3-D AMT Array Exploration in the Selaha Fault and Adjacent Area
-
摘要:
为了能在川藏铁路色拉哈段隧道选址过程中最大限度地规避地质灾害体，本文针对色拉哈断裂及邻区开展了音频大地电磁三维阵列探测研究，获得了研究区可靠的三维精细电性结构.结合地表活动断裂调查结果，对区内三维电性分布特征进行了综合解释.研究表明，色拉哈断裂及邻区地表至500 m，整体表现为高阻特征，局部受断裂控制的区域为低阻特征；500 m以下电阻率下降显著，推测是断裂带在500 m以下的深部构造富含水体所致；此外，位于色拉哈断裂北侧的木格措南阶区以及南侧的断裂交汇区东侧发育两处高导体C1和C2，推测为区内含水的构造软岩，在设计隧道路线的过程中，应尽量避让.
Abstract:In order to avoid the geological hazards to the greatest extent in the processing of tunnel routes in the Selaha segment of the Sichuan-Tibet Railway line, we use audio magnetotelluric (AMT) data and obtain a reliable 3-D electrical structure model in the Salaha fault and adjacent area. The 3-D electrical resistivity model is comprehensively interpreted with the investigation of active faults. There is a large-scale high resistivity body at the depth from surface to 500 m, where the local area controlled by the faults is of low resistivity. Beneath the shallow 500 m, the resistivity decreases significantly, which results from the fault zone rich in aqueous fluids. In addition, there are two high conductors C1 and C2 in the study region; one is in the Mugecuo south stage area at the northwestern side of the Salaha fault, and the other is in the eastern side of the fault intersection area. These high conductors are presumed to be structural soft rocks. Therefore, it should be avoided as far as possible in designing the tunnel route.
-
Key words:
- Selaha fault /
- 3-D inversion with topography /
- electrical structure /
- seismogeology
-
图 1 研究区构造简图（a）及音频大地电磁测点分布图（b）
F1. 色拉哈断裂；F1-1、F1-2、F1-3、F1-4. 色拉哈分支断裂；F2. 木格措南断裂
Fig. 1. Schematic tectonic setting of the study area (a) and locations of the AMT sites (b)
图 2 测区地形模型（a）、三维电性结构模型（b）及不同深度的电阻率曲面模型（c）
Fig. 2. Topographic grid data (a), 3-D electrical structure (b) and resistivity surface models of different depth (c)
图 4 100、200、350、500、700、1 000、1 400和2 000 m的电阻率曲面模型
Fig. 4. Resistivity surface models of 100, 200, 350, 500, 700, 1 000, 1 400 and 2 000 m
图 5 色拉哈断裂不同区段的二维电性结构剖面
Fig. 5. Electrical structure profiles of the Selaha fault in the region
图 6 平地形与带地形反演电性结构对比
图a和c分别是500 m和700 m的电阻率切片；图b和d分别是500 m和700 m的电阻率曲面
Fig. 6. Electrical structure comparison between 3-D inversion without topography and 3-D inversion with topography
-
[1] Bai, M. K., Chevalier, M. L., Pan, J. W., et al., 2018. Southeastward Increase of the Late Quaternary Slip-Rate of the Xianshuihe Fault, Eastern Tibet. Geodynamic and Seismic Hazard Implications. Earth and Planetary Science Letters, 485: 19-31. https://doi.org/10.1016/j.epsl.2017.12.045 [2] Blake, S., Henry, T., Muller, M. R., et al., 2016. Understanding Hydrothermal Circulation Patterns at a Low-Enthalpy Thermal Spring Using Audio-Magnetotelluric Data: A Case Study from Ireland. Journal of Applied Geophysics, 132: 1-16. https://doi.org/10.1016/j.jappgeo.2016.06.007 [3] Cagniard, L., 1953. Basic Theory of the Magneto-Telluric Method of Geophysical Prospecting. Geophysics, 18(3): 605-635. https://doi.org/10.1190/1.1437915 [4] Chen, X. B., Zhao, G. Z., Zhan, Y., 2004. A Visual Integrated Windows System for MT Data Process and Interpreation. Oil Geophysical Prospecting, 39(Suppl. ): 11-16 (in Chinese with English abstract). [5] Egbert, G. D., 1997. Robust Multiple-Station Magnetotelluric Data Processing. Geophysical Journal International, 130(2): 475-496. https://doi.org/10.1111/j.1365-246X.1997.tb05663.x [6] Egbert, G. D., Kelbert, A., 2012. Computational Recipes for Electromagnetic Inverse Problems. Geophysical Journal International, 189(1): 251-267. https://doi.org/10.1111/j.1365-246X.2011.05347.x [7] Gamble, T. D., Goubau, W. M., Clarke, J., 1979. Magnetotellurics with a Remote Magnetic Reference. Geophysics, 44(1): 53-68. https://doi.org/10.1190/1.1440923 [8] Guo, C. B., Du, Y. B., Zhang, Y. S., et al., 2015. Geohazard Effects of the Xianshuihe Fault and Characteristics of Typical Landslides in Western Sichuan. Geological Bulletin of China, 34(1): 121-134 (in Chinese with English abstract). [9] Kelbert, A., Meqbel, N., Egbert, G. D., et al., 2014. ModEM: A Modular System for Inversion of Electromagnetic Geophysical Data. Computers & Geosciences, 66: 40-53. https://doi.org/10.1016/j.cageo.2014.01.010 [10] Li, H. B., Pan, J. W., Sun, Z. M., et al., 2021. Continental Tectonic Deformation and Seismic Activity: A Case Study from the Tibetan Plateau. Acta Geologica Sinica, 95(1): 194-213 (in Chinese with English abstract). [11] Li, P. B., Li, Z., Li, H., 2019. Application of High-Frequency Magnetotelluric Method to Railway Tunnel Exploration. Chinese Journal of Engineering Geophysics, 16(5): 713-717 (in Chinese with English abstract). [12] Liao, L., Yao, Q., Liu, J., et al., 2015. Discussion on Seismogenic Structures of the 2014 Kangding Ms6.3, Ms5.8 Earthquakes with Multiple Mainshocks. Earthquake Research in China, 31(4): 638-646 (in Chinese with English abstract). [13] Liu, Y., Hu, D. G., Xu, S. F., et al., 2020. Electrical Anisotropic Structure in the Quaternary Volcanic Region of North Hainan Island and Its Geological Implications. Earth Science, 45(1): 330-340 (in Chinese with English abstract). [14] Pan, G. T., Ren, F., Yin, F. G., et al., 2020. Key Zones of Oceanic Plate Geology and Sichuan-Tibet Railway Project. Earth Science, 45(7): 2293-2304 (in Chinese with English abstract). [15] Pan, J. W., Li, H. B., Chevalier, M. L., et al., 2020. A Newly Discovered Active Fault on the Selaha-Kangding Segment along the SE Xianshuihe Fault: The South Mugecuo Fault. Acta Geologica Sinica, 94(11): 3178-3188 (in Chinese with English abstract). [16] Parker, R. L., Booker, J. R., 1996. Optimal One-Dimensional Inversion and Bounding of Magnetotelluric Apparent Resistivity and Phase Measurements. Physics of the Earth and Planetary Interiors, 98(3-4): 269-282. https://doi.org/10.1016/S0031-9201(96)03191-3 [17] Ruan, S., Zhang, J., Sun, Y. B., et al., 2015. AMT Impedance Phase Invariant Correction Based on 3D MT Modeling Technology. Chinese Journal of Geophysics, 58(2): 685-696 (in Chinese with English abstract). [18] Tikhonov A. N., 1950. On Determining Electrical Characteristics of the Deep Layers of the Earth's crust. Doklady, 73(2): 295-297. [19] Wang, H., Wright, T. J., Biggs, J., 2009. Interseismic Slip Rate of the Northwestern Xianshuihe Fault from InSAR Data. Geophysical Research Letters, 36(3): L03302. https://doi.org/10.1029/2008GL036560 [20] Wang, Z. W., Xu, Z. X., Feng, T., et al., 2021. Geological Line Selection of Xianshuihe Structural Zone of Sichuan-Tibet Railway. Journal of Engineering Geology, 29(2): 466-477 (in Chinese with English abstract). [21] Wei, W. B., Jin, S., Ye, G. F., et al., 2003. Methods to Study Electrical Conductivity of Continental Lithosphere. Earth Science Frontiers, 10(1): 15-22 (in Chinese with English abstract). [22] Wen, X. Z., Allen, C. R., Luo, Z. L., et al., 1989. Segmentation, Geometric Features, and Their Seismotectonic Implications for the Holocene Xianshuihe Fault Zone. Acta Seismologica Sinica, 11(4): 362-372 (in Chinese with English abstract). [23] Wen, X. Z., Ma, S. L., Xu, X. W., et al., 2008. Historical Pattern and Behavior of Earthquake Ruptures along the Eastern Boundary of the Sichuan-Yunnan Faulted-Block, Southwestern China. Physics of the Earth and Planetary Interiors, 168(1-2): 16-36. https://doi.org/10.1016/j.pepi.2008.04.013 [24] Xu, X. W., Cheng, J., Xu, C., et al., 2014. Discussion on Block Kinematic Model and Future Themed Areas for Earthquake Occurrence in the Tibetan Plateau: Inspiration from the Ludian and Jinggu Earthquakes. Seismology and Geology, 36(4): 1116-1134 (in Chinese with English abstract). [25] Xu, X. W., Wu, X. Y., Yu, G. H., et al., 2017. Seismo-Geological Signatures for Identifying M≥7.0 Earthquake Risk Areas and Their Premilimary Application in Mainland China. Seismology and Geology, 39(2): 219-275 (in Chinese with English abstract). [26] Xu, X. W., Zhang, P. Z., Wen, X. Z., et al., 2005. Features of Active Tectonics and Recurrence Behaviors of Strong Earthquakes in the Western Sichuan Province and Its Adjacent Regions. Seismology and Geology, 27(3): 446-461 (in Chinese with English abstract). https://www.researchgate.net/publication/279621509_Features_of_Active_Tectonics_and_Recurrence_Behaviors_of_Strong_Earthquakes_in_the_Western_Sichuan_Province_and_Its_Adjacent_Rgeions [27] Xu, Z. Q., Li, H. B., Tang, Z. M., et al., 2011. The Transformation of the Terrain Structures of the Tibet Plateau through Large-Scale Strike-Slip Faults. Acta Petrologica Sinica, 27(11): 3157-3170 (in Chinese with English abstract). [28] Ye, T., Chen, X. B., Yan, L. J., 2013. Refined Techniques for Data Processing and Two-Dimensional Inversion in Magnetotelluric(Ⅲ): Using the Impressing Method to Construct Starting Model of 2D Magnetotelluric Inversion. Chinese Journal of Geophysics, 56(10): 3596-3606 (in Chinese with English abstract). [29] Yu, N., Hu, X. Y., Li, J., et al., 2017. Electrical Structure of the Longling Area in Western Yunnan and Its Effect on Route Selection of the Dali-Ruili Railway. Chinese Journal of Geophysics, 60(6): 2442-2455 (in Chinese with English abstract). [30] Zhang, P. Z., 2013. A Review on Active Tectonics and Deep Crustal Processes of the Western Sichuan Region, Eastern Margin of the Tibetan Plateau. Tectonophysics, 584: 7-22. https://doi.org/10.1016/j.tecto.2012.02.021 [31] Zhang, Y. Z., Replumaz, A., Leloup, P. H., et al., 2017. Cooling History of the Gongga Batholith: Implications for the Xianshuihe Fault and Miocene Kinematics of SE Tibet. Earth and Planetary Science Letters, 465: 1-15. https://doi.org/10.1016/j.epsl.2017.02.025 [32] Zhou, R. J., He, Y. L., Huang, Z. Z., et al., 2001. The Slip Rate and Strong Earthquake Recurrence Interval on the Qianning-Kangding Segment of the Xianshuihe Fault Zone. Acta Seismologica Sinica, 23(3): 250-261 (in Chinese with English abstract). [33] Zhu, G. X., 2009. Application of Audio Magnetotelluric in Geological Engineering Exploration of Railway Tunnel. Chinese Journal of Engineering Geophysics, 6(3): 294-298 (in Chinese with English abstract). [34] 陈小斌, 赵国泽, 詹艳, 2004. MT资料处理与解释的Windows可视化集成系统. 石油地球物理勘探, 39(增刊): 11-16. https://www.cnki.com.cn/Article/CJFDTOTAL-SYDQ2004S1004.htm [35] 郭长宝, 杜宇本, 张永双, 等, 2015. 川西鲜水河断裂带地质灾害发育特征与典型滑坡形成机理. 地质通报, 34(1): 121-134. doi: 10.3969/j.issn.1671-2552.2015.01.010 [36] 李海兵, 潘家伟, 孙知明, 等, 2021. 大陆构造变形与地震活动: 以青藏高原为例. 地质学报, 95(1): 194-213. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXE202101014.htm [37] 李鹏博, 李铮, 李海, 2019. 高频大地电磁法在铁路隧道勘察中的应用. 工程地球物理学报, 16(5): 713-717. doi: 10.3969/j.issn.1672-7940.2019.05.026 [38] 廖林, 姚琪, 刘杰, 等, 2015. 2014年康定Ms6.3、Ms5.8震群型地震发震机理讨论. 中国地震, 31(4): 638-646. doi: 10.3969/j.issn.1001-4683.2015.04.004 [39] 刘营, 胡道功, 许顺芳, 等, 2020. 琼北第四纪火山区电各向异性结构及其地质意义. 地球科学, 45(1): 330-340. doi: 10.3799/dqkx.2018.336 [40] 潘桂棠, 任飞, 尹福光, 等, 2020. 洋板块地质与川藏铁路工程地质关键区带. 地球科学, 45(7): 2293-2304. doi: 10.3799/dqkx.2020.070 [41] 潘家伟, 李海兵, Chevaliter, M. L., 等, 2020. 鲜水河断裂带色拉哈‒康定段新发现的活动断层: 木格措南断裂. 地质学报, 94(11): 3178-3188. doi: 10.3969/j.issn.0001-5717.2020.11.002 [42] 阮帅, 张炯, 孙远彬, 等, 2015. 基于三维正演的音频大地电磁阻抗相位不变量校正技术. 地球物理学报, 58(2): 685-696. https://www.cnki.com.cn/Article/CJFDTOTAL-DQWX201502029.htm [43] 王哲威, 徐正宣, 冯涛, 等, 2021. 川藏铁路鲜水河构造带地质选线研究. 工程地质学报, 29(2): 466-477. https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ202102016.htm [44] 魏文博, 金胜, 叶高峰, 等, 2003. 大陆岩石圈导电性的研究方法. 地学前缘, 10(1): 15-23. doi: 10.3321/j.issn:1005-2321.2003.01.003 [45] 闻学泽, Allen, C.R., 罗灼礼, 等, 1989. 鲜水河全新世断裂带的分段性、几何特征及其地震构造意义. 地震学报, 11(4): 362-372. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXB198904002.htm [46] 徐锡伟, 程佳, 许冲, 等, 2014. 青藏高原块体运动模型与地震活动主体地区讨论: 鲁甸和景谷地震的启示. 地震地质, 36(4): 1116-1134. doi: 10.3969/j.issn.0253-4967.2014.04.015 [47] 徐锡伟, 吴熙彦, 于贵华, 等, 2017. 中国大陆高震级地震危险区判定的地震地质学标志及其应用. 地震地质, 39(2): 219-275. doi: 10.3969/j.issn.0253-4967.2017.02.001 [48] 徐锡伟, 张培震, 闻学泽, 等, 2005. 川西及其邻近地区活动构造基本特征与强震复发模型. 地震地质, 27(3): 446-461. doi: 10.3969/j.issn.0253-4967.2005.03.010 [49] 许志琴, 李海兵, 唐哲民, 等, 2011. 大型走滑断裂对青藏高原地体构架的改造. 岩石学报, 27(11): 3157-3170. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201111001.htm [50] 叶涛, 陈小斌, 严良俊, 2013. 大地电磁资料精细处理和二维反演解释技术研究(三): 构建二维反演初始模型的印模法. 地球物理学报, 56(10): 3596-3606. doi: 10.6038/cjg20131034 [51] 余年, 胡祥云, 李坚, 等, 2017. 滇西龙陵地区地壳电性结构及其对大瑞铁路地质选线影响研究. 地球物理学报, 60(6): 2442-2455. https://www.cnki.com.cn/Article/CJFDTOTAL-DQWX201706033.htm [52] 周荣军, 何玉林, 黄祖智, 等, 2001. 鲜水河断裂带乾宁‒康定段的滑动速率与强震复发间隔. 地震学报, 23(3): 250-261. doi: 10.3321/j.issn:0253-3782.2001.03.004 [53] 朱光喜, 2009. 音频大地电磁在铁路隧道工程勘察中的应用. 工程地球物理学报, 6(3): 294-298. doi: 10.3969/j.issn.1672-7940.2009.03.007 -
下载:
点击查看大图
计量
- 文章访问数: 329
- HTML全文浏览量: 67
- PDF下载量: 69
- 被引次数: 0
