Interpreting Inverse Magnetic Fabric in Miocene Dikes From Eastern Iceland
International audience Anisotropy of Magnetic Susceptibility (AMS) is a valid tool to investigate magma flow direction within dikes. However, geometrically inverse magnetic fabric characterized by maximum magnetic susceptibility axis (kmax) perpendicular to the dike wall may complicate the interpret...
Published in: | Journal of Geophysical Research: Solid Earth |
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Format: | Article in Journal/Newspaper |
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2020
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Online Access: | https://hal-insu.archives-ouvertes.fr/insu-03721893 https://hal-insu.archives-ouvertes.fr/insu-03721893/document https://hal-insu.archives-ouvertes.fr/insu-03721893/file/JGR%20Solid%20Earth%20-%202020%20-%20Trippanera%20-%20Interpreting%20Inverse%20Magnetic%20Fabric%20in%20Miocene%20Dikes%20From%20Eastern%20Iceland.pdf https://doi.org/10.1029/2020JB020306 |
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ftccsdartic:oai:HAL:insu-03721893v1 2023-06-11T04:13:04+02:00 Interpreting Inverse Magnetic Fabric in Miocene Dikes From Eastern Iceland Trippanera, D. Porreca, M. Urbani, S. Kissel, C. Winkler, A. Sagnotti, L. Nazzareni, S. Acocella, V. Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) 2020 https://hal-insu.archives-ouvertes.fr/insu-03721893 https://hal-insu.archives-ouvertes.fr/insu-03721893/document https://hal-insu.archives-ouvertes.fr/insu-03721893/file/JGR%20Solid%20Earth%20-%202020%20-%20Trippanera%20-%20Interpreting%20Inverse%20Magnetic%20Fabric%20in%20Miocene%20Dikes%20From%20Eastern%20Iceland.pdf https://doi.org/10.1029/2020JB020306 en eng HAL CCSD American Geophysical Union info:eu-repo/semantics/altIdentifier/doi/10.1029/2020JB020306 insu-03721893 https://hal-insu.archives-ouvertes.fr/insu-03721893 https://hal-insu.archives-ouvertes.fr/insu-03721893/document https://hal-insu.archives-ouvertes.fr/insu-03721893/file/JGR%20Solid%20Earth%20-%202020%20-%20Trippanera%20-%20Interpreting%20Inverse%20Magnetic%20Fabric%20in%20Miocene%20Dikes%20From%20Eastern%20Iceland.pdf BIBCODE: 2020JGRB.12520306T doi:10.1029/2020JB020306 http://hal.archives-ouvertes.fr/licences/copyright/ info:eu-repo/semantics/OpenAccess ISSN: 2169-9313 EISSN: 2169-9356 Journal of Geophysical Research : Solid Earth https://hal-insu.archives-ouvertes.fr/insu-03721893 Journal of Geophysical Research : Solid Earth, 2020, 125, ⟨10.1029/2020JB020306⟩ AMS inverse fabric single domain Iceland dikes volcanic system [SDU]Sciences of the Universe [physics] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2020 ftccsdartic https://doi.org/10.1029/2020JB020306 2023-05-06T23:26:40Z International audience Anisotropy of Magnetic Susceptibility (AMS) is a valid tool to investigate magma flow direction within dikes. However, geometrically inverse magnetic fabric characterized by maximum magnetic susceptibility axis (kmax) perpendicular to the dike wall may complicate the interpretation of flow trajectories. To better understand the nature of this fabric, we present a multiscale study on 19 dikes (383 samples) in the Miocene Alftafjordur volcanic system (Iceland), where 80% of the samples show a geometrically inverse magnetic fabric. We carried out (1) AMS measurements at different magnetic fields and temperatures, along with Anisotropy of Anhysteretic Remanent Magnetization (AARM) analysis; (2) hysteresis loops and FORC diagrams; (3) thin section analysis; (4) structural fieldwork. A variable Ti-content (0.1 < x < 0.6, Fe 3-x Ti x O 4 ) titanomagnetite is the main magnetic carrier, and the contribution of the paramagnetic elongated crystals to the magnetic fabric is negligible. Single domain is not the prevailing domain state of the magnetic particles, suggesting that its occurrence cannot be the main cause for the inverse fabric. AMS analysis at different fields and temperatures along with AARM allow us to exclude any mineral phase change of the titanomagnetite across the dike. Nevertheless, kmax is parallel to a diffuse horizontal column-like fracture pattern perpendicularly oriented with respect to the dike strike. This suggests that the Ti-magnetite mineral orientation during dike cooling was affected by the fracture network progressively developing columnar basalts. This study demonstrates that the interpretation of AMS data on old and deep volcanic bodies is not straightforward and observations at different scales are required. Article in Journal/Newspaper Iceland Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) Journal of Geophysical Research: Solid Earth 125 11 |
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Open Polar |
collection |
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
op_collection_id |
ftccsdartic |
language |
English |
topic |
AMS inverse fabric single domain Iceland dikes volcanic system [SDU]Sciences of the Universe [physics] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
AMS inverse fabric single domain Iceland dikes volcanic system [SDU]Sciences of the Universe [physics] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Trippanera, D. Porreca, M. Urbani, S. Kissel, C. Winkler, A. Sagnotti, L. Nazzareni, S. Acocella, V. Interpreting Inverse Magnetic Fabric in Miocene Dikes From Eastern Iceland |
topic_facet |
AMS inverse fabric single domain Iceland dikes volcanic system [SDU]Sciences of the Universe [physics] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience Anisotropy of Magnetic Susceptibility (AMS) is a valid tool to investigate magma flow direction within dikes. However, geometrically inverse magnetic fabric characterized by maximum magnetic susceptibility axis (kmax) perpendicular to the dike wall may complicate the interpretation of flow trajectories. To better understand the nature of this fabric, we present a multiscale study on 19 dikes (383 samples) in the Miocene Alftafjordur volcanic system (Iceland), where 80% of the samples show a geometrically inverse magnetic fabric. We carried out (1) AMS measurements at different magnetic fields and temperatures, along with Anisotropy of Anhysteretic Remanent Magnetization (AARM) analysis; (2) hysteresis loops and FORC diagrams; (3) thin section analysis; (4) structural fieldwork. A variable Ti-content (0.1 < x < 0.6, Fe 3-x Ti x O 4 ) titanomagnetite is the main magnetic carrier, and the contribution of the paramagnetic elongated crystals to the magnetic fabric is negligible. Single domain is not the prevailing domain state of the magnetic particles, suggesting that its occurrence cannot be the main cause for the inverse fabric. AMS analysis at different fields and temperatures along with AARM allow us to exclude any mineral phase change of the titanomagnetite across the dike. Nevertheless, kmax is parallel to a diffuse horizontal column-like fracture pattern perpendicularly oriented with respect to the dike strike. This suggests that the Ti-magnetite mineral orientation during dike cooling was affected by the fracture network progressively developing columnar basalts. This study demonstrates that the interpretation of AMS data on old and deep volcanic bodies is not straightforward and observations at different scales are required. |
author2 |
Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Trippanera, D. Porreca, M. Urbani, S. Kissel, C. Winkler, A. Sagnotti, L. Nazzareni, S. Acocella, V. |
author_facet |
Trippanera, D. Porreca, M. Urbani, S. Kissel, C. Winkler, A. Sagnotti, L. Nazzareni, S. Acocella, V. |
author_sort |
Trippanera, D. |
title |
Interpreting Inverse Magnetic Fabric in Miocene Dikes From Eastern Iceland |
title_short |
Interpreting Inverse Magnetic Fabric in Miocene Dikes From Eastern Iceland |
title_full |
Interpreting Inverse Magnetic Fabric in Miocene Dikes From Eastern Iceland |
title_fullStr |
Interpreting Inverse Magnetic Fabric in Miocene Dikes From Eastern Iceland |
title_full_unstemmed |
Interpreting Inverse Magnetic Fabric in Miocene Dikes From Eastern Iceland |
title_sort |
interpreting inverse magnetic fabric in miocene dikes from eastern iceland |
publisher |
HAL CCSD |
publishDate |
2020 |
url |
https://hal-insu.archives-ouvertes.fr/insu-03721893 https://hal-insu.archives-ouvertes.fr/insu-03721893/document https://hal-insu.archives-ouvertes.fr/insu-03721893/file/JGR%20Solid%20Earth%20-%202020%20-%20Trippanera%20-%20Interpreting%20Inverse%20Magnetic%20Fabric%20in%20Miocene%20Dikes%20From%20Eastern%20Iceland.pdf https://doi.org/10.1029/2020JB020306 |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
ISSN: 2169-9313 EISSN: 2169-9356 Journal of Geophysical Research : Solid Earth https://hal-insu.archives-ouvertes.fr/insu-03721893 Journal of Geophysical Research : Solid Earth, 2020, 125, ⟨10.1029/2020JB020306⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2020JB020306 insu-03721893 https://hal-insu.archives-ouvertes.fr/insu-03721893 https://hal-insu.archives-ouvertes.fr/insu-03721893/document https://hal-insu.archives-ouvertes.fr/insu-03721893/file/JGR%20Solid%20Earth%20-%202020%20-%20Trippanera%20-%20Interpreting%20Inverse%20Magnetic%20Fabric%20in%20Miocene%20Dikes%20From%20Eastern%20Iceland.pdf BIBCODE: 2020JGRB.12520306T doi:10.1029/2020JB020306 |
op_rights |
http://hal.archives-ouvertes.fr/licences/copyright/ info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2020JB020306 |
container_title |
Journal of Geophysical Research: Solid Earth |
container_volume |
125 |
container_issue |
11 |
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1768389654684368896 |