Temporal variations of the segmentation of slow to intermediate spreading mid-ocean ridges 1. Synoptic observations based on satellite altimetry data
International audience The high-resolution geoid and gravity maps derived from ERS-1 and Geosat satellite geodetic missions reveal a set of small-scale lineations on the flanks of slow to intermediate spreading mid- ocean ridges. Assuming that these lineations reflect the variations in crustal struc...
Published in: | Journal of Geophysical Research |
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Main Authors: | , |
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Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2002
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Online Access: | https://hal.science/hal-00552201 https://hal.science/hal-00552201/document https://hal.science/hal-00552201/file/Briais_Rabinowicz_JGR02_MOR_segmentation.pdf https://doi.org/10.1029/2001JB000533 |
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ftunivnantes:oai:HAL:hal-00552201v1 |
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openpolar |
institution |
Open Polar |
collection |
Université de Nantes: HAL-UNIV-NANTES |
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ftunivnantes |
language |
English |
topic |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences Briais, Anne Rabinowicz, Michel Temporal variations of the segmentation of slow to intermediate spreading mid-ocean ridges 1. Synoptic observations based on satellite altimetry data |
topic_facet |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience The high-resolution geoid and gravity maps derived from ERS-1 and Geosat satellite geodetic missions reveal a set of small-scale lineations on the flanks of slow to intermediate spreading mid- ocean ridges. Assuming that these lineations reflect the variations in crustal structure induced by mid-ocean ridge axial discontinuities, we use them to investigate how the discontinuities, and the segments they bound, appear, migrate, and disappear. We provide a synoptic description of the main characteristics of the crustal structure variations, as well as their evolution in time, over the flanks of the Mid-Atlantic, Indian, and Pacific-Antarctic Ridges. The second-order segment length does not appear to vary with the spreading rate for the slow to intermediate spreading ridges investigated here. The amplitude of the gravity signal associated with off-axis discontinuity traces increases with the obliquity of the ridge to spreading and decreases with spreading rate and with the proximity of a ridge section to a hot spot. The patterns of the gravity lineations appear to be very homogeneous over 500- to 1000-km-large corridors bounded by large fracture zones. Far from hot spots, corridors are characterized either by segments bounded by discontinuities migrating back and forth along the axis, implying a lifetime of 10–30 Myr for the segments, or by segments and discontinuities very stable in space and time, surviving for 40–50 Myr. Closer to hot spots, the segmentation is affected in two ways. First, segments tend to migrate along axis away from hot spots, or toward cold spots. Second, asymmetric spreading tends to keep sections of ridges closer to hot spots than normal spreading would. These observations support the hypothesis that ridge segmentation and its evolution are controlled by mantle dynamics. Our analysis provides observational constraints for further models of crustal production along ridges, which are presented in the companion paper by Rabinowicz and Briais [2002]. |
author2 |
Dynamique terrestre et planétaire (DTP) Université Toulouse III - Paul Sabatier (UT3) Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-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 Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-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)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Briais, Anne Rabinowicz, Michel |
author_facet |
Briais, Anne Rabinowicz, Michel |
author_sort |
Briais, Anne |
title |
Temporal variations of the segmentation of slow to intermediate spreading mid-ocean ridges 1. Synoptic observations based on satellite altimetry data |
title_short |
Temporal variations of the segmentation of slow to intermediate spreading mid-ocean ridges 1. Synoptic observations based on satellite altimetry data |
title_full |
Temporal variations of the segmentation of slow to intermediate spreading mid-ocean ridges 1. Synoptic observations based on satellite altimetry data |
title_fullStr |
Temporal variations of the segmentation of slow to intermediate spreading mid-ocean ridges 1. Synoptic observations based on satellite altimetry data |
title_full_unstemmed |
Temporal variations of the segmentation of slow to intermediate spreading mid-ocean ridges 1. Synoptic observations based on satellite altimetry data |
title_sort |
temporal variations of the segmentation of slow to intermediate spreading mid-ocean ridges 1. synoptic observations based on satellite altimetry data |
publisher |
HAL CCSD |
publishDate |
2002 |
url |
https://hal.science/hal-00552201 https://hal.science/hal-00552201/document https://hal.science/hal-00552201/file/Briais_Rabinowicz_JGR02_MOR_segmentation.pdf https://doi.org/10.1029/2001JB000533 |
geographic |
Antarctic Pacific Indian |
geographic_facet |
Antarctic Pacific Indian |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
ISSN: 2169-9313 EISSN: 2169-9356 Journal of Geophysical Research : Solid Earth https://hal.science/hal-00552201 Journal of Geophysical Research : Solid Earth, 2002, pp.VOL. 107, NO. B5, 2098. ⟨10.1029/2001JB000533⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2001JB000533 hal-00552201 https://hal.science/hal-00552201 https://hal.science/hal-00552201/document https://hal.science/hal-00552201/file/Briais_Rabinowicz_JGR02_MOR_segmentation.pdf doi:10.1029/2001JB000533 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2001JB000533 |
container_title |
Journal of Geophysical Research |
container_volume |
107 |
container_issue |
B5 |
_version_ |
1766168047661350912 |
spelling |
ftunivnantes:oai:HAL:hal-00552201v1 2023-05-15T13:42:27+02:00 Temporal variations of the segmentation of slow to intermediate spreading mid-ocean ridges 1. Synoptic observations based on satellite altimetry data Briais, Anne Rabinowicz, Michel Dynamique terrestre et planétaire (DTP) Université Toulouse III - Paul Sabatier (UT3) Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-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 Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-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)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS) 2002-05-25 https://hal.science/hal-00552201 https://hal.science/hal-00552201/document https://hal.science/hal-00552201/file/Briais_Rabinowicz_JGR02_MOR_segmentation.pdf https://doi.org/10.1029/2001JB000533 en eng HAL CCSD American Geophysical Union info:eu-repo/semantics/altIdentifier/doi/10.1029/2001JB000533 hal-00552201 https://hal.science/hal-00552201 https://hal.science/hal-00552201/document https://hal.science/hal-00552201/file/Briais_Rabinowicz_JGR02_MOR_segmentation.pdf doi:10.1029/2001JB000533 info:eu-repo/semantics/OpenAccess ISSN: 2169-9313 EISSN: 2169-9356 Journal of Geophysical Research : Solid Earth https://hal.science/hal-00552201 Journal of Geophysical Research : Solid Earth, 2002, pp.VOL. 107, NO. B5, 2098. ⟨10.1029/2001JB000533⟩ [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2002 ftunivnantes https://doi.org/10.1029/2001JB000533 2023-02-22T00:23:11Z International audience The high-resolution geoid and gravity maps derived from ERS-1 and Geosat satellite geodetic missions reveal a set of small-scale lineations on the flanks of slow to intermediate spreading mid- ocean ridges. Assuming that these lineations reflect the variations in crustal structure induced by mid-ocean ridge axial discontinuities, we use them to investigate how the discontinuities, and the segments they bound, appear, migrate, and disappear. We provide a synoptic description of the main characteristics of the crustal structure variations, as well as their evolution in time, over the flanks of the Mid-Atlantic, Indian, and Pacific-Antarctic Ridges. The second-order segment length does not appear to vary with the spreading rate for the slow to intermediate spreading ridges investigated here. The amplitude of the gravity signal associated with off-axis discontinuity traces increases with the obliquity of the ridge to spreading and decreases with spreading rate and with the proximity of a ridge section to a hot spot. The patterns of the gravity lineations appear to be very homogeneous over 500- to 1000-km-large corridors bounded by large fracture zones. Far from hot spots, corridors are characterized either by segments bounded by discontinuities migrating back and forth along the axis, implying a lifetime of 10–30 Myr for the segments, or by segments and discontinuities very stable in space and time, surviving for 40–50 Myr. Closer to hot spots, the segmentation is affected in two ways. First, segments tend to migrate along axis away from hot spots, or toward cold spots. Second, asymmetric spreading tends to keep sections of ridges closer to hot spots than normal spreading would. These observations support the hypothesis that ridge segmentation and its evolution are controlled by mantle dynamics. Our analysis provides observational constraints for further models of crustal production along ridges, which are presented in the companion paper by Rabinowicz and Briais [2002]. Article in Journal/Newspaper Antarc* Antarctic Université de Nantes: HAL-UNIV-NANTES Antarctic Pacific Indian Journal of Geophysical Research 107 B5 |