Temporal evolution of 142 Nd signatures in SW Greenland from high precision MC-ICP-MS measurements
Measurements of 142 Nd isotope signatures in Archean rocks are a powerful tool to investigate the earliest silicate differentiation events on Earth. Here, we introduce a new analytical protocol that allows high precision radiogenic and mass-independent Nd isotope measurements by MC-ICP-MS. To valida...
Published in: | Chemical Geology |
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Main Authors: | , , , , , |
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Language: | English |
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2022
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Online Access: | https://curis.ku.dk/portal/da/publications/temporal-evolution-of-142nd-signatures-in-sw-greenland-from-high-precision-mcicpms-measurements(7d630ece-8793-434b-996f-b1b01f3a967b).html https://doi.org/10.1016/j.chemgeo.2022.121141 https://curis.ku.dk/ws/files/332118363/Temporal_evolution.pdf |
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ftcopenhagenunip:oai:pure.atira.dk:publications/7d630ece-8793-434b-996f-b1b01f3a967b 2024-06-09T07:38:13+00:00 Temporal evolution of 142 Nd signatures in SW Greenland from high precision MC-ICP-MS measurements Hasenstab-Dübeler, Eric Tusch, Jonas Hoffmann, J. Elis Fischer-Gödde, Mario Szilas, Kristoffer Münker, Carsten 2022 application/pdf https://curis.ku.dk/portal/da/publications/temporal-evolution-of-142nd-signatures-in-sw-greenland-from-high-precision-mcicpms-measurements(7d630ece-8793-434b-996f-b1b01f3a967b).html https://doi.org/10.1016/j.chemgeo.2022.121141 https://curis.ku.dk/ws/files/332118363/Temporal_evolution.pdf eng eng info:eu-repo/semantics/openAccess Hasenstab-Dübeler , E , Tusch , J , Hoffmann , J E , Fischer-Gödde , M , Szilas , K & Münker , C 2022 , ' Temporal evolution of 142 Nd signatures in SW Greenland from high precision MC-ICP-MS measurements ' , Chemical Geology , vol. 614 , 121141 . https://doi.org/10.1016/j.chemgeo.2022.121141 Archean Hadean differentiation Isua supracrustal belt: 142Nd Mantle heterogeneity MC ICP-MS article 2022 ftcopenhagenunip https://doi.org/10.1016/j.chemgeo.2022.121141 2024-05-16T11:29:26Z Measurements of 142 Nd isotope signatures in Archean rocks are a powerful tool to investigate the earliest silicate differentiation events on Earth. Here, we introduce a new analytical protocol that allows high precision radiogenic and mass-independent Nd isotope measurements by MC-ICP-MS. To validate our method, we have measured well-characterized ∼3.72 to ∼3.8 Ga samples from the Eoarchean Itsaq Gneiss Complex and associated supracrustal belts, as well as Mesoarchean greenstones and a Proterozoic dike in SW Greenland, including lithostratigraphic units that were previously analyzed for 142-143 Nd isotope systematics, by both TIMS and MC-ICP-MS. Our μ 142 Nd values for ∼3.72 to ∼3.8 Ga rocks from the Isua region range from +9.2 ± 2.6 to +13.2 ± 1.1 ppm and are in good agreement with previous studies. Using coupled 142,143 Nd/ 144 Nd isotope systematics from our data for ∼3.8 Ga mafic-ultramafic successions from the Isua region, we can confirm previous age constraints on the earliest silicate differentiation events with differentiation age of 4.390 −0.060 +0.045 Ga. Moreover, we can resolve a statistically significant decrease of 142 Nd/ 144 Nd isotope compositions in the ambient mantle of SW Greenland that already started to commence by Eoarchean time, between ∼3.8 Ga (μ 142 Nd = +13.0 ± 1.1) and ∼ 3.72 Ga (μ 142 Nd = +9.8 ± 1.0). Even lower but homogeneous μ 142 Nd values of +3.8 ± 1.1 are found in ∼3.4 Ga mantle-derived rocks from the Ameralik dike swarms. Our study reveals that ε 143 Nd (i) and εHf (i) values of Isua rocks scatter more than it would be expected from a single stage differentiation event as implied from nearly uniform μ 142 Nd values, suggesting that the previously described decoupling of Hf and Nd isotopes is not a primordial magma ocean signature. Instead, we conclude that some of second stage processes like younger mantle depletion events or recycling of subducted material affected the 147 Sm[sbnd] 143 Nd isotope systematics. The preservation of pristine whole-rock isochrons largely rules ... Article in Journal/Newspaper Ameralik Greenland University of Copenhagen: Research Ameralik ENVELOPE(-51.000,-51.000,64.117,64.117) Greenland Chemical Geology 614 121141 |
institution |
Open Polar |
collection |
University of Copenhagen: Research |
op_collection_id |
ftcopenhagenunip |
language |
English |
topic |
Archean Hadean differentiation Isua supracrustal belt: 142Nd Mantle heterogeneity MC ICP-MS |
spellingShingle |
Archean Hadean differentiation Isua supracrustal belt: 142Nd Mantle heterogeneity MC ICP-MS Hasenstab-Dübeler, Eric Tusch, Jonas Hoffmann, J. Elis Fischer-Gödde, Mario Szilas, Kristoffer Münker, Carsten Temporal evolution of 142 Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
topic_facet |
Archean Hadean differentiation Isua supracrustal belt: 142Nd Mantle heterogeneity MC ICP-MS |
description |
Measurements of 142 Nd isotope signatures in Archean rocks are a powerful tool to investigate the earliest silicate differentiation events on Earth. Here, we introduce a new analytical protocol that allows high precision radiogenic and mass-independent Nd isotope measurements by MC-ICP-MS. To validate our method, we have measured well-characterized ∼3.72 to ∼3.8 Ga samples from the Eoarchean Itsaq Gneiss Complex and associated supracrustal belts, as well as Mesoarchean greenstones and a Proterozoic dike in SW Greenland, including lithostratigraphic units that were previously analyzed for 142-143 Nd isotope systematics, by both TIMS and MC-ICP-MS. Our μ 142 Nd values for ∼3.72 to ∼3.8 Ga rocks from the Isua region range from +9.2 ± 2.6 to +13.2 ± 1.1 ppm and are in good agreement with previous studies. Using coupled 142,143 Nd/ 144 Nd isotope systematics from our data for ∼3.8 Ga mafic-ultramafic successions from the Isua region, we can confirm previous age constraints on the earliest silicate differentiation events with differentiation age of 4.390 −0.060 +0.045 Ga. Moreover, we can resolve a statistically significant decrease of 142 Nd/ 144 Nd isotope compositions in the ambient mantle of SW Greenland that already started to commence by Eoarchean time, between ∼3.8 Ga (μ 142 Nd = +13.0 ± 1.1) and ∼ 3.72 Ga (μ 142 Nd = +9.8 ± 1.0). Even lower but homogeneous μ 142 Nd values of +3.8 ± 1.1 are found in ∼3.4 Ga mantle-derived rocks from the Ameralik dike swarms. Our study reveals that ε 143 Nd (i) and εHf (i) values of Isua rocks scatter more than it would be expected from a single stage differentiation event as implied from nearly uniform μ 142 Nd values, suggesting that the previously described decoupling of Hf and Nd isotopes is not a primordial magma ocean signature. Instead, we conclude that some of second stage processes like younger mantle depletion events or recycling of subducted material affected the 147 Sm[sbnd] 143 Nd isotope systematics. The preservation of pristine whole-rock isochrons largely rules ... |
format |
Article in Journal/Newspaper |
author |
Hasenstab-Dübeler, Eric Tusch, Jonas Hoffmann, J. Elis Fischer-Gödde, Mario Szilas, Kristoffer Münker, Carsten |
author_facet |
Hasenstab-Dübeler, Eric Tusch, Jonas Hoffmann, J. Elis Fischer-Gödde, Mario Szilas, Kristoffer Münker, Carsten |
author_sort |
Hasenstab-Dübeler, Eric |
title |
Temporal evolution of 142 Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
title_short |
Temporal evolution of 142 Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
title_full |
Temporal evolution of 142 Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
title_fullStr |
Temporal evolution of 142 Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
title_full_unstemmed |
Temporal evolution of 142 Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
title_sort |
temporal evolution of 142 nd signatures in sw greenland from high precision mc-icp-ms measurements |
publishDate |
2022 |
url |
https://curis.ku.dk/portal/da/publications/temporal-evolution-of-142nd-signatures-in-sw-greenland-from-high-precision-mcicpms-measurements(7d630ece-8793-434b-996f-b1b01f3a967b).html https://doi.org/10.1016/j.chemgeo.2022.121141 https://curis.ku.dk/ws/files/332118363/Temporal_evolution.pdf |
long_lat |
ENVELOPE(-51.000,-51.000,64.117,64.117) |
geographic |
Ameralik Greenland |
geographic_facet |
Ameralik Greenland |
genre |
Ameralik Greenland |
genre_facet |
Ameralik Greenland |
op_source |
Hasenstab-Dübeler , E , Tusch , J , Hoffmann , J E , Fischer-Gödde , M , Szilas , K & Münker , C 2022 , ' Temporal evolution of 142 Nd signatures in SW Greenland from high precision MC-ICP-MS measurements ' , Chemical Geology , vol. 614 , 121141 . https://doi.org/10.1016/j.chemgeo.2022.121141 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.chemgeo.2022.121141 |
container_title |
Chemical Geology |
container_volume |
614 |
container_start_page |
121141 |
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1801371120276865024 |