Ancient refractory asthenosphere revealed by mantle re-melting at the Arctic Mid Atlantic Ridge
The upper mantle is a heterogeneous mixture of refractory and recycled crustal domains. The recycled portions, more fertile and thus preferentially melted, dominate the composition of the basalts erupted on the surface, whereas the imprint of melting of the refractory counterparts is more difficult...
Published in: | Earth and Planetary Science Letters |
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Online Access: | http://hdl.handle.net/11571/1452217 https://doi.org/10.1016/j.epsl.2021.116981 |
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ftunivpavia:oai:iris.unipv.it:11571/1452217 2024-02-27T08:37:24+00:00 Ancient refractory asthenosphere revealed by mantle re-melting at the Arctic Mid Atlantic Ridge Sanfilippo A. Salters V. J. M. Sokolov S. Y. Peyve A. A. Stracke A. Sanfilippo, A. Salters, V. J. M. Sokolov, S. Y. Peyve, A. A. Stracke, A. 2021 STAMPA http://hdl.handle.net/11571/1452217 https://doi.org/10.1016/j.epsl.2021.116981 eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000656494100019 volume:566 journal:EARTH AND PLANETARY SCIENCE LETTERS http://hdl.handle.net/11571/1452217 doi:10.1016/j.epsl.2021.116981 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85106226580 depleted mantle Knipovich Ridge magma mixing Mid Ocean Ridge Basalt Nd-Hf isotopes info:eu-repo/semantics/article 2021 ftunivpavia https://doi.org/10.1016/j.epsl.2021.116981 2024-01-31T17:51:53Z The upper mantle is a heterogeneous mixture of refractory and recycled crustal domains. The recycled portions, more fertile and thus preferentially melted, dominate the composition of the basalts erupted on the surface, whereas the imprint of melting of the refractory counterparts is more difficult to discern from the basalt chemistry. Contrasting radiogenic isotopic signatures of mid-ocean ridge basalts and oceanic mantle, however, show that Hf isotope ratios may provide hints for melting of refractory source materials despite ubiquitous magma mixing during ascent and stalling in the crust. This property may allow identifying contributions from depleted mantle materials unseen in other isotope systematics in basalts. Here, we show that basalts from Mohns and Knipovich ridges, two >500-km long oblique super-segments in the Arctic Atlantic, have distinctly high Hf isotope ratios, not mirrored by comparatively high Nd and low Sr and Pb isotope ratios. These compositions can be explained if a highly depleted asthenospheric mantle melts beneath this section of the Arctic Mid Atlantic Ridge. We argue that this depleted source consists of high proportions of ancient (>1 Ga), ultra-depleted mantle, previously drained of enriched components before being re-melted in its current location following a recent ridge-jump, allowing the identification of ultra-depleted mantle components in the arctic subridge mantle. Article in Journal/Newspaper Arctic IRIS UNIPV (Università degli studi di Pavia) Arctic Mid-Atlantic Ridge Knipovich Ridge ENVELOPE(7.074,7.074,75.712,75.712) Earth and Planetary Science Letters 566 116981 |
institution |
Open Polar |
collection |
IRIS UNIPV (Università degli studi di Pavia) |
op_collection_id |
ftunivpavia |
language |
English |
topic |
depleted mantle Knipovich Ridge magma mixing Mid Ocean Ridge Basalt Nd-Hf isotopes |
spellingShingle |
depleted mantle Knipovich Ridge magma mixing Mid Ocean Ridge Basalt Nd-Hf isotopes Sanfilippo A. Salters V. J. M. Sokolov S. Y. Peyve A. A. Stracke A. Ancient refractory asthenosphere revealed by mantle re-melting at the Arctic Mid Atlantic Ridge |
topic_facet |
depleted mantle Knipovich Ridge magma mixing Mid Ocean Ridge Basalt Nd-Hf isotopes |
description |
The upper mantle is a heterogeneous mixture of refractory and recycled crustal domains. The recycled portions, more fertile and thus preferentially melted, dominate the composition of the basalts erupted on the surface, whereas the imprint of melting of the refractory counterparts is more difficult to discern from the basalt chemistry. Contrasting radiogenic isotopic signatures of mid-ocean ridge basalts and oceanic mantle, however, show that Hf isotope ratios may provide hints for melting of refractory source materials despite ubiquitous magma mixing during ascent and stalling in the crust. This property may allow identifying contributions from depleted mantle materials unseen in other isotope systematics in basalts. Here, we show that basalts from Mohns and Knipovich ridges, two >500-km long oblique super-segments in the Arctic Atlantic, have distinctly high Hf isotope ratios, not mirrored by comparatively high Nd and low Sr and Pb isotope ratios. These compositions can be explained if a highly depleted asthenospheric mantle melts beneath this section of the Arctic Mid Atlantic Ridge. We argue that this depleted source consists of high proportions of ancient (>1 Ga), ultra-depleted mantle, previously drained of enriched components before being re-melted in its current location following a recent ridge-jump, allowing the identification of ultra-depleted mantle components in the arctic subridge mantle. |
author2 |
Sanfilippo, A. Salters, V. J. M. Sokolov, S. Y. Peyve, A. A. Stracke, A. |
format |
Article in Journal/Newspaper |
author |
Sanfilippo A. Salters V. J. M. Sokolov S. Y. Peyve A. A. Stracke A. |
author_facet |
Sanfilippo A. Salters V. J. M. Sokolov S. Y. Peyve A. A. Stracke A. |
author_sort |
Sanfilippo A. |
title |
Ancient refractory asthenosphere revealed by mantle re-melting at the Arctic Mid Atlantic Ridge |
title_short |
Ancient refractory asthenosphere revealed by mantle re-melting at the Arctic Mid Atlantic Ridge |
title_full |
Ancient refractory asthenosphere revealed by mantle re-melting at the Arctic Mid Atlantic Ridge |
title_fullStr |
Ancient refractory asthenosphere revealed by mantle re-melting at the Arctic Mid Atlantic Ridge |
title_full_unstemmed |
Ancient refractory asthenosphere revealed by mantle re-melting at the Arctic Mid Atlantic Ridge |
title_sort |
ancient refractory asthenosphere revealed by mantle re-melting at the arctic mid atlantic ridge |
publishDate |
2021 |
url |
http://hdl.handle.net/11571/1452217 https://doi.org/10.1016/j.epsl.2021.116981 |
long_lat |
ENVELOPE(7.074,7.074,75.712,75.712) |
geographic |
Arctic Mid-Atlantic Ridge Knipovich Ridge |
geographic_facet |
Arctic Mid-Atlantic Ridge Knipovich Ridge |
genre |
Arctic |
genre_facet |
Arctic |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000656494100019 volume:566 journal:EARTH AND PLANETARY SCIENCE LETTERS http://hdl.handle.net/11571/1452217 doi:10.1016/j.epsl.2021.116981 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85106226580 |
op_doi |
https://doi.org/10.1016/j.epsl.2021.116981 |
container_title |
Earth and Planetary Science Letters |
container_volume |
566 |
container_start_page |
116981 |
_version_ |
1792044405323988992 |