Three-dimensional time-lapse inversion of transient electromagnetic data, with application at an Icelandic geothermal site
Transient electromagnetic (TEM) is an efficient non-invasive method to map electrical conductivity distribution in the subsurface. This paper presents an inversion scheme for 3-D TEM time-lapse (TL) data using a generalized minimum support (MS) norm and its application to monitoring conductivity cha...
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Online Access: | https://hdl.handle.net/2434/969828 https://doi.org/10.1093/gji/ggac206 |
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ftunivmilanoair:oai:air.unimi.it:2434/969828 2024-02-11T10:05:16+01:00 Three-dimensional time-lapse inversion of transient electromagnetic data, with application at an Icelandic geothermal site Longying Xiao Gianluca Fiandaca Pradip K Maurya Anders Vest Christiansen Léa Lévy L. Xiao G. Fiandaca P. K Maurya A. Vest Christiansen L. Lévy 2022 https://hdl.handle.net/2434/969828 https://doi.org/10.1093/gji/ggac206 eng eng Blackwell Science Limited info:eu-repo/semantics/altIdentifier/wos/WOS:000829021000010 volume:231 issue:1 firstpage:584 lastpage:596 numberofpages:13 journal:GEOPHYSICAL JOURNAL INTERNATIONAL https://hdl.handle.net/2434/969828 doi:10.1093/gji/ggac206 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85134391325 info:eu-repo/semantics/closedAccess Hydrogeophysic Controlled source electromagnetics (CSEM) Inverse theory Time-lapse inversion Time-domain electromagnetic Settore GEO/11 - Geofisica Applicata info:eu-repo/semantics/article 2022 ftunivmilanoair https://doi.org/10.1093/gji/ggac206 2024-01-23T23:13:14Z Transient electromagnetic (TEM) is an efficient non-invasive method to map electrical conductivity distribution in the subsurface. This paper presents an inversion scheme for 3-D TEM time-lapse (TL) data using a generalized minimum support (MS) norm and its application to monitoring conductivity changes over time. In particular, two challenges for TL TEM applications are addressed: (i) the survey repetition with slightly different acquisition position, that is, because systems are not installed and (ii) non-optimal data coverage above the TL anomalies, for instance, due to the presence of infrastructure that limits the acquisition layout because of coupling. To address these issues, we developed a new TEM TL inversion scheme with the following features: (1) a multimesh approach for model definition and forward computations, which allows for seamless integration of data sets with different acquisition layouts; (2) 3-D sensitivity calculation during the inversion, which allows retrieving conductivity changes in-between TEM soundings and (3) simultaneous inversion of two data sets at once, imposing TL constraints defined in terms of a generalized MS norm, which ensures compact TL changes. We assess the relevance of our implementations through a synthetic example and a field example. In the synthetic example, we study the capability of the inversion scheme to retrieve compact time-lapse changes despite slight changes in the acquisition layout and the effect of data coverage on the retrieval of TL changes. Results from the synthetic tests are used for interpreting field data, which consists of two TEM data sets collected in 2019 and 2020 at the Nesjavellir high-temperature geothermal site (Iceland) within a monitoring project of H2S sequestration. Furthermore, the field example illustrates the effect of the trade-off between data misfit and TL constraints in the inversion objective function, using the tuning settings of the generalized MS norm. Based on the results from both the synthetic and field cases, we show ... Article in Journal/Newspaper Iceland The University of Milan: Archivio Istituzionale della Ricerca (AIR) Nesjavellir ENVELOPE(-21.251,-21.251,64.115,64.115) Geophysical Journal International 231 1 584 596 |
institution |
Open Polar |
collection |
The University of Milan: Archivio Istituzionale della Ricerca (AIR) |
op_collection_id |
ftunivmilanoair |
language |
English |
topic |
Hydrogeophysic Controlled source electromagnetics (CSEM) Inverse theory Time-lapse inversion Time-domain electromagnetic Settore GEO/11 - Geofisica Applicata |
spellingShingle |
Hydrogeophysic Controlled source electromagnetics (CSEM) Inverse theory Time-lapse inversion Time-domain electromagnetic Settore GEO/11 - Geofisica Applicata Longying Xiao Gianluca Fiandaca Pradip K Maurya Anders Vest Christiansen Léa Lévy Three-dimensional time-lapse inversion of transient electromagnetic data, with application at an Icelandic geothermal site |
topic_facet |
Hydrogeophysic Controlled source electromagnetics (CSEM) Inverse theory Time-lapse inversion Time-domain electromagnetic Settore GEO/11 - Geofisica Applicata |
description |
Transient electromagnetic (TEM) is an efficient non-invasive method to map electrical conductivity distribution in the subsurface. This paper presents an inversion scheme for 3-D TEM time-lapse (TL) data using a generalized minimum support (MS) norm and its application to monitoring conductivity changes over time. In particular, two challenges for TL TEM applications are addressed: (i) the survey repetition with slightly different acquisition position, that is, because systems are not installed and (ii) non-optimal data coverage above the TL anomalies, for instance, due to the presence of infrastructure that limits the acquisition layout because of coupling. To address these issues, we developed a new TEM TL inversion scheme with the following features: (1) a multimesh approach for model definition and forward computations, which allows for seamless integration of data sets with different acquisition layouts; (2) 3-D sensitivity calculation during the inversion, which allows retrieving conductivity changes in-between TEM soundings and (3) simultaneous inversion of two data sets at once, imposing TL constraints defined in terms of a generalized MS norm, which ensures compact TL changes. We assess the relevance of our implementations through a synthetic example and a field example. In the synthetic example, we study the capability of the inversion scheme to retrieve compact time-lapse changes despite slight changes in the acquisition layout and the effect of data coverage on the retrieval of TL changes. Results from the synthetic tests are used for interpreting field data, which consists of two TEM data sets collected in 2019 and 2020 at the Nesjavellir high-temperature geothermal site (Iceland) within a monitoring project of H2S sequestration. Furthermore, the field example illustrates the effect of the trade-off between data misfit and TL constraints in the inversion objective function, using the tuning settings of the generalized MS norm. Based on the results from both the synthetic and field cases, we show ... |
author2 |
L. Xiao G. Fiandaca P. K Maurya A. Vest Christiansen L. Lévy |
format |
Article in Journal/Newspaper |
author |
Longying Xiao Gianluca Fiandaca Pradip K Maurya Anders Vest Christiansen Léa Lévy |
author_facet |
Longying Xiao Gianluca Fiandaca Pradip K Maurya Anders Vest Christiansen Léa Lévy |
author_sort |
Longying Xiao |
title |
Three-dimensional time-lapse inversion of transient electromagnetic data, with application at an Icelandic geothermal site |
title_short |
Three-dimensional time-lapse inversion of transient electromagnetic data, with application at an Icelandic geothermal site |
title_full |
Three-dimensional time-lapse inversion of transient electromagnetic data, with application at an Icelandic geothermal site |
title_fullStr |
Three-dimensional time-lapse inversion of transient electromagnetic data, with application at an Icelandic geothermal site |
title_full_unstemmed |
Three-dimensional time-lapse inversion of transient electromagnetic data, with application at an Icelandic geothermal site |
title_sort |
three-dimensional time-lapse inversion of transient electromagnetic data, with application at an icelandic geothermal site |
publisher |
Blackwell Science Limited |
publishDate |
2022 |
url |
https://hdl.handle.net/2434/969828 https://doi.org/10.1093/gji/ggac206 |
long_lat |
ENVELOPE(-21.251,-21.251,64.115,64.115) |
geographic |
Nesjavellir |
geographic_facet |
Nesjavellir |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000829021000010 volume:231 issue:1 firstpage:584 lastpage:596 numberofpages:13 journal:GEOPHYSICAL JOURNAL INTERNATIONAL https://hdl.handle.net/2434/969828 doi:10.1093/gji/ggac206 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85134391325 |
op_rights |
info:eu-repo/semantics/closedAccess |
op_doi |
https://doi.org/10.1093/gji/ggac206 |
container_title |
Geophysical Journal International |
container_volume |
231 |
container_issue |
1 |
container_start_page |
584 |
op_container_end_page |
596 |
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1790602196270710784 |