Origin of volcanism on the flanks of the Pacific-Antarctic ridge between 41°30'S and 52°S
20 pages; 12142 words; 6 figures; 3 tables International audience Non-hotspot, intraplate volcanism is a common feature near the East Pacific Rise or Pacific-Antarctic Ridge. Volcanic ridges and seamount chains, tens to hundreds of kilometers long, are asymmetrically distributed about the ridge axis...
Published in: | Geochemistry, Geophysics, Geosystems |
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Main Authors: | , , , , , |
Other Authors: | , , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2009
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Subjects: | |
Online Access: | https://hal.science/hal-00543807 https://hal.science/hal-00543807/document https://hal.science/hal-00543807/file/Briais_G3_09_Pacant2_offaxis_volcanoes.pdf https://doi.org/10.1029/2008GC002350 |
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Open Polar |
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Institut national des sciences de l'Univers: HAL-INSU |
op_collection_id |
ftinsu |
language |
English |
topic |
Mid-ocean ridges Off-axis volcanism Mantle convection Plate kinematics Transform fault [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
Mid-ocean ridges Off-axis volcanism Mantle convection Plate kinematics Transform fault [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Briais, Anne Ondréas, Hélène Klingelhoefer, Frauke Dosso, Laure Hamelin, Cédric Guillou, Hervé Origin of volcanism on the flanks of the Pacific-Antarctic ridge between 41°30'S and 52°S |
topic_facet |
Mid-ocean ridges Off-axis volcanism Mantle convection Plate kinematics Transform fault [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
20 pages; 12142 words; 6 figures; 3 tables International audience Non-hotspot, intraplate volcanism is a common feature near the East Pacific Rise or Pacific-Antarctic Ridge. Volcanic ridges and seamount chains, tens to hundreds of kilometers long, are asymmetrically distributed about the ridge axis, most volcanic features occurring on the Pacific plate. Their origins remain controversial. We have analyzed off-axis volcanic ridges near the Pacific-Antarctic ridge from bathymetry, backscatter, gravity and geochemistry data of the Pacantarctic2 cruise. K/Ar dating of samples dredged on these structures reveal a contrast of up to 3 Ma between the volcanoes and the underlying crust. The volcanic activity, as suggested by the strong backscatter in sonar images, appears to be limited to areas of seafloor younger than about 3 Ma. All surveyed ridges north of the Menard transform fault (TF) show recent activity close to the ridge axis, and are not affected by faults. The off-axis volcanic ridges south of the Menard TF show recent volcanic flows in their center, and are affected by N-S extension. Two different types of volcanoes can be characterized: conical, flat-topped ones and rough, elongated ones associated with narrow, EW-trending volcanic ridges, some of them showing strong backscattering on the EM12 imagery. From the morphology of the seamount chains and the ages of the lava samples, we infer that the magma source for the volcanic ridges is related to the feeding of the ridge axis through three-dimensional mantle convective circulation. We suggest that a change in the relative plate motion since about 5 Ma might have induced an offset of the mantle upwelling circulation under the ridge axis so that anomalously hot mantle rises under the Pacific ridge flank. The kinematic change is also likely responsible for the tectonic deformation in the young lithosphere south of Menard TF. |
author2 |
Dynamique terrestre et planétaire (DTP) Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) Géosciences Marines (GM) Domaines Océaniques (LDO) Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS) Université de Brest (UBO) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) Paléocéanographie (PALEOCEAN) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) |
format |
Article in Journal/Newspaper |
author |
Briais, Anne Ondréas, Hélène Klingelhoefer, Frauke Dosso, Laure Hamelin, Cédric Guillou, Hervé |
author_facet |
Briais, Anne Ondréas, Hélène Klingelhoefer, Frauke Dosso, Laure Hamelin, Cédric Guillou, Hervé |
author_sort |
Briais, Anne |
title |
Origin of volcanism on the flanks of the Pacific-Antarctic ridge between 41°30'S and 52°S |
title_short |
Origin of volcanism on the flanks of the Pacific-Antarctic ridge between 41°30'S and 52°S |
title_full |
Origin of volcanism on the flanks of the Pacific-Antarctic ridge between 41°30'S and 52°S |
title_fullStr |
Origin of volcanism on the flanks of the Pacific-Antarctic ridge between 41°30'S and 52°S |
title_full_unstemmed |
Origin of volcanism on the flanks of the Pacific-Antarctic ridge between 41°30'S and 52°S |
title_sort |
origin of volcanism on the flanks of the pacific-antarctic ridge between 41°30's and 52°s |
publisher |
HAL CCSD |
publishDate |
2009 |
url |
https://hal.science/hal-00543807 https://hal.science/hal-00543807/document https://hal.science/hal-00543807/file/Briais_G3_09_Pacant2_offaxis_volcanoes.pdf https://doi.org/10.1029/2008GC002350 |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
ISSN: 1525-2027 EISSN: 1525-2027 Geochemistry, Geophysics, Geosystems https://hal.science/hal-00543807 Geochemistry, Geophysics, Geosystems, 2009, 10 (9), pp.Q09001. ⟨10.1029/2008GC002350⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2008GC002350 hal-00543807 https://hal.science/hal-00543807 https://hal.science/hal-00543807/document https://hal.science/hal-00543807/file/Briais_G3_09_Pacant2_offaxis_volcanoes.pdf doi:10.1029/2008GC002350 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2008GC002350 |
container_title |
Geochemistry, Geophysics, Geosystems |
container_volume |
10 |
container_issue |
9 |
container_start_page |
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op_container_end_page |
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1797572899083649024 |
spelling |
ftinsu:oai:HAL:hal-00543807v1 2024-04-28T08:00:52+00:00 Origin of volcanism on the flanks of the Pacific-Antarctic ridge between 41°30'S and 52°S Briais, Anne Ondréas, Hélène Klingelhoefer, Frauke Dosso, Laure Hamelin, Cédric Guillou, Hervé Dynamique terrestre et planétaire (DTP) Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) Géosciences Marines (GM) Domaines Océaniques (LDO) Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS) Université de Brest (UBO) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) Paléocéanographie (PALEOCEAN) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) 2009-09-01 https://hal.science/hal-00543807 https://hal.science/hal-00543807/document https://hal.science/hal-00543807/file/Briais_G3_09_Pacant2_offaxis_volcanoes.pdf https://doi.org/10.1029/2008GC002350 en eng HAL CCSD AGU and the Geochemical Society info:eu-repo/semantics/altIdentifier/doi/10.1029/2008GC002350 hal-00543807 https://hal.science/hal-00543807 https://hal.science/hal-00543807/document https://hal.science/hal-00543807/file/Briais_G3_09_Pacant2_offaxis_volcanoes.pdf doi:10.1029/2008GC002350 info:eu-repo/semantics/OpenAccess ISSN: 1525-2027 EISSN: 1525-2027 Geochemistry, Geophysics, Geosystems https://hal.science/hal-00543807 Geochemistry, Geophysics, Geosystems, 2009, 10 (9), pp.Q09001. ⟨10.1029/2008GC002350⟩ Mid-ocean ridges Off-axis volcanism Mantle convection Plate kinematics Transform fault [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2009 ftinsu https://doi.org/10.1029/2008GC002350 2024-04-05T00:25:18Z 20 pages; 12142 words; 6 figures; 3 tables International audience Non-hotspot, intraplate volcanism is a common feature near the East Pacific Rise or Pacific-Antarctic Ridge. Volcanic ridges and seamount chains, tens to hundreds of kilometers long, are asymmetrically distributed about the ridge axis, most volcanic features occurring on the Pacific plate. Their origins remain controversial. We have analyzed off-axis volcanic ridges near the Pacific-Antarctic ridge from bathymetry, backscatter, gravity and geochemistry data of the Pacantarctic2 cruise. K/Ar dating of samples dredged on these structures reveal a contrast of up to 3 Ma between the volcanoes and the underlying crust. The volcanic activity, as suggested by the strong backscatter in sonar images, appears to be limited to areas of seafloor younger than about 3 Ma. All surveyed ridges north of the Menard transform fault (TF) show recent activity close to the ridge axis, and are not affected by faults. The off-axis volcanic ridges south of the Menard TF show recent volcanic flows in their center, and are affected by N-S extension. Two different types of volcanoes can be characterized: conical, flat-topped ones and rough, elongated ones associated with narrow, EW-trending volcanic ridges, some of them showing strong backscattering on the EM12 imagery. From the morphology of the seamount chains and the ages of the lava samples, we infer that the magma source for the volcanic ridges is related to the feeding of the ridge axis through three-dimensional mantle convective circulation. We suggest that a change in the relative plate motion since about 5 Ma might have induced an offset of the mantle upwelling circulation under the ridge axis so that anomalously hot mantle rises under the Pacific ridge flank. The kinematic change is also likely responsible for the tectonic deformation in the young lithosphere south of Menard TF. Article in Journal/Newspaper Antarc* Antarctic Institut national des sciences de l'Univers: HAL-INSU Geochemistry, Geophysics, Geosystems 10 9 n/a n/a |