{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,8]],"date-time":"2026-03-08T22:47:23Z","timestamp":1773010043951,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,3,30]],"date-time":"2023-03-30T00:00:00Z","timestamp":1680134400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Program of China","award":["2021YFB3202104"],"award-info":[{"award-number":["2021YFB3202104"]}]},{"name":"National Key Research and Development Program of China","award":["42030806"],"award-info":[{"award-number":["42030806"]}]},{"name":"National Key Research and Development Program of China","award":["42074120"],"award-info":[{"award-number":["42074120"]}]},{"name":"National Key Research and Development Program of China","award":["42174167"],"award-info":[{"award-number":["42174167"]}]},{"name":"National Key Research and Development Program of China","award":["42274093"],"award-info":[{"award-number":["42274093"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2021YFB3202104"],"award-info":[{"award-number":["2021YFB3202104"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["42030806"],"award-info":[{"award-number":["42030806"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["42074120"],"award-info":[{"award-number":["42074120"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["42174167"],"award-info":[{"award-number":["42174167"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["42274093"],"award-info":[{"award-number":["42274093"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The surface-to-borehole transient electromagnetic (SBTEM) method can provide images at higher resolution for deep earth because its receivers are close to targets. However, as usually the boreholes distribute sparsely, the limited EM data can result in an \u201cequivalent trap\u201d in SBTEM inversions, i.e., the data are well-fitted, but the model is not properly recovered. To overcome this non-unique problem, we propose a dual-mesh three-dimensional (3D) SBTEM inversion scheme. We first use a coarse mesh to obtain a rough resistivity distribution near the borehole, and then we map the coarse mesh attribute into a fine one and capture details from the fine mesh inversion. We test our method on both synthetic data and survey data acquired in Daye, Hubei Province, China. Numerical experiments show that our dual-mesh inversion strategy can better recover the location and resistivity of targets.<\/jats:p>","DOI":"10.3390\/rs15071845","type":"journal-article","created":{"date-parts":[[2023,3,30]],"date-time":"2023-03-30T05:22:14Z","timestamp":1680153734000},"page":"1845","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Three-Dimensional Dual-Mesh Inversions for Sparse Surface-to-Borehole TEM Data"],"prefix":"10.3390","volume":"15","author":[{"given":"Luyuan","family":"Wang","sequence":"first","affiliation":[{"name":"College of Geo-Exploration Sciences and Technology, Jilin University, Changchun 130026, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3634-9832","authenticated-orcid":false,"given":"Yunhe","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Geo-Exploration Sciences and Technology, Jilin University, Changchun 130026, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Changchun","family":"Yin","sequence":"additional","affiliation":[{"name":"College of Geo-Exploration Sciences and Technology, Jilin University, Changchun 130026, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yang","family":"Su","sequence":"additional","affiliation":[{"name":"College of Geo-Exploration Sciences and Technology, Jilin University, Changchun 130026, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiuyan","family":"Ren","sequence":"additional","affiliation":[{"name":"College of Geo-Exploration Sciences and Technology, Jilin University, Changchun 130026, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bo","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Geo-Exploration Sciences and Technology, Jilin University, Changchun 130026, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,30]]},"reference":[{"key":"ref_1","unstructured":"Li, J. (2015). Inversion Algorithms for Electromagnetic Problems in Well: Numerical Examples in Reservoir Target Detection. [Ph.D. Thesis, China University of Geosciences]."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"90","DOI":"10.1190\/1.1442581","article-title":"A theoretical study of surface-to-borehole electromagnetic logging in cased holes","volume":"54","author":"Augustin","year":"1989","journal-title":"Geophysics"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1016\/0016-7142(81)90040-5","article-title":"Directional EM-measurements in boreholes","volume":"19","author":"Malmqvist","year":"1981","journal-title":"Geoexploration"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1071\/EG987313","article-title":"The downhole EM response of an intersected massive sulphide deposit, South Australia","volume":"18","author":"Lane","year":"1987","journal-title":"Explor. Geophys."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1071\/EG989065","article-title":"DHEM: The Que-Hellyer Volcanics experience","volume":"20","author":"Silic","year":"1989","journal-title":"Explor. Geophys."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"106","DOI":"10.1071\/EG995106","article-title":"Petrophysical characteristics of BIF-hosted gold deposits and the application of downhole EM to their exploration, with examples from Hill 50 gold mine, Mt Magnet, Western Australia","volume":"26","author":"Vella","year":"1995","journal-title":"Explor. Geophys."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"248","DOI":"10.1071\/EG15096","article-title":"Discovery of the Eureka volcanogenic massive sulphide lens using downhole electromagnetics","volume":"47","author":"Paggi","year":"2016","journal-title":"Explor. Geophys."},{"key":"ref_8","first-page":"24","article-title":"Imaging method in surface-to-borehole electromagnetic system","volume":"23","author":"Wei","year":"1999","journal-title":"Shi You Da Xue Xue Bao"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1090","DOI":"10.1190\/1.1487056","article-title":"Inversions of surface and borehole data from a large-loop transient electromagnetic system over a 1-D earth","volume":"66","author":"Zhang","year":"2001","journal-title":"Geophysics"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"4207","DOI":"10.1007\/s00024-020-02477-1","article-title":"A Surface-to-Borehole TEM System Based on Grounded-wire Sources: Synthetic Modeling and Data Inversion","volume":"177","author":"Chen","year":"2020","journal-title":"Pure Appl. Geophys."},{"key":"ref_11","first-page":"1969","article-title":"Analysis on the full-component response and detectability of electric source surface-to-borehole TEM method","volume":"62","author":"Chen","year":"2019","journal-title":"Acta Geophys. Sin."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1133","DOI":"10.1190\/1.2035909","article-title":"The electromagnetic response of a conductive inhomogeneity in a layered earth","volume":"41","author":"Lajoie","year":"1976","journal-title":"Geophysics"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1469","DOI":"10.1190\/1.1442427","article-title":"The borehole transient electromagnetic response of a three-dimensional fracture zone in a conductive half-space","volume":"53","author":"West","year":"1988","journal-title":"Geophysics"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"861","DOI":"10.1190\/1.1441732","article-title":"The influence of a conductive host on two-dimensional borehole transient electromagnetic responses","volume":"49","author":"Eaton","year":"1984","journal-title":"Geophysics"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1111\/j.1365-246X.2011.05127.x","article-title":"Three-dimensional adaptive higher order finite element simulation for geo-electromagnetics\u2014A marine CSEM example","volume":"187","author":"Christoph","year":"2011","journal-title":"Geophys. J. Int."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1016\/j.jappgeo.2016.08.002","article-title":"3D time-domain airborne EM forward modeling with topography","volume":"134","author":"Yin","year":"2016","journal-title":"J. Appl. Geophys."},{"key":"ref_17","first-page":"2449","article-title":"Three-dimensional magnetotelluric inversion with surface topography based on the vector finite element method","volume":"63","author":"Gu","year":"2020","journal-title":"Acta Geophys. Sin."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"74","DOI":"10.1093\/gji\/ggv410","article-title":"3-D magnetotelluric inversion including topography using deformed hexahedral edge finite elements and direct solvers parallelized on SMP computers; Part I, Forward problem and parameter Jacobians","volume":"204","author":"Kordy","year":"2016","journal-title":"Geophys. J. Int."},{"key":"ref_19","unstructured":"Um, E.S. (2011). Three-Dimensional Finite-Element Time-Domain Modeling of the Marine Controlled-Source Electromagnetic Method. [Ph.D. Thesis, Stanford University]."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"E47","DOI":"10.1190\/geo2012-0131.1","article-title":"Three dimensional inversion of multisource time domain electromagnetic data","volume":"78","author":"Oldenburg","year":"2013","journal-title":"Geophysics"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"E117","DOI":"10.1190\/geo2017-0216.1","article-title":"A finite-element time-domain forward solver for electromagnetic methods with complex-shaped loop sources","volume":"83","author":"Li","year":"2018","journal-title":"Geophysics"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"544","DOI":"10.1139\/cjes-2018-0069","article-title":"Deep mineral exploration using multi-scale electromagnetic geophysics; the Lalor massive sulphide deposit case study","volume":"56","author":"Yang","year":"2019","journal-title":"Can. J. Earth Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"B23","DOI":"10.1190\/geo2011-0194.1","article-title":"Three-dimensional inversion of airborne time-domain electromagnetic data with applications to a porphyry deposit","volume":"77","author":"Yang","year":"2012","journal-title":"Geophysics"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1007\/s11770-021-0863-9","article-title":"Three-dimensional forward modeling for the SBTEM method using an unstructured finite-element method","volume":"18","author":"Wang","year":"2021","journal-title":"Appl. Geophys."},{"key":"ref_25","first-page":"3167","article-title":"3D inversions of time-domain marine EM data based on unstructured finite-element method","volume":"63","author":"Hui","year":"2020","journal-title":"Acta Geophys. Sin."},{"key":"ref_26","first-page":"2566","article-title":"Three-dimensional ground TEM inversion over a topographic earth considering ramp time","volume":"64","author":"Qi","year":"2021","journal-title":"Acta Geophys. Sin."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"571","DOI":"10.1093\/gji\/ggw290","article-title":"MARE2DEM: A 2-D inversion code for controlled-source electromagnetic and magnetotelluric data","volume":"207","author":"Key","year":"2016","journal-title":"Geophys. J. Int."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1093\/gji\/ggz014","article-title":"3-D inversion of transient EM data with topography using unstructured tetrahedral grids","volume":"217","author":"Liu","year":"2019","journal-title":"Geophys. J. Int."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1145\/2629697","article-title":"TetGen, a Delaunay-Based Quality Tetrahedral Mesh Generator","volume":"41","author":"Si","year":"2015","journal-title":"ACM Trans. Math. Softw."},{"key":"ref_30","unstructured":"Jin, J.-M. (2002). The Finite Element Method in Electromagnetics, Wiley. [2nd ed.]."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"F115","DOI":"10.1190\/1.3473694","article-title":"3D time-domain simulation of electromagnetic diffusion phenomena; a finite-element electric-field approach","volume":"75","author":"Um","year":"2010","journal-title":"Geophysics"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1137\/S0895479899358194","article-title":"A Fully Asynchronous Multifrontal Solver Using Distributed Dynamic Scheduling","volume":"23","author":"Amestoy","year":"2001","journal-title":"SIAM J. Matrix Anal. Appl."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/15\/7\/1845\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:07:04Z","timestamp":1760123224000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/15\/7\/1845"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,3,30]]},"references-count":32,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2023,4]]}},"alternative-id":["rs15071845"],"URL":"https:\/\/doi.org\/10.3390\/rs15071845","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,3,30]]}}}