The Influence of Post‐accretion Sedimentation on Marine Magnetic Anomalies
International audience Marine magnetic anomalies are a critical observation used to investigate seafloor spreading and the transition between oceanic and continental crust at passive margins. However, pronounced post-accretion sedimentation disturbs the thermal state of the crust and therefore alter...
Published in: | Geophysical Research Letters |
---|---|
Main Authors: | , |
Other Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2019
|
Subjects: | |
Online Access: | https://hal.science/hal-02390143 https://hal.science/hal-02390143/document https://hal.science/hal-02390143/file/2019GL082265.pdf https://doi.org/10.1029/2019GL082265 |
id |
ftunivnantes:oai:HAL:hal-02390143v1 |
---|---|
record_format |
openpolar |
spelling |
ftunivnantes:oai:HAL:hal-02390143v1 2023-05-15T18:21:10+02:00 The Influence of Post‐accretion Sedimentation on Marine Magnetic Anomalies Granot, R. Dyment, J. Institut de Physique du Globe de Paris (IPGP) Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS) 2019-05-03 https://hal.science/hal-02390143 https://hal.science/hal-02390143/document https://hal.science/hal-02390143/file/2019GL082265.pdf https://doi.org/10.1029/2019GL082265 en eng HAL CCSD American Geophysical Union info:eu-repo/semantics/altIdentifier/doi/10.1029/2019GL082265 hal-02390143 https://hal.science/hal-02390143 https://hal.science/hal-02390143/document https://hal.science/hal-02390143/file/2019GL082265.pdf doi:10.1029/2019GL082265 info:eu-repo/semantics/OpenAccess ISSN: 0094-8276 EISSN: 1944-8007 Geophysical Research Letters https://hal.science/hal-02390143 Geophysical Research Letters, 2019, 46 (9), pp.4645-4652. ⟨10.1029/2019GL082265⟩ [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography info:eu-repo/semantics/article Journal articles 2019 ftunivnantes https://doi.org/10.1029/2019GL082265 2023-02-08T04:43:58Z International audience Marine magnetic anomalies are a critical observation used to investigate seafloor spreading and the transition between oceanic and continental crust at passive margins. However, pronounced post-accretion sedimentation disturbs the thermal state of the crust and therefore alters its remanent magnetization. To study the link between sedimentation and magnetization of the oceanic crust, we built a series of thermomagnetic forward models coupled with different sedimentation histories. We test our approach against observations from the early Cretaceous southern South Atlantic Ocean. Our simulations suggest that, depending on the thickness of post-accretion sediments, the remanent magnetization of the extrusive basalts is partly or completely removed. Therefore, the typical long-wavelength sea surface marine magnetic anomalies observed above oceanic crust covered by a thick sedimentary pile is almost entirely generated by the magnetization of the deeper crustal layers. Plain Language Summary Marine magnetic anomalies are a critical observation used to investigate seafloor spreading and the transition between oceanic and continental crust at passive margins. Here we show that the accumulation of sediments over the oceanic crust has a thermal effect, which can lead, under certain conditions, to the complete removal of magnetization in the upper oceanic crust. This, in turn, may have important consequences for how we understand passive margins and the accuracy of plate kinematic models. Article in Journal/Newspaper South Atlantic Ocean Université de Nantes: HAL-UNIV-NANTES Geophysical Research Letters 46 9 4645 4652 |
institution |
Open Polar |
collection |
Université de Nantes: HAL-UNIV-NANTES |
op_collection_id |
ftunivnantes |
language |
English |
topic |
[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
spellingShingle |
[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography Granot, R. Dyment, J. The Influence of Post‐accretion Sedimentation on Marine Magnetic Anomalies |
topic_facet |
[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
description |
International audience Marine magnetic anomalies are a critical observation used to investigate seafloor spreading and the transition between oceanic and continental crust at passive margins. However, pronounced post-accretion sedimentation disturbs the thermal state of the crust and therefore alters its remanent magnetization. To study the link between sedimentation and magnetization of the oceanic crust, we built a series of thermomagnetic forward models coupled with different sedimentation histories. We test our approach against observations from the early Cretaceous southern South Atlantic Ocean. Our simulations suggest that, depending on the thickness of post-accretion sediments, the remanent magnetization of the extrusive basalts is partly or completely removed. Therefore, the typical long-wavelength sea surface marine magnetic anomalies observed above oceanic crust covered by a thick sedimentary pile is almost entirely generated by the magnetization of the deeper crustal layers. Plain Language Summary Marine magnetic anomalies are a critical observation used to investigate seafloor spreading and the transition between oceanic and continental crust at passive margins. Here we show that the accumulation of sediments over the oceanic crust has a thermal effect, which can lead, under certain conditions, to the complete removal of magnetization in the upper oceanic crust. This, in turn, may have important consequences for how we understand passive margins and the accuracy of plate kinematic models. |
author2 |
Institut de Physique du Globe de Paris (IPGP) Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Granot, R. Dyment, J. |
author_facet |
Granot, R. Dyment, J. |
author_sort |
Granot, R. |
title |
The Influence of Post‐accretion Sedimentation on Marine Magnetic Anomalies |
title_short |
The Influence of Post‐accretion Sedimentation on Marine Magnetic Anomalies |
title_full |
The Influence of Post‐accretion Sedimentation on Marine Magnetic Anomalies |
title_fullStr |
The Influence of Post‐accretion Sedimentation on Marine Magnetic Anomalies |
title_full_unstemmed |
The Influence of Post‐accretion Sedimentation on Marine Magnetic Anomalies |
title_sort |
influence of post‐accretion sedimentation on marine magnetic anomalies |
publisher |
HAL CCSD |
publishDate |
2019 |
url |
https://hal.science/hal-02390143 https://hal.science/hal-02390143/document https://hal.science/hal-02390143/file/2019GL082265.pdf https://doi.org/10.1029/2019GL082265 |
genre |
South Atlantic Ocean |
genre_facet |
South Atlantic Ocean |
op_source |
ISSN: 0094-8276 EISSN: 1944-8007 Geophysical Research Letters https://hal.science/hal-02390143 Geophysical Research Letters, 2019, 46 (9), pp.4645-4652. ⟨10.1029/2019GL082265⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2019GL082265 hal-02390143 https://hal.science/hal-02390143 https://hal.science/hal-02390143/document https://hal.science/hal-02390143/file/2019GL082265.pdf doi:10.1029/2019GL082265 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2019GL082265 |
container_title |
Geophysical Research Letters |
container_volume |
46 |
container_issue |
9 |
container_start_page |
4645 |
op_container_end_page |
4652 |
_version_ |
1766200292276174848 |