Geodynamics of rift-plume interaction in Iceland as constrained by new 40Ar/39Ar and in situ U-Pb zircon ages
International audience The interaction between a rift zone and a mantle plume leads to exceptional situations in Iceland where the island is 1.5 wider than expected, given the North-Atlantic spreading rate. In order to give a better idea of the timeframe of this evolution, we present 32 new 40Ar/39A...
Published in: | Earth and Planetary Science Letters |
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Main Authors: | , , , , , |
Other Authors: | , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2011
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Subjects: | |
Online Access: | https://hal.science/hal-00635403 https://doi.org/10.1016/j.epsl.2011.08.036 |
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ftunivrennes1hal:oai:HAL:hal-00635403v1 |
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openpolar |
institution |
Open Polar |
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Université de Rennes 1: Publications scientifiques (HAL) |
op_collection_id |
ftunivrennes1hal |
language |
English |
topic |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences Martin, Erwan Paquette, Jean-Louis Bosse, Valérie Ruffet, G. Tiepolo, M. Sigmarsson, Olgeir Geodynamics of rift-plume interaction in Iceland as constrained by new 40Ar/39Ar and in situ U-Pb zircon ages |
topic_facet |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience The interaction between a rift zone and a mantle plume leads to exceptional situations in Iceland where the island is 1.5 wider than expected, given the North-Atlantic spreading rate. In order to give a better idea of the timeframe of this evolution, we present 32 new 40Ar/39Ar and in-situ U-Pb dating on zircon from 16 volcanic systems located from the west to east coasts of Iceland. The North Iceland Rift Zone (NIRZ) was initiated at least 12 Ma ago. Furthermore, during these last 12 Ma, the NIRZ half spreading rate was between 0.7 and 1.2 cm/yr and it propagated to the south at a rate of 1.0-1.2 cm/yr. The excess width of Iceland can thus not be explained by faster spreading rate in the past. Here we discuss a model that explains the ~200 km 'excess' of crust, taking into account the eastward relocation of the rift zone and corresponding older crustal capture over the course of Iceland's geological history. The most recent rift relocation is dated at approxi- mately 6 Ma at Snæfellsnes Peninsula in the west, whereas the oldest volcanic systems (15-13 Ma) from the extreme north east of Iceland were most likely generated at the Kolbeinsey ridge north of Iceland rather than in the NIRZ itself. The need for rift relocations and crustal capture to explain the width of Iceland strongly suggests that during rift-plume interaction the mantle plume plays an active role. It forces the active rift zone to be frequently relocated by rift jumps above its center leaving inactive rift zones as older synclines in the geological record. This result in an eastward position of the rift zone in Iceland relative to the North Atlantic ridge, and it can be predicted that in a few tens of millions of years the Mid-Atlantic ridge and the Icelandic plume may become decoupled. |
author2 |
Laboratoire Magmas et Volcans (LMV) Observatoire de Physique du Globe de Clermont-Ferrand (OPGC) Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS) Institut des Sciences de la Terre de Paris (iSTeP) Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS) Terre, Temps, Traçage Géosciences Rennes (GR) Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS) CNR Istituto di Geoscienze e Georisorse Pavia (IGG) Consiglio Nazionale delle Ricerche (CNR) Institute of Earth Sciences Reykjavik University of Iceland Reykjavik |
format |
Article in Journal/Newspaper |
author |
Martin, Erwan Paquette, Jean-Louis Bosse, Valérie Ruffet, G. Tiepolo, M. Sigmarsson, Olgeir |
author_facet |
Martin, Erwan Paquette, Jean-Louis Bosse, Valérie Ruffet, G. Tiepolo, M. Sigmarsson, Olgeir |
author_sort |
Martin, Erwan |
title |
Geodynamics of rift-plume interaction in Iceland as constrained by new 40Ar/39Ar and in situ U-Pb zircon ages |
title_short |
Geodynamics of rift-plume interaction in Iceland as constrained by new 40Ar/39Ar and in situ U-Pb zircon ages |
title_full |
Geodynamics of rift-plume interaction in Iceland as constrained by new 40Ar/39Ar and in situ U-Pb zircon ages |
title_fullStr |
Geodynamics of rift-plume interaction in Iceland as constrained by new 40Ar/39Ar and in situ U-Pb zircon ages |
title_full_unstemmed |
Geodynamics of rift-plume interaction in Iceland as constrained by new 40Ar/39Ar and in situ U-Pb zircon ages |
title_sort |
geodynamics of rift-plume interaction in iceland as constrained by new 40ar/39ar and in situ u-pb zircon ages |
publisher |
HAL CCSD |
publishDate |
2011 |
url |
https://hal.science/hal-00635403 https://doi.org/10.1016/j.epsl.2011.08.036 |
long_lat |
ENVELOPE(-18.687,-18.687,67.149,67.149) ENVELOPE(-16.917,-16.917,68.833,68.833) |
geographic |
Mid-Atlantic Ridge Kolbeinsey Kolbeinsey Ridge |
geographic_facet |
Mid-Atlantic Ridge Kolbeinsey Kolbeinsey Ridge |
genre |
Iceland Kolbeinsey North Atlantic |
genre_facet |
Iceland Kolbeinsey North Atlantic |
op_source |
ISSN: 0012-821X Earth and Planetary Science Letters https://hal.science/hal-00635403 Earth and Planetary Science Letters, 2011, 311, pp.28-38. ⟨10.1016/j.epsl.2011.08.036⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.epsl.2011.08.036 hal-00635403 https://hal.science/hal-00635403 doi:10.1016/j.epsl.2011.08.036 |
op_doi |
https://doi.org/10.1016/j.epsl.2011.08.036 |
container_title |
Earth and Planetary Science Letters |
container_volume |
311 |
container_issue |
1-2 |
container_start_page |
28 |
op_container_end_page |
38 |
_version_ |
1766033947973648384 |
spelling |
ftunivrennes1hal:oai:HAL:hal-00635403v1 2023-05-15T16:43:37+02:00 Geodynamics of rift-plume interaction in Iceland as constrained by new 40Ar/39Ar and in situ U-Pb zircon ages Martin, Erwan Paquette, Jean-Louis Bosse, Valérie Ruffet, G. Tiepolo, M. Sigmarsson, Olgeir Laboratoire Magmas et Volcans (LMV) Observatoire de Physique du Globe de Clermont-Ferrand (OPGC) Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS) Institut des Sciences de la Terre de Paris (iSTeP) Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS) Terre, Temps, Traçage Géosciences Rennes (GR) Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS) CNR Istituto di Geoscienze e Georisorse Pavia (IGG) Consiglio Nazionale delle Ricerche (CNR) Institute of Earth Sciences Reykjavik University of Iceland Reykjavik 2011 https://hal.science/hal-00635403 https://doi.org/10.1016/j.epsl.2011.08.036 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.epsl.2011.08.036 hal-00635403 https://hal.science/hal-00635403 doi:10.1016/j.epsl.2011.08.036 ISSN: 0012-821X Earth and Planetary Science Letters https://hal.science/hal-00635403 Earth and Planetary Science Letters, 2011, 311, pp.28-38. ⟨10.1016/j.epsl.2011.08.036⟩ [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2011 ftunivrennes1hal https://doi.org/10.1016/j.epsl.2011.08.036 2023-04-11T22:45:15Z International audience The interaction between a rift zone and a mantle plume leads to exceptional situations in Iceland where the island is 1.5 wider than expected, given the North-Atlantic spreading rate. In order to give a better idea of the timeframe of this evolution, we present 32 new 40Ar/39Ar and in-situ U-Pb dating on zircon from 16 volcanic systems located from the west to east coasts of Iceland. The North Iceland Rift Zone (NIRZ) was initiated at least 12 Ma ago. Furthermore, during these last 12 Ma, the NIRZ half spreading rate was between 0.7 and 1.2 cm/yr and it propagated to the south at a rate of 1.0-1.2 cm/yr. The excess width of Iceland can thus not be explained by faster spreading rate in the past. Here we discuss a model that explains the ~200 km 'excess' of crust, taking into account the eastward relocation of the rift zone and corresponding older crustal capture over the course of Iceland's geological history. The most recent rift relocation is dated at approxi- mately 6 Ma at Snæfellsnes Peninsula in the west, whereas the oldest volcanic systems (15-13 Ma) from the extreme north east of Iceland were most likely generated at the Kolbeinsey ridge north of Iceland rather than in the NIRZ itself. The need for rift relocations and crustal capture to explain the width of Iceland strongly suggests that during rift-plume interaction the mantle plume plays an active role. It forces the active rift zone to be frequently relocated by rift jumps above its center leaving inactive rift zones as older synclines in the geological record. This result in an eastward position of the rift zone in Iceland relative to the North Atlantic ridge, and it can be predicted that in a few tens of millions of years the Mid-Atlantic ridge and the Icelandic plume may become decoupled. Article in Journal/Newspaper Iceland Kolbeinsey North Atlantic Université de Rennes 1: Publications scientifiques (HAL) Mid-Atlantic Ridge Kolbeinsey ENVELOPE(-18.687,-18.687,67.149,67.149) Kolbeinsey Ridge ENVELOPE(-16.917,-16.917,68.833,68.833) Earth and Planetary Science Letters 311 1-2 28 38 |