Magmatism at Passive Margins: Effects of Depth-Dependent Wide Rifting and Lithospheric Counterflow
Rifted passive margins exhibit a large variety in the timing, distribution, and amount of magmatism. The factors controlling magmatism during rifted margin formation, remain, however, incompletely understood, partly owing to the complex rifting styles. In this study, we use 2-Dimensional numerical m...
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Online Access: | https://hdl.handle.net/11250/3055619 https://doi.org/10.1029/2021JB023046 |
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ftunivbergen:oai:bora.uib.no:11250/3055619 2023-05-15T17:08:18+02:00 Magmatism at Passive Margins: Effects of Depth-Dependent Wide Rifting and Lithospheric Counterflow Lu, Gang Huismans, Ritske Sipke 2022 application/pdf https://hdl.handle.net/11250/3055619 https://doi.org/10.1029/2021JB023046 eng eng Wiley Sigma2: NN4704K Sigma2: NS4704K urn:issn:2169-9313 https://hdl.handle.net/11250/3055619 https://doi.org/10.1029/2021JB023046 cristin:2020401 Journal of Geophysical Research: Solid Earth. 2022, 127 (3), e2021JB023046. Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright 2022 The Authors e2021JB023046 Journal of Geophysical Research (JGR): Solid Earth 127 3 Journal article Peer reviewed 2022 ftunivbergen https://doi.org/10.1029/2021JB023046 2023-03-14T17:38:45Z Rifted passive margins exhibit a large variety in the timing, distribution, and amount of magmatism. The factors controlling magmatism during rifted margin formation, remain, however, incompletely understood, partly owing to the complex rifting styles. In this study, we use 2-Dimensional numerical models to investigate the effects of depth-dependent wide rifting and lithospheric counterflow on magmatism during rifted margin formation. Results show that a strong crust promotes narrow margins with a sharp transition to normal thickness oceanic crust whereas a weak crust promotes depth-dependent wide rifting, with preferential removal of mantle lithosphere, leading to formation of wide margins with over-thickened (>18 km) igneous crust in the distal margin. Counterflow of depleted lithospheric mantle, in contrast, may delay syn-rift magmatism, and result in exhumed a-magmatic continental mantle at narrow margins. The combination of wide rifting and lithospheric counterflow results in magma-poor wide margins, with in some cases a transition to excess magmatic activity at breakup. Our models provide an explanation for the contrasting magmatic productivity at narrow and wide rifted margins, such as observed in the Lofoten-Vesterålen, Newfoundland, Kwanza Basin, and Orange Basin margins. publishedVersion Article in Journal/Newspaper Lofoten Newfoundland Vesterålen University of Bergen: Bergen Open Research Archive (BORA-UiB) Lofoten Vesterålen ENVELOPE(14.939,14.939,68.754,68.754) Journal of Geophysical Research: Solid Earth 127 3 |
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Open Polar |
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University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
description |
Rifted passive margins exhibit a large variety in the timing, distribution, and amount of magmatism. The factors controlling magmatism during rifted margin formation, remain, however, incompletely understood, partly owing to the complex rifting styles. In this study, we use 2-Dimensional numerical models to investigate the effects of depth-dependent wide rifting and lithospheric counterflow on magmatism during rifted margin formation. Results show that a strong crust promotes narrow margins with a sharp transition to normal thickness oceanic crust whereas a weak crust promotes depth-dependent wide rifting, with preferential removal of mantle lithosphere, leading to formation of wide margins with over-thickened (>18 km) igneous crust in the distal margin. Counterflow of depleted lithospheric mantle, in contrast, may delay syn-rift magmatism, and result in exhumed a-magmatic continental mantle at narrow margins. The combination of wide rifting and lithospheric counterflow results in magma-poor wide margins, with in some cases a transition to excess magmatic activity at breakup. Our models provide an explanation for the contrasting magmatic productivity at narrow and wide rifted margins, such as observed in the Lofoten-Vesterålen, Newfoundland, Kwanza Basin, and Orange Basin margins. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Lu, Gang Huismans, Ritske Sipke |
spellingShingle |
Lu, Gang Huismans, Ritske Sipke Magmatism at Passive Margins: Effects of Depth-Dependent Wide Rifting and Lithospheric Counterflow |
author_facet |
Lu, Gang Huismans, Ritske Sipke |
author_sort |
Lu, Gang |
title |
Magmatism at Passive Margins: Effects of Depth-Dependent Wide Rifting and Lithospheric Counterflow |
title_short |
Magmatism at Passive Margins: Effects of Depth-Dependent Wide Rifting and Lithospheric Counterflow |
title_full |
Magmatism at Passive Margins: Effects of Depth-Dependent Wide Rifting and Lithospheric Counterflow |
title_fullStr |
Magmatism at Passive Margins: Effects of Depth-Dependent Wide Rifting and Lithospheric Counterflow |
title_full_unstemmed |
Magmatism at Passive Margins: Effects of Depth-Dependent Wide Rifting and Lithospheric Counterflow |
title_sort |
magmatism at passive margins: effects of depth-dependent wide rifting and lithospheric counterflow |
publisher |
Wiley |
publishDate |
2022 |
url |
https://hdl.handle.net/11250/3055619 https://doi.org/10.1029/2021JB023046 |
long_lat |
ENVELOPE(14.939,14.939,68.754,68.754) |
geographic |
Lofoten Vesterålen |
geographic_facet |
Lofoten Vesterålen |
genre |
Lofoten Newfoundland Vesterålen |
genre_facet |
Lofoten Newfoundland Vesterålen |
op_source |
e2021JB023046 Journal of Geophysical Research (JGR): Solid Earth 127 3 |
op_relation |
Sigma2: NN4704K Sigma2: NS4704K urn:issn:2169-9313 https://hdl.handle.net/11250/3055619 https://doi.org/10.1029/2021JB023046 cristin:2020401 Journal of Geophysical Research: Solid Earth. 2022, 127 (3), e2021JB023046. |
op_rights |
Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright 2022 The Authors |
op_doi |
https://doi.org/10.1029/2021JB023046 |
container_title |
Journal of Geophysical Research: Solid Earth |
container_volume |
127 |
container_issue |
3 |
_version_ |
1766064020197998592 |