High-pressure Reactive Melt Stagnation Recorded in Abyssal Pyroxenites from the Ultraslow-spreading Lena Trough, Arctic Ocean
Pyroxenites are an essential component in petrological and geochemical models for melt formation at mid-ocean ridges and ocean islands. Despite their rarity, their origin has been widely discussed and various processes have been invoked for their formation. Here, we present a detailed study of the m...
Published in: | Journal of Petrology |
---|---|
Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Oxford Univ. Press
2014
|
Subjects: | |
Online Access: | https://oceanrep.geomar.de/id/eprint/23226/ https://oceanrep.geomar.de/id/eprint/23226/1/J.%20Petrology-2014-Laukert-427-58.pdf https://doi.org/10.1093/petrology/egt073 |
id |
ftoceanrep:oai:oceanrep.geomar.de:23226 |
---|---|
record_format |
openpolar |
spelling |
ftoceanrep:oai:oceanrep.geomar.de:23226 2023-05-15T14:27:13+02:00 High-pressure Reactive Melt Stagnation Recorded in Abyssal Pyroxenites from the Ultraslow-spreading Lena Trough, Arctic Ocean Laukert, Georgi von der Handt, Annette Hellebrand, Eric Snow, Jonathan E. Hoppe, Peter Klugel, Andreas 2014 text https://oceanrep.geomar.de/id/eprint/23226/ https://oceanrep.geomar.de/id/eprint/23226/1/J.%20Petrology-2014-Laukert-427-58.pdf https://doi.org/10.1093/petrology/egt073 en eng Oxford Univ. Press https://oceanrep.geomar.de/id/eprint/23226/1/J.%20Petrology-2014-Laukert-427-58.pdf Laukert, G. , von der Handt, A., Hellebrand, E., Snow, J. E., Hoppe, P. and Klugel, A. (2014) High-pressure Reactive Melt Stagnation Recorded in Abyssal Pyroxenites from the Ultraslow-spreading Lena Trough, Arctic Ocean. Journal of Petrology, 55 (2). pp. 427-458. DOI 10.1093/petrology/egt073 <https://doi.org/10.1093/petrology%2Fegt073>. doi:10.1093/petrology/egt073 info:eu-repo/semantics/restrictedAccess Article PeerReviewed 2014 ftoceanrep https://doi.org/10.1093/petrology/egt073 2023-04-07T15:12:02Z Pyroxenites are an essential component in petrological and geochemical models for melt formation at mid-ocean ridges and ocean islands. Despite their rarity, their origin has been widely discussed and various processes have been invoked for their formation. Here, we present a detailed study of the microtextures and major, minor and trace element compositions of relatively fresh pyroxenites and associated harzburgites from the ultraslow-spreading Lena Trough, Arctic Ocean. Microtextural and geochemical characteristics suggest an origin by magmatic assimilation–fractional crystallization with a high ratio of mass crystallized to mass assimilated. The major element compositions of pyroxenes suggest that this process occurred at high pressures (>0·7 GPa), although interstitial plagioclase in two of the pyroxenites indicates that melt–rock reaction continued at lower pressures. The parental melt to the pyroxenites was most probably depleted mid-ocean ridge basalt similar to basalts from the North Lena Trough and westernmost Gakkel Ridge; basalts from the Central Lena Trough cannot have functioned as parental melts. The melt was generated close to the garnet–spinel facies transition by variable degrees of partial melting and reacted with the local refractory harzburgite. Pyroxenites from this study provide further evidence, together with plagioclase-bearing and vein-bearing peridotites, for significant melt stagnation below the Lena Trough that occurred over a range of depths, either continuously or stepwise. Comparison with abyssal pyroxenites reveals common characteristics, suggesting that, consistent with results of high-pressure crystallization experiments, they mark the onset of (reactive) crystallization of melts passing through the deeper parts of the mid-ocean ridge plumbing system. Article in Journal/Newspaper Arctic Arctic Arctic Ocean OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Arctic Arctic Ocean Gakkel Ridge ENVELOPE(90.000,90.000,87.000,87.000) Journal of Petrology 55 2 427 458 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Pyroxenites are an essential component in petrological and geochemical models for melt formation at mid-ocean ridges and ocean islands. Despite their rarity, their origin has been widely discussed and various processes have been invoked for their formation. Here, we present a detailed study of the microtextures and major, minor and trace element compositions of relatively fresh pyroxenites and associated harzburgites from the ultraslow-spreading Lena Trough, Arctic Ocean. Microtextural and geochemical characteristics suggest an origin by magmatic assimilation–fractional crystallization with a high ratio of mass crystallized to mass assimilated. The major element compositions of pyroxenes suggest that this process occurred at high pressures (>0·7 GPa), although interstitial plagioclase in two of the pyroxenites indicates that melt–rock reaction continued at lower pressures. The parental melt to the pyroxenites was most probably depleted mid-ocean ridge basalt similar to basalts from the North Lena Trough and westernmost Gakkel Ridge; basalts from the Central Lena Trough cannot have functioned as parental melts. The melt was generated close to the garnet–spinel facies transition by variable degrees of partial melting and reacted with the local refractory harzburgite. Pyroxenites from this study provide further evidence, together with plagioclase-bearing and vein-bearing peridotites, for significant melt stagnation below the Lena Trough that occurred over a range of depths, either continuously or stepwise. Comparison with abyssal pyroxenites reveals common characteristics, suggesting that, consistent with results of high-pressure crystallization experiments, they mark the onset of (reactive) crystallization of melts passing through the deeper parts of the mid-ocean ridge plumbing system. |
format |
Article in Journal/Newspaper |
author |
Laukert, Georgi von der Handt, Annette Hellebrand, Eric Snow, Jonathan E. Hoppe, Peter Klugel, Andreas |
spellingShingle |
Laukert, Georgi von der Handt, Annette Hellebrand, Eric Snow, Jonathan E. Hoppe, Peter Klugel, Andreas High-pressure Reactive Melt Stagnation Recorded in Abyssal Pyroxenites from the Ultraslow-spreading Lena Trough, Arctic Ocean |
author_facet |
Laukert, Georgi von der Handt, Annette Hellebrand, Eric Snow, Jonathan E. Hoppe, Peter Klugel, Andreas |
author_sort |
Laukert, Georgi |
title |
High-pressure Reactive Melt Stagnation Recorded in Abyssal Pyroxenites from the Ultraslow-spreading Lena Trough, Arctic Ocean |
title_short |
High-pressure Reactive Melt Stagnation Recorded in Abyssal Pyroxenites from the Ultraslow-spreading Lena Trough, Arctic Ocean |
title_full |
High-pressure Reactive Melt Stagnation Recorded in Abyssal Pyroxenites from the Ultraslow-spreading Lena Trough, Arctic Ocean |
title_fullStr |
High-pressure Reactive Melt Stagnation Recorded in Abyssal Pyroxenites from the Ultraslow-spreading Lena Trough, Arctic Ocean |
title_full_unstemmed |
High-pressure Reactive Melt Stagnation Recorded in Abyssal Pyroxenites from the Ultraslow-spreading Lena Trough, Arctic Ocean |
title_sort |
high-pressure reactive melt stagnation recorded in abyssal pyroxenites from the ultraslow-spreading lena trough, arctic ocean |
publisher |
Oxford Univ. Press |
publishDate |
2014 |
url |
https://oceanrep.geomar.de/id/eprint/23226/ https://oceanrep.geomar.de/id/eprint/23226/1/J.%20Petrology-2014-Laukert-427-58.pdf https://doi.org/10.1093/petrology/egt073 |
long_lat |
ENVELOPE(90.000,90.000,87.000,87.000) |
geographic |
Arctic Arctic Ocean Gakkel Ridge |
geographic_facet |
Arctic Arctic Ocean Gakkel Ridge |
genre |
Arctic Arctic Arctic Ocean |
genre_facet |
Arctic Arctic Arctic Ocean |
op_relation |
https://oceanrep.geomar.de/id/eprint/23226/1/J.%20Petrology-2014-Laukert-427-58.pdf Laukert, G. , von der Handt, A., Hellebrand, E., Snow, J. E., Hoppe, P. and Klugel, A. (2014) High-pressure Reactive Melt Stagnation Recorded in Abyssal Pyroxenites from the Ultraslow-spreading Lena Trough, Arctic Ocean. Journal of Petrology, 55 (2). pp. 427-458. DOI 10.1093/petrology/egt073 <https://doi.org/10.1093/petrology%2Fegt073>. doi:10.1093/petrology/egt073 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1093/petrology/egt073 |
container_title |
Journal of Petrology |
container_volume |
55 |
container_issue |
2 |
container_start_page |
427 |
op_container_end_page |
458 |
_version_ |
1766300853921120256 |