none 10.1190/geo2024-0107.1 Society of Exploration Geophysicists Society of Exploration Geophysicists 186 166933724 5981 2025121212414855400 10.1190 2025-12-12T17:41:55Z 2024-11-05T12:16:35Z 3 Geophysics 0016-8033 1942-2156 01 03 2025 90 2 Charles L. Bérubé Polytechnique Montréal 1 , Civil, Geological and Mining Engineering Department, Montréal, Canada. charles.berube@polymtl.ca (corresponding author) http://orcid.org/0000-0002-5438-0382 Jean-Luc Gagnon Polytechnique Montréal 2 , Engineering Physics Department, Montréal, Canada. jean-luc.gagnon@polymtl.ca http://orcid.org/0009-0009-5264-352X ABSTRACT Interpreting 3D induced polarization (IP) data requires rock-physics models that reflect the omnipresent anisotropy of the earth’s crust. The generalized effective medium theory of induced polarization (GEMTIP) can model the IP signatures of rocks with polarizable mineral inclusions. However, it is computationally demanding because it requires numerically solving the depolarization tensors of each inclusion. We aim to streamline GEMTIP simulations by (1) integrating the anisotropic background conductivity and triaxial ellipsoidal inclusions in the model and (2) estimating the depolarization tensors with a neural network. We validate the neural network predictions against the known solutions for spherical and spheroidal inclusions, and we test our method using data from an actual rock sample. The neural network indicates a relative sensitivity of 56% to the inclusion shape and 44% to the host rock anisotropy and is up to 100,000 times faster than numerical integration. We release the pretrained neural network implementation as an open-source Python package, thereby providing a new method to interpret the IP signatures of anisotropic rocks. 01 10 2025 01 03 2025 C37 C50 Fonds de recherche du Québec - Nature et technologies 326054 Natural Sciences and Engineering Research Council of Canada http://dx.doi.org/10.13039/501100000038 1 10.1190/crossmark-policy library.seg.org true 2024-02-16 2024-09-09 2024-10-20 2025-01-10 Fonds de recherche du Québec - Nature et technologies 326054 Natural Sciences and Engineering Research Council of Canada http://dx.doi.org/10.13039/501100000038 10.1190/geo2024-0107.1 https://pubs.geoscienceworld.org/geophysics/article/90/2/C37/651367/Anisotropic-induced-polarization-modeling-with https://pubs.geoscienceworld.org/seg/geophysics/article-pdf/90/2/C37/7093536/geo-2024-0107.1.pdf https://pubs.geoscienceworld.org/seg/geophysics/article-pdf/90/2/C37/7093536/geo-2024-0107.1.pdf https://pubs.geoscienceworld.org/geophysics/article/90/2/c37/651367/anisotropic-induced-polarization-modeling-with Exploration Geophysics Aguilef 48 353 2017 10.1071/EG15077 Relationship between bulk mineralogy and induced polarisation responses in iron oxide-copper-gold and porphyry copper mineralisation, northern Chile Minerals Alfouzan 10 2020 10.3390/min10090769 Spectral induced polarization survey with distributed array system for mineral exploration: Case study in Saudi Arabia 1063-7842 Technical Physics Apresyan 59 1760 2014 10.1134/S1063784214120020 On depolarization factors of anisotropic ellipsoids in an anisotropic medium Environmental Earth Sciences Azffri 81 2022 10.1007/s12665-022-10284-1 Electrical resistivity tomography and induced polarization study for groundwater exploration in the agricultural development areas of Brunei Darussalam Bérubé C. 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