Temporal evolution of 142Nd signatures in SW Greenland from high precision MC-ICP-MS measurements
Measurements of 142Nd 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 validat...
Published in: | Chemical Geology |
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Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
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(de9e0e0b-d148-4af3-8728-7bf83335996e).html https://doi.org/10.1016/j.chemgeo.2022.121141 https://www.sciencedirect.com/science/article/pii/S0009254122004351 |
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ftcopenhagenunip:oai:pure.atira.dk:publications/de9e0e0b-d148-4af3-8728-7bf83335996e 2023-05-15T13:21:43+02:00 Temporal evolution of 142Nd 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 https://curis.ku.dk/portal/da/publications/temporal-evolution-of-142nd-signatures-in-sw-greenland-from-high-precision-mcicpms-measurements(de9e0e0b-d148-4af3-8728-7bf83335996e).html https://doi.org/10.1016/j.chemgeo.2022.121141 https://www.sciencedirect.com/science/article/pii/S0009254122004351 eng eng info:eu-repo/semantics/restrictedAccess Hasenstab-Dübeler , E , Tusch , J , Hoffmann , J E , Fischer-Gödde , M , Szilas , K & Münker , C 2022 , ' Temporal evolution of 142Nd signatures in SW Greenland from high precision MC-ICP-MS measurements ' , Chemical Geology , pp. 121141 . https://doi.org/10.1016/j.chemgeo.2022.121141 Hadean differentiation Archean Mantle heterogeneity Isua supracrustal belt: 142Nd MC ICP-MS article 2022 ftcopenhagenunip https://doi.org/10.1016/j.chemgeo.2022.121141 2022-10-19T22:53:07Z Measurements of 142Nd 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 142-143Nd isotope systematics, by both TIMS and MC-ICP-MS. Our μ142Nd 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 142,143Nd/144Nd 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+0.0454.426−0.064+0.084 4.426−0.055+0.042 Ga. Moreover, we can resolve a statistically significant decrease of 142Nd/144Nd isotope compositions in the ambient mantle of SW Greenland that already started to commence by Eoarchean time, between ~3.8 Ga (μ142Nd = +13.0 ± 1.1) and ~ 3.72 Ga (μ142Nd = +9.8 ± 1.0). Even lower but homogeneous μ142Nd values of +3.8 ± 1.1 are found in ~3.4 Ga mantle-derived rocks from the Ameralik dike swarms. Our study reveals that ε143Nd(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 μ142Nd 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 147Sm143Nd 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 |
Hadean differentiation Archean Mantle heterogeneity Isua supracrustal belt: 142Nd MC ICP-MS |
spellingShingle |
Hadean differentiation Archean Mantle heterogeneity Isua supracrustal belt: 142Nd MC ICP-MS Hasenstab-Dübeler, Eric Tusch, Jonas Hoffmann, J. Elis Fischer-Gödde, Mario Szilas, Kristoffer Münker, Carsten Temporal evolution of 142Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
topic_facet |
Hadean differentiation Archean Mantle heterogeneity Isua supracrustal belt: 142Nd MC ICP-MS |
description |
Measurements of 142Nd 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 142-143Nd isotope systematics, by both TIMS and MC-ICP-MS. Our μ142Nd 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 142,143Nd/144Nd 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+0.0454.426−0.064+0.084 4.426−0.055+0.042 Ga. Moreover, we can resolve a statistically significant decrease of 142Nd/144Nd isotope compositions in the ambient mantle of SW Greenland that already started to commence by Eoarchean time, between ~3.8 Ga (μ142Nd = +13.0 ± 1.1) and ~ 3.72 Ga (μ142Nd = +9.8 ± 1.0). Even lower but homogeneous μ142Nd values of +3.8 ± 1.1 are found in ~3.4 Ga mantle-derived rocks from the Ameralik dike swarms. Our study reveals that ε143Nd(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 μ142Nd 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 147Sm143Nd 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 142Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
title_short |
Temporal evolution of 142Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
title_full |
Temporal evolution of 142Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
title_fullStr |
Temporal evolution of 142Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
title_full_unstemmed |
Temporal evolution of 142Nd signatures in SW Greenland from high precision MC-ICP-MS measurements |
title_sort |
temporal evolution of 142nd 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(de9e0e0b-d148-4af3-8728-7bf83335996e).html https://doi.org/10.1016/j.chemgeo.2022.121141 https://www.sciencedirect.com/science/article/pii/S0009254122004351 |
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 142Nd signatures in SW Greenland from high precision MC-ICP-MS measurements ' , Chemical Geology , pp. 121141 . https://doi.org/10.1016/j.chemgeo.2022.121141 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
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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1766361056504971264 |