The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day
The Iceland hotspot has profoundly influenced the creation of oceanic crust throughout the North Atlantic basin. Enigmatically, the geographic extent of the hotspot influence along the Mid-Atlantic Ridge has been asymmetric for most of the spreading history. This asymmetry is evident in crustal thic...
Published in: | Earth and Planetary Science Letters |
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Format: | Article in Journal/Newspaper |
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EARTH AND PLANETARY SCIENCE LETTERS
2014
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Online Access: | https://hdl.handle.net/11511/36012 https://doi.org/10.1016/j.epsl.2014.02.020 |
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ftmetuankair:oai:open.metu.edu.tr:11511/36012 2023-05-15T16:48:19+02:00 The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day Howell, Samuel M. Ito, Garrett Breivik, Asbjorn J. Rai, Abhishek Mjelde, Rolf Hanan, Barry Sayıt, Kaan Vogt, Peter 2014-04-15 application/pdf https://hdl.handle.net/11511/36012 https://doi.org/10.1016/j.epsl.2014.02.020 unknown EARTH AND PLANETARY SCIENCE LETTERS Howell S. M. , Ito G., Breivik A. J. , Rai A., Mjelde R., Hanan B., Sayit K., Vogt P., "The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day", EARTH AND PLANETARY SCIENCE LETTERS, cilt.392, ss.143-153, 2014 doi:10.1016/j.epsl.2014.02.020 153 0012-821X 84896821006 143 https://hdl.handle.net/11511/36012 392 WOS:000349141100016 Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ CC-BY-NC-ND North Atlantic Mantle plumes Mid-ocean ridges Continental rifting Hotspots Dehydration Journal Article 2014 ftmetuankair https://doi.org/10.1016/j.epsl.2014.02.020 2020-10-28T15:23:32Z The Iceland hotspot has profoundly influenced the creation of oceanic crust throughout the North Atlantic basin. Enigmatically, the geographic extent of the hotspot influence along the Mid-Atlantic Ridge has been asymmetric for most of the spreading history. This asymmetry is evident in crustal thickness along the present-day ridge system and anomalously shallow seafloor of ages similar to 49-25 Ma created at the Reykjanes Ridge (RR), SSW of the hotspot center, compared to deeper seafloor created by the now-extinct Aegir Ridge (AR) the same distance NE of the hotspot center. The cause of this asymmetry is explored with 3-D numerical models that simulate a mantle plume interacting with the ridge system using realistic ridge geometries and spreading rates that evolve from continental breakup to present-day. The models predict plume-influence to be symmetric at continental breakup, then to rapidly contract along the ridges, resulting in widely influenced margins next to uninfluenced oceanic crust. After this initial stage, varying degrees of asymmetry along the mature ridge segments are predicted. Models in which the lithosphere is created by the stiffening of the mantle due to the extraction of water near the base of the melting zone predict a moderate amount of asymmetry; the plume expands NE along the AR similar to 70-80% as far as it expands SSW along the RR. Without dehydration stiffening, the lithosphere corresponds to the near-surface, cool, thermal boundary layer; in these cases, the plume is predicted to be even more asymmetric, expanding only 40-50% as far along the AR as it does along the RR. Estimates of asymmetry and seismically measured crustal thicknesses are best explained by model predictions of an Iceland plume volume flux of similar to 100-200 m(3)/s, and a lithosphere controlled by a rheology in which dehydration stiffens the mantle, but to a lesser degree than simulated here. The asymmetry of influence along the present-day ridge system is predicted to be a transient configuration in which plume influence along the Reykjanes Ridge is steady, but is still widening along the Kolbeinsey Ridge, as it has been since this ridge formed at similar to 25 Ma. (C) 2014 Elsevier B.V. All rights reserved. Article in Journal/Newspaper Iceland Kolbeinsey North Atlantic OpenMETU (Middle East Technical University) Aegir Ridge ENVELOPE(-4.125,-4.125,66.167,66.167) Kolbeinsey ENVELOPE(-18.687,-18.687,67.149,67.149) Kolbeinsey Ridge ENVELOPE(-16.917,-16.917,68.833,68.833) Mid-Atlantic Ridge Reykjanes ENVELOPE(-22.250,-22.250,65.467,65.467) Earth and Planetary Science Letters 392 143 153 |
institution |
Open Polar |
collection |
OpenMETU (Middle East Technical University) |
op_collection_id |
ftmetuankair |
language |
unknown |
topic |
North Atlantic Mantle plumes Mid-ocean ridges Continental rifting Hotspots Dehydration |
spellingShingle |
North Atlantic Mantle plumes Mid-ocean ridges Continental rifting Hotspots Dehydration Howell, Samuel M. Ito, Garrett Breivik, Asbjorn J. Rai, Abhishek Mjelde, Rolf Hanan, Barry Sayıt, Kaan Vogt, Peter The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day |
topic_facet |
North Atlantic Mantle plumes Mid-ocean ridges Continental rifting Hotspots Dehydration |
description |
The Iceland hotspot has profoundly influenced the creation of oceanic crust throughout the North Atlantic basin. Enigmatically, the geographic extent of the hotspot influence along the Mid-Atlantic Ridge has been asymmetric for most of the spreading history. This asymmetry is evident in crustal thickness along the present-day ridge system and anomalously shallow seafloor of ages similar to 49-25 Ma created at the Reykjanes Ridge (RR), SSW of the hotspot center, compared to deeper seafloor created by the now-extinct Aegir Ridge (AR) the same distance NE of the hotspot center. The cause of this asymmetry is explored with 3-D numerical models that simulate a mantle plume interacting with the ridge system using realistic ridge geometries and spreading rates that evolve from continental breakup to present-day. The models predict plume-influence to be symmetric at continental breakup, then to rapidly contract along the ridges, resulting in widely influenced margins next to uninfluenced oceanic crust. After this initial stage, varying degrees of asymmetry along the mature ridge segments are predicted. Models in which the lithosphere is created by the stiffening of the mantle due to the extraction of water near the base of the melting zone predict a moderate amount of asymmetry; the plume expands NE along the AR similar to 70-80% as far as it expands SSW along the RR. Without dehydration stiffening, the lithosphere corresponds to the near-surface, cool, thermal boundary layer; in these cases, the plume is predicted to be even more asymmetric, expanding only 40-50% as far along the AR as it does along the RR. Estimates of asymmetry and seismically measured crustal thicknesses are best explained by model predictions of an Iceland plume volume flux of similar to 100-200 m(3)/s, and a lithosphere controlled by a rheology in which dehydration stiffens the mantle, but to a lesser degree than simulated here. The asymmetry of influence along the present-day ridge system is predicted to be a transient configuration in which plume influence along the Reykjanes Ridge is steady, but is still widening along the Kolbeinsey Ridge, as it has been since this ridge formed at similar to 25 Ma. (C) 2014 Elsevier B.V. All rights reserved. |
format |
Article in Journal/Newspaper |
author |
Howell, Samuel M. Ito, Garrett Breivik, Asbjorn J. Rai, Abhishek Mjelde, Rolf Hanan, Barry Sayıt, Kaan Vogt, Peter |
author_facet |
Howell, Samuel M. Ito, Garrett Breivik, Asbjorn J. Rai, Abhishek Mjelde, Rolf Hanan, Barry Sayıt, Kaan Vogt, Peter |
author_sort |
Howell, Samuel M. |
title |
The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day |
title_short |
The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day |
title_full |
The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day |
title_fullStr |
The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day |
title_full_unstemmed |
The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day |
title_sort |
origin of the asymmetry in the iceland hotspot along the mid-atlantic ridge from continental breakup to present-day |
publisher |
EARTH AND PLANETARY SCIENCE LETTERS |
publishDate |
2014 |
url |
https://hdl.handle.net/11511/36012 https://doi.org/10.1016/j.epsl.2014.02.020 |
long_lat |
ENVELOPE(-4.125,-4.125,66.167,66.167) ENVELOPE(-18.687,-18.687,67.149,67.149) ENVELOPE(-16.917,-16.917,68.833,68.833) ENVELOPE(-22.250,-22.250,65.467,65.467) |
geographic |
Aegir Ridge Kolbeinsey Kolbeinsey Ridge Mid-Atlantic Ridge Reykjanes |
geographic_facet |
Aegir Ridge Kolbeinsey Kolbeinsey Ridge Mid-Atlantic Ridge Reykjanes |
genre |
Iceland Kolbeinsey North Atlantic |
genre_facet |
Iceland Kolbeinsey North Atlantic |
op_relation |
Howell S. M. , Ito G., Breivik A. J. , Rai A., Mjelde R., Hanan B., Sayit K., Vogt P., "The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day", EARTH AND PLANETARY SCIENCE LETTERS, cilt.392, ss.143-153, 2014 doi:10.1016/j.epsl.2014.02.020 153 0012-821X 84896821006 143 https://hdl.handle.net/11511/36012 392 WOS:000349141100016 |
op_rights |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ |
op_rightsnorm |
CC-BY-NC-ND |
op_doi |
https://doi.org/10.1016/j.epsl.2014.02.020 |
container_title |
Earth and Planetary Science Letters |
container_volume |
392 |
container_start_page |
143 |
op_container_end_page |
153 |
_version_ |
1766038414020313088 |