, 2000, 65(4):1113-1123. doi: 10.1190/1.1444804
[11]	Yin C C, Qi Y F, Liu Y H, et al. 3D time-domain airborne EM forward modeling with topography[J]. Journal of Applied Geophysics, 2016, 134:11-22. doi: 10.1016/j.jappgeo.2016.08.002
[12]	Li J H, Lu X S, Farquharson C G, et al. A finite-element time-domain forward solver for electromagnetic methods with complex-shaped loop sources[J]. Geophysics, 2018, 83(3):E117-E132. doi: 10.1190/geo2017-0216.1
[13]	Jiracek G R. Near-surface and topographic distortions in electromagnetic induction[J]. Surveys in Geophysics, 1990, 11(2):163-203. doi: 10.1007/BF01901659
[14]	肖怀宇. 带地形的瞬变电磁法三维数值模拟[D]. 北京: 中国地质大学(北京), 2006.
[14]	Xiao H Y. Three-dimensional numerical modeling considering the topography of TEM[D]. Beijing: China University of geosciences(Beijing), 2006.
[15]	Tang X G, Hu W B, Yan L J. Topographic effects on long offset transient electromagnetic response[J]. Applied Geophysics, 2011, 8(4):277-284. doi: 10.1007/s11770-011-0297-x
[16]	邱卫忠. 回线源TEM山地勘探中的地形影响和校正方法[J]. 煤田地质与勘探, 2012, 40(5):78-81.
[16]	Qiu W Z. Topographic effects and correction methods of loop source TEM in mountainous exploration[J]. Coal Geology & Exploration, 2012, 40(5):78-81.
[17]	张博, 殷长春, 刘云鹤, 等. 起伏地表频域/时域航空电磁系统三维正演模拟研究[J]. 地球物理学报, 2016, 59(4):1506-1520.
[17]	Zhang B, Yin C C, Liu Y H, et al. 3D modeling on topographic effect for frequency/time-domain airborne EM systems[J]. Chinese Journal of Geophysics, 2016, 59(4):1506-1520.
[18]	陈明生. 对瞬变电磁测深几个问题的思考(五)——地形对TEM资料的影响[J]. 煤田地质与勘探, 2017, 45(6):139-142.
[18]	Chen M S. Reflections on several lssues of transient electromagnetie sounding (5):The influence of topography on TEM data[J]. Coal Geology & Exploration, 2017, 45(6):139-142.
[19]	赵越, 李貅, 王祎鹏, 等. 三维起伏地形条件下航空瞬变电磁响应特征研究[J]. 地球物理学报, 2017, 60(1):383-402.
[19]	Zhao Y, Li X, Wang Y P, et al. Characteristics of terrain effect of 3-D ATEM[J]. Chinese Journal of Geophysics, 2017, 60(1):383-402.
[20]	马炳镇. 起伏地形下地面瞬变电磁法三维正演数值模拟研究[J]. 物探与化探, 2018, 42(4):777-784.
[20]	Ma B Z. Three dimensional numerical simulation of transient electromagnetic method in undulating terrain[J]. Geophysical and Geochemical Exploration, 2018, 42(4):777-784.
[21]	齐彦福, 李貅, 孙乃泉, 等. 短偏移距电性源瞬变电磁地形影响特征分析[J]. 吉林大学学报:地球科学版, 2021, 52(1):247-260.
[21]	Qi Y F, Li X, Sun N Q, et al. Analysis of influence characteristics of topography on short-offset grounded-source transient electromagnetic responses[J]. Journal of Jilin University:Earth Science Edition, 2021, 52(1):247-260.
[22]	Sternberg B K, Washburne J C, Pellerin L. Correction for the static shift in magnetotellurics using transient electromagnetic soundings[J]. Geophysics, 1988, 53(11):1459-1468. doi: 10.1190/1.1442426
[23]	李金铭. 地电场与电法勘探[M]. 北京: 地质出版社, 2005.
[23]	Li J M. Geoelectric fields and electrical exploration[M]. Beijing: Geological Press, 2005.
[24]	严良俊, 王正茂, 谢兴兵. 表层结构调查中的TEM地形校正[J]. 勘探地球物理进展, 2007, 30(5):396-398.
[24]	Yan L J, Wang Z M, Xie X B. TEM terrain correction in surface structure surveys[J]. Progress in Exploration Geophysics, 2007, 30(5):396-398.
[25]	王信文, 冯宏, 高志宏, 等. TEM技术地形校正初探[C]// 陕西省地球物理文集, 2008:127-131.
[25]	Wang X W, Feng H, Gao Z H, et al. TEM technology terrain correction[C]// Geophysics Collection of Shanxi province, 2008:127-131.
[26]	范涛. 煤田电法勘探中的TEM地形校正方法[J]. 物探与化探, 2012, 36(2):246-249.
[26]	Fan T. TEM topographic correction in coal field electrical exploration[J]. Geophysical & Geochemical Exploration, 2012, 36(2):246-249.
[27]	薛国强, 闫述, 陈卫营. 电磁测深数据地形影响的快速校正[J]. 地球物理学报, 2016, 59(12):4408-4413.
[27]	Xue G Q, Yan S, Chen W Y. A fast topographic correction method for electromagnetic data[J]. Chinese Journal of Geophysics, 2016, 59(12):4408-4413.
[28]	Liu Y H, Yin C C, Qiu C K, et al. 3-D inversion of transient EM data with topography using unstructured tetrahedral grids[J]. Geophysical Journal International, 2019, 217(1):301-318. doi: 10.1093/gji/ggz014
[29]	齐彦福, 智庆全, 李貅, 等. 考虑关断时间的地面瞬变电磁三维带地形反演[J]. 地球物理学报, 2021, 64(7):2566-2577.
[29]	Qi Y F, Zhi Q Q, Li X, et al. Three-dimensional ground TEM inversion over a topographic earth considering ramp time[J]. Chinese Journal of Geophysics, 2021, 64(7):2566-2577.
[30]	Yin C C, Hodges G S. Influence of displacement currents on the response of helicopter electromagnetic systems[J]. Geophysics, 2005, 70(4):G95-G100. doi: 10.1190/1.1993710
[31]	齐彦福. 复杂介质中时间域航空电磁数据仿真技术研究[D]. 长春: 吉林大学, 2017.
[31]	Qi Y F. Time-domain airborne electromagnetic simulation for complex medium[D]. Changchun: Jilin University, 2017.
[32]	Zhdanov M S, Keller G V. The Geoelectrical Methods in Geophysical Exploration[M]. Amsterdam:Elsevier, 1994.
[33]	孙怀凤, 李貅, 卢绪山, 等. 隧道强干扰环境瞬变电磁响应规律与校正方法:以TBM为例[J]. 地球物理学报, 2016, 59(12):4720-4732.
[33]	Sun H F, Li X, Lu X S, et al. Transient electromagnetic responses in tunnels with strong interferences and the correcting method:A TBM example[J]. Chinese Journal of Geophysics, 2016, 59(12):4720-4732.

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