References#

The development of pyCSAMT v2 draws on the following literature. Papers marked with ‡ are directly cited in the codebase docstrings.


pyCSAMT — software and field applications#

[Kouadio2022]

Kouadio, K.L., Liu, R., Mi, B., Liu, C. (2022). ‡ pyCSAMT: An alternative Python toolbox for groundwater exploration using controlled source audio-frequency magnetotelluric. Journal of Applied Geophysics, 201, 104647. https://doi.org/10.1016/j.jappgeo.2022.104647

[Kouadio2023]

Kouadio, L.K., Liu, R., Malory, A.O., Liu, W., Liu, C. (2023). A novel approach for water reservoir mapping using controlled source audio-frequency magnetotelluric in Xingning area, Hunan Province, China. Geophysical Prospecting, 71(4), 668–683. https://doi.org/10.1111/1365-2478.13385

[Kouadio2024]

Kouadio, K.L., Liu, J., Liu, W., Liu, R., Boukhalfa, Z. (2024). An integrated approach for sewage diversion: Case of the Huayuan mine, Hunan Province, China. Geophysics, 89(4), B241–B256. https://doi.org/10.1190/geo2023-0332.1

[Kouadio2025]

Kouadio, K.L. (2025). k-diagram: Rethinking forecasting uncertainty via polar-based visualization. Journal of Open Source Software, 10(116), 8661. https://doi.org/10.21105/joss.08661


CSAMT / MT methodology and source effects#

[Yan2004]

Yan, S., Fu, J. (2004). ‡ An analytical method to estimate shadow and source overprint effects in CSAMT sounding. Geophysics, 69(1), 161–163. https://doi.org/10.1190/1.1649384

[Chen2005]

Chen, M., Yan, S. (2005). Analytical study on field zones, record rules, shadow and source overprint effects in CSAMT exploration. Chinese Journal of Geophysics, 48(4), 1022–1031.

[Da2016]

Da, L., Wu, X., Di, Q., Wang, G., Lv, X., Wang, R., Yang, J., Yue, M. (2016). Modeling and analysis of CSAMT field source effect and its characteristics. Journal of Geophysics and Engineering, 13(1), 49–58. https://doi.org/10.1088/1742-2132/13/1/49

[Lei2017]

Lei, D., Fayemi, B., Yang, L., Meng, X. (2017). The non-static effect of near-surface inhomogeneity on CSAMT data. Journal of Applied Geophysics, 139, 306–315. https://doi.org/10.1016/j.jappgeo.2017.03.003

[Wang2017]

Wang, K., Tan, H. (2017). Research on the forward modeling of controlled-source audio-frequency magnetotellurics in three-dimensional axial anisotropic media. Journal of Applied Geophysics, 146, 27–36. https://doi.org/10.1016/j.jappgeo.2017.08.007

[WangLin2023]

Wang, S., Lin, C. (2023). A novel approach to address source overprint and shadow effects in controlled-source audio-frequency magnetotelluric exploration. Geophysics, 88(6), E215–E230. https://doi.org/10.1190/GEO2023-0003.1

[Zhang2021]

Zhang, M., Farquharson, C.G., Liu, C. (2021). Improved CSAMT apparent resistivity pseudo sections based on the frequency and frequency-spatial gradients of electromagnetic fields. Geophysical Prospecting, 70(1), 211–229. https://doi.org/10.1111/1365-2478.13059

[Fan2022]

Fan, H., Zhang, Y., Wang, X. (2022). A novel phased-array transmitting source in controlled-source audio-frequency magnetotellurics. Journal of Geophysics and Engineering, 19, 595–614. https://doi.org/10.1093/jge/gxac023

[ZhangK2025]

Zhang, K., Zhang, R., Wang, M., Lin, Z., Zhang, Q., Jing, J., Li, F., Yang, S. (2025). Controlled source ultra-audio frequency magnetotellurics transmitter for high-resolution detection of urban shallow underground space. Measurement, 256, 118144. https://doi.org/10.1016/j.measurement.2025.118144


Airborne and passive EM methods#

[Ward1959]

Ward, S.H. (1959). ‡ AFMAG – airborne and ground. Geophysics, 24(4), 761–787. https://doi.org/10.1190/1.1438652

[Liu2018]

Liu, F., Huang, L., Pang, Y., Shi, Z., Xiao, P., Fang, G. (2018). ‡ Airborne AFMAG method motion-induced noise simulation and suppression. Journal of Applied Geophysics, 158, 129–138. https://doi.org/10.1016/j.jappgeo.2018.09.006

[Lo2008]

Lo, B., Zang, M. (2008). ‡ Numerical modeling of Z-TEM (airborne AFMAG) responses to guide exploration strategies. SEG Technical Program Expanded Abstracts, 27, 1098–1101.

[Legault2012]

Legault, J.M., Zhao, S., Fitch, R. (2012). ‡ ZTEM airborne AFMAG survey results over low sulphidation epithermal gold-silver vein systems at Gold Springs, south eastern Nevada. 22nd International Geophysical Conference and Exhibition (ASEG), Brisbane.

[Sattel2012]

Sattel, D., Witherly, K. (2012). ‡ An overview of ZTEM data interpretation tools. 2012 NFEM Forum.

[Pedersen1994]

Pedersen, L.B., Qian, W., Dynesius, L., Zhang, P. (1994). ‡ An airborne tensor VLF system. From concept to realization. Geophysical Prospecting, 42(8), 863–883.

[wang2025]

Wang, Y., Qu, J., Chen, T., Zhou, S., Li, Y. (2025). ‡ Studies of three dimensional staggered-grid finite difference for Z-axis tipper electromagnetic numerical simulation. Frontiers in Earth Science, 13, 1496312. https://doi.org/10.3389/feart.2025.1496312

[Prikhodko2022]

Prikhodko, A., Bagrianski, A., Kuzmin, P., Sirohey, A. (2022). ‡ Natural field airborne electromagnetics – history of development and current exploration capabilities. Minerals, 12(5), 583. https://doi.org/10.3390/min12050583

[Sattel2019]

Sattel, D., Witherly, K., Kaminski, V. (2019). ‡ A brief analysis of MobileMT data. SEG International Exposition and Annual Meeting, D043S102R007.

[Zhdanov2024]

Zhdanov, M.S., Gribenko, A., Prikhodko, A., Sabra, H.E., Jorgensen, M., Cox, L.H. (2024). ‡ Three-dimensional MobileMT and TMI data inversions for mineral exploration. 1st ASEG DISCOVER Symposium.

[Swift1967]

Swift, C.M. (1967). ‡ A magnetotelluric investigation of an electrical conductivity anomaly in the southwestern United States. PhD thesis, MIT.


Tensor decomposition and dimensionality#

[Caldwell2004]

Caldwell, T.G., Bibby, H.M., Brown, C. (2004). ‡ The magnetotelluric phase tensor. Geophysical Journal International, 158(2), 457–469. https://doi.org/10.1111/j.1365-246X.2004.02281.x

[GroomBailey1989]

Groom, R.W., Bailey, R.C. (1989). ‡ Decomposition of magnetotelluric impedance tensors in the presence of local three-dimensional galvanic distortion. Journal of Geophysical Research: Solid Earth, 94(B2), 1913–1925. https://doi.org/10.1029/JB094iB02p01913


Deep learning and AI-assisted inversion#

[Liu2021]

Liu, Z., Chen, H., Ren, Z., Tang, J., Xu, Z., Chen, Y., Liu, X. (2021). ‡ Deep learning audio magnetotellurics inversion using residual-based deep convolution neural network. Journal of Applied Geophysics, 188, 104309. https://doi.org/10.1016/j.jappgeo.2021.104309

[Guo2021]

Guo, R., Yao, H.M., Li, M., Ng, M.K.P., Jiang, L., Abubakar, A. (2021). ‡ Joint inversion of audio-magnetotelluric and seismic travel time data with deep learning constraint. IEEE Transactions on Geoscience and Remote Sensing, 59(9), 7982–7995. https://doi.org/10.1109/TGRS.2020.3032743

[Oh2019]

Oh, S., Noh, K., Yoon, D., Seol, S.J., Byun, J. (2019). Salt delineation from electromagnetic data using convolutional neural networks. IEEE Geoscience and Remote Sensing Letters, 16(8), 1202–1206. https://doi.org/10.1109/LGRS.2018.2877155

[Oh2020]

Oh, S., Noh, K., Seol, S.J., Byun, J. (2020). ‡ Cooperative deep learning inversion of controlled-source electromagnetic data for salt delineation. Geophysics, 85(4), E121–E137. https://doi.org/10.1190/GEO2019-0532.1

[Moghadas2020]

Moghadas, D. (2020). One-dimensional deep learning inversion of electromagnetic induction data using convolutional neural network. Geophysical Journal International, 223(1), 198–212. https://doi.org/10.1093/gji/ggaa202

[Puzyrev2019]

Puzyrev, V., Meka, S., Swidinsky, A. (2019). Deep convolutional neural networks for 1D inversion of electromagnetic data. 81st EAGE Conference & Exhibition, London. https://doi.org/10.3997/2214-4609.201900685

[Puzyrev2021]

Puzyrev, V., Swidinsky, A. (2021). ‡ Inversion of 1D frequency- and time-domain electromagnetic data with convolutional neural networks. Computers & Geosciences, 149, 104681. https://doi.org/10.1016/j.cageo.2021.104681


Inversion algorithms and rock physics#

[deGrootHedlin1990]

deGroot-Hedlin, C., Constable, S. (1990). ‡ Occam’s inversion to generate smooth, two-dimensional models from magnetotelluric data. Geophysics, 55(12), 1613–1624. https://doi.org/10.1190/1.1442303

[Kelbert2014]

Kelbert, A., Meqbel, N., Egbert, G.D., Tandon, K. (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

[Palacky1988]

Palacky, G.J. (1988). ‡ Resistivity characteristics of geologic targets. In: Nabighian, M.N. (Ed.), Electromagnetic Methods in Applied Geophysics, Vol. 1. SEG, Tulsa, pp. 53–129.


Data standards#

[SEG1991]

Society of Exploration Geophysicists (1991). MT/EMAP Data Interchange Standard (revised edition). SEG Technical Standards Committee, Tulsa, Oklahoma. (Original standard adopted 14 December 1987.)

[WardHohmann1988]

Ward, S.H., Hohmann, G.W. (1988). ‡ Electromagnetic theory for geophysical applications. In: Nabighian, M.N. (Ed.), Electromagnetic Methods in Applied Geophysics, Vol. 1. SEG, Tulsa, pp. 131–311.

[NabighianMacnae1991]

Nabighian, M.N., Macnae, J.C. (1991). ‡ Time domain electromagnetic prospecting methods. In: Nabighian, M.N. (Ed.), Electromagnetic Methods in Applied Geophysics, Vol. 2. SEG, Tulsa, pp. 427–520.

[Christiansen2009]

Christiansen, A.V., Auken, E., Sorensen, K. (2009). ‡ The transient electromagnetic method. In: Kirsch, R. (Ed.), Groundwater Geophysics: A Tool for Hydrogeology, 2nd ed. Springer, pp. 179–226.


Bundled example datasets#

The real field surveys bundled with pyCSAMT for docstrings, tests, and documentation examples come from published field studies. Please cite the relevant paper below if you reuse this data beyond exploring pyCSAMT itself.

[Kouabena2025]

Kouabena, K.A.W., Zhou, J., Chen, R., Yin, L., Cai, H., Lu, Z., Gu, J., Yu, W. (2025). Enhanced prediction of deep-seated Cu-Mo porphyry mineralization: A comprehensive interpretation based on 2D inversion of audio-magnetotelluric data. Ore Geology Reviews, 185, 106798. https://doi.org/10.1016/j.oregeorev.2025.106798

(Field dataset: data/AMT/WILLY_DATA/ — see the README there for which lines are bundled.)

[Kouadio2020]

Kouadio, K.L., Xu, Y., Liu, C., Boukhalfa, Z. (2020). Two-dimensional inversion of CSAMT data and three-dimensional geological mapping for groundwater exploration in Tongkeng Area, Hunan Province, China. Journal of Applied Geophysics, 104204. https://doi.org/10.1016/j.jappgeo.2020.104204

(Field dataset: data/CSAMT/ — see the README there for survey details.)