Combined bulk-rock Hf- and Nd-isotope compositions of Mesoarchaean metavolcanic rocks from the Ivisaartoq Supracrustal Belt, SW Greenland: Deviations from the mantle array caused by crustal recycling
Bulk-rock Lu-Hf and Sm-Nd isotope compositions, as well as major and trace element data are presented for metavolcanic rocks from the Mesoarchaean (ca. 3075 Ma) Ivisaartoq Supracrustal Belt in the Nuuk region of southern West Greenland. The epsilon Hf-t calculated at 3075 Ma range from +0.8 to +3.1...
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ftubkoeln:oai:USBKOELN.ub.uni-koeln.de:28838 2023-05-15T16:28:44+02:00 Combined bulk-rock Hf- and Nd-isotope compositions of Mesoarchaean metavolcanic rocks from the Ivisaartoq Supracrustal Belt, SW Greenland: Deviations from the mantle array caused by crustal recycling Szilas, Kristoffer Hoffmann, J. Elis Schulz, Toni Hansmeier, Christina Polat, Ali Viehmann, Sebastian Kasper, Haino Uwe Muenker, Carsten 2016 https://kups.ub.uni-koeln.de/28838/ eng eng ELSEVIER GMBH Szilas, Kristoffer orcid:0000-0002-5541-306X , Hoffmann, J. Elis orcid:0000-0001-6670-1393 , Schulz, Toni orcid:0000-0003-1248-7832 , Hansmeier, Christina, Polat, Ali, Viehmann, Sebastian orcid:0000-0001-6138-5862 , Kasper, Haino Uwe and Muenker, Carsten (2016). Combined bulk-rock Hf- and Nd-isotope compositions of Mesoarchaean metavolcanic rocks from the Ivisaartoq Supracrustal Belt, SW Greenland: Deviations from the mantle array caused by crustal recycling. Chem Erde-Geochem., 76 (4). S. 543 - 555. MUNICH: ELSEVIER GMBH. ISSN 1611-5864 ddc:no doc-type:article publishedVersion 2016 ftubkoeln 2022-11-09T07:21:55Z Bulk-rock Lu-Hf and Sm-Nd isotope compositions, as well as major and trace element data are presented for metavolcanic rocks from the Mesoarchaean (ca. 3075 Ma) Ivisaartoq Supracrustal Belt in the Nuuk region of southern West Greenland. The epsilon Hf-t calculated at 3075 Ma range from +0.8 to +3.1 and the corresponding epsilon Nd-t values range from +0.7 to +3.6, which forms an array that is displaced off the mantle array for these two isotopic systems. Primitive mantle normalized trace element plots of the metabasalts display negative Nb- and Ti-anomalies in combination with the elevated Th abundances, which is consistent with a subduction zone affinity as proposed by previous studies of this metavolcanic belt. No significant correlations are observed between the isotope compositions and proxies of shallow crustal contamination in the Ivisaartoq rocks, despite clear evidence for inherited Eoarchaean zircon [Polat et al. (2009a) Chemical Geology 268, 248-271], which would have dominated the bulk-rock Hf-isotope budget. Furthermore, the measured samples are less radiogenic than the estimate for the depleted mantle composition at 3075 Ma. The lack of isotope and trace element correlation suggests incomplete equilibration between the crustal contaminant and the parental Ivisaartoq melts. We prefer a petrogenetic model with some combination of slab-derived metasomatism of the mantle source region for the Ivisaartoq magmas, which homogenized their trace element contents, in combination with the incorporation of granitoid residue with unradiogenic Hf-isotope composition at higher degrees of partial melting and finally the eruption of mechanically entrained Eoarchaean crust without significant chemical equilibration. The geochemical arc-affinity and lower than depleted mantle (DM) isotope compositions of these metavolcanic rocks support the notion that crustal recycling and plate tectonics has been operating on Earth since at least the Mesoarchaean Eon. (C) 2016 Elsevier GmbH. All rights reserved. Article in Journal/Newspaper Greenland Nuuk Cologne University: KUPS Greenland Ivisaartoq ENVELOPE(-49.917,-49.917,64.767,64.767) Nuuk ENVELOPE(-52.150,-52.150,68.717,68.717) |
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Open Polar |
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Cologne University: KUPS |
op_collection_id |
ftubkoeln |
language |
English |
topic |
ddc:no |
spellingShingle |
ddc:no Szilas, Kristoffer Hoffmann, J. Elis Schulz, Toni Hansmeier, Christina Polat, Ali Viehmann, Sebastian Kasper, Haino Uwe Muenker, Carsten Combined bulk-rock Hf- and Nd-isotope compositions of Mesoarchaean metavolcanic rocks from the Ivisaartoq Supracrustal Belt, SW Greenland: Deviations from the mantle array caused by crustal recycling |
topic_facet |
ddc:no |
description |
Bulk-rock Lu-Hf and Sm-Nd isotope compositions, as well as major and trace element data are presented for metavolcanic rocks from the Mesoarchaean (ca. 3075 Ma) Ivisaartoq Supracrustal Belt in the Nuuk region of southern West Greenland. The epsilon Hf-t calculated at 3075 Ma range from +0.8 to +3.1 and the corresponding epsilon Nd-t values range from +0.7 to +3.6, which forms an array that is displaced off the mantle array for these two isotopic systems. Primitive mantle normalized trace element plots of the metabasalts display negative Nb- and Ti-anomalies in combination with the elevated Th abundances, which is consistent with a subduction zone affinity as proposed by previous studies of this metavolcanic belt. No significant correlations are observed between the isotope compositions and proxies of shallow crustal contamination in the Ivisaartoq rocks, despite clear evidence for inherited Eoarchaean zircon [Polat et al. (2009a) Chemical Geology 268, 248-271], which would have dominated the bulk-rock Hf-isotope budget. Furthermore, the measured samples are less radiogenic than the estimate for the depleted mantle composition at 3075 Ma. The lack of isotope and trace element correlation suggests incomplete equilibration between the crustal contaminant and the parental Ivisaartoq melts. We prefer a petrogenetic model with some combination of slab-derived metasomatism of the mantle source region for the Ivisaartoq magmas, which homogenized their trace element contents, in combination with the incorporation of granitoid residue with unradiogenic Hf-isotope composition at higher degrees of partial melting and finally the eruption of mechanically entrained Eoarchaean crust without significant chemical equilibration. The geochemical arc-affinity and lower than depleted mantle (DM) isotope compositions of these metavolcanic rocks support the notion that crustal recycling and plate tectonics has been operating on Earth since at least the Mesoarchaean Eon. (C) 2016 Elsevier GmbH. All rights reserved. |
format |
Article in Journal/Newspaper |
author |
Szilas, Kristoffer Hoffmann, J. Elis Schulz, Toni Hansmeier, Christina Polat, Ali Viehmann, Sebastian Kasper, Haino Uwe Muenker, Carsten |
author_facet |
Szilas, Kristoffer Hoffmann, J. Elis Schulz, Toni Hansmeier, Christina Polat, Ali Viehmann, Sebastian Kasper, Haino Uwe Muenker, Carsten |
author_sort |
Szilas, Kristoffer |
title |
Combined bulk-rock Hf- and Nd-isotope compositions of Mesoarchaean metavolcanic rocks from the Ivisaartoq Supracrustal Belt, SW Greenland: Deviations from the mantle array caused by crustal recycling |
title_short |
Combined bulk-rock Hf- and Nd-isotope compositions of Mesoarchaean metavolcanic rocks from the Ivisaartoq Supracrustal Belt, SW Greenland: Deviations from the mantle array caused by crustal recycling |
title_full |
Combined bulk-rock Hf- and Nd-isotope compositions of Mesoarchaean metavolcanic rocks from the Ivisaartoq Supracrustal Belt, SW Greenland: Deviations from the mantle array caused by crustal recycling |
title_fullStr |
Combined bulk-rock Hf- and Nd-isotope compositions of Mesoarchaean metavolcanic rocks from the Ivisaartoq Supracrustal Belt, SW Greenland: Deviations from the mantle array caused by crustal recycling |
title_full_unstemmed |
Combined bulk-rock Hf- and Nd-isotope compositions of Mesoarchaean metavolcanic rocks from the Ivisaartoq Supracrustal Belt, SW Greenland: Deviations from the mantle array caused by crustal recycling |
title_sort |
combined bulk-rock hf- and nd-isotope compositions of mesoarchaean metavolcanic rocks from the ivisaartoq supracrustal belt, sw greenland: deviations from the mantle array caused by crustal recycling |
publisher |
ELSEVIER GMBH |
publishDate |
2016 |
url |
https://kups.ub.uni-koeln.de/28838/ |
long_lat |
ENVELOPE(-49.917,-49.917,64.767,64.767) ENVELOPE(-52.150,-52.150,68.717,68.717) |
geographic |
Greenland Ivisaartoq Nuuk |
geographic_facet |
Greenland Ivisaartoq Nuuk |
genre |
Greenland Nuuk |
genre_facet |
Greenland Nuuk |
op_relation |
Szilas, Kristoffer orcid:0000-0002-5541-306X , Hoffmann, J. Elis orcid:0000-0001-6670-1393 , Schulz, Toni orcid:0000-0003-1248-7832 , Hansmeier, Christina, Polat, Ali, Viehmann, Sebastian orcid:0000-0001-6138-5862 , Kasper, Haino Uwe and Muenker, Carsten (2016). Combined bulk-rock Hf- and Nd-isotope compositions of Mesoarchaean metavolcanic rocks from the Ivisaartoq Supracrustal Belt, SW Greenland: Deviations from the mantle array caused by crustal recycling. Chem Erde-Geochem., 76 (4). S. 543 - 555. MUNICH: ELSEVIER GMBH. ISSN 1611-5864 |
_version_ |
1766018408583790592 |