地质科技通报 (Mar 2024)

Two-dimensional magnetotelluric inversion method based on deep learning

  • Fang WANG,
  • Jie XIONG,
  • Huixiao TIAN,
  • Siping LI,
  • Jiashuai KANG

DOI
https://doi.org/10.19509/j.cnki.dzkq.tb20220471
Journal volume & issue
Vol. 43, no. 2
pp. 344 – 354

Abstract

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Objective The inversion of magnetotelluric sounding data to improve the accuracy of data interpretation has always been an essential topic in magnetotelluric sounding. Methods To address the problems of traditional magnetotelluric inversion methods, such as the dependence of the initial model and the ease of falling into a local optimum, this paper proposes a magnetotelluric inversion method based on deep learning.The method begins with the design of the GoogLeNetINV neural network. Then, various geoelectric models are constructed, and apparent resistivity data are extracted via forward modelling in the TM mode, constituting the training dataset. Additionally, the neural network is trained with the training dataset, and the network parameters are adjusted. Finally, the apparent resistivity data are input into the trained GoogLeNetINV neural network to directly obtain the inversion result. Results The experimental results reveal that the location and resistivity data of the "unlearned" geoelectric model can be inverted quickly and accurately, and the model has good generalization ability. The use of noise data can still yield good inversion results and a certain anti-noise ability. Conclusion The neural network is applied to the field data processing of the Bendigo Zone, and the resistivity model derived through inversion is consistent with the seismic interpretation. Consequently, the magnetotelluric inversion method based on deep learning can effectively solve the magnetotelluric inversion problem.

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