Sm-Nd and Lu-Hf isotope and trace-element systematics of Mesoarchaean amphibolites, inner Ameralik fjord, southern West Greenland
Fragmented supracrustal rocks are typical components of Archaean high-grade gneiss terranes, such as those in the North Atlantic Craton. Here we present the first major, trace element and Nd-Hf isotope data for amphibolites collected in the yet poorly studied southern inner Ameralik fjord region of...
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ftubkoeln:oai:USBKOELN.ub.uni-koeln.de:39681 2023-05-15T13:21:42+02:00 Sm-Nd and Lu-Hf isotope and trace-element systematics of Mesoarchaean amphibolites, inner Ameralik fjord, southern West Greenland Szilas, Kristoffer Hoffmann, J. Elis Hansmeier, Christina Hollis, Julie A. Muenker, Carsten Viehmann, Sebastian Kasper, Haino U. 2015 https://kups.ub.uni-koeln.de/39681/ eng eng MINERALOGICAL SOC Szilas, Kristoffer orcid:0000-0002-5541-306X , Hoffmann, J. Elis orcid:0000-0001-6670-1393 , Hansmeier, Christina, Hollis, Julie A., Muenker, Carsten, Viehmann, Sebastian orcid:0000-0001-6138-5862 and Kasper, Haino U. (2015). Sm-Nd and Lu-Hf isotope and trace-element systematics of Mesoarchaean amphibolites, inner Ameralik fjord, southern West Greenland. Mineral. Mag., 79 (4). S. 857 - 877. TWICKENHAM: MINERALOGICAL SOC. ISSN 1471-8022 ddc:no doc-type:article publishedVersion 2015 ftubkoeln 2022-11-09T07:26:26Z Fragmented supracrustal rocks are typical components of Archaean high-grade gneiss terranes, such as those in the North Atlantic Craton. Here we present the first major, trace element and Nd-Hf isotope data for amphibolites collected in the yet poorly studied southern inner Ameralik fjord region of southern West Greenland. In addition, new U-Pb zircon ages were obtained from the surrounding TTG gneisses. Based on their trace-element patterns, two different groups of amphibolites can be distinguished. Following screening for post-magmatic alteration and outlying epsilon values, a reduced sample set defines a Sm-147/Nd-143 regression age of 3038 Ma +/- 310 Ma (MSWD = 9.2) and a Lu-176/Hf-176 regression age of 2867 +/- 160 Ma (MSWD = 5.5). Initial epsilon Nd-2970Ma values of the least-altered amphibolites range from 0.0 to +5.7 and initial epsilon Hf-2970Ma range from +0.7 to +10.4, indicating significant isotopic heterogeneity of their mantle sources with involvement of depleted domains as well as crustal sources. Surprisingly, the amphibolites which are apparently most evolved and incompatible element-rich have the most depleted Hf-isotope compositions. This apparent paradox may be explained by the sampling of a local mantle source region with ancient previous melt depletion, which was re-enriched by a fluid component during subduction zone volcanism or alternatively by preferential melting of an ancient pyroxenite component in the mantle source of the enriched rocks. Article in Journal/Newspaper Ameralik Ameralik fjord Greenland North Atlantic Cologne University: KUPS Ameralik ENVELOPE(-51.000,-51.000,64.117,64.117) Greenland |
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Open Polar |
collection |
Cologne University: KUPS |
op_collection_id |
ftubkoeln |
language |
English |
topic |
ddc:no |
spellingShingle |
ddc:no Szilas, Kristoffer Hoffmann, J. Elis Hansmeier, Christina Hollis, Julie A. Muenker, Carsten Viehmann, Sebastian Kasper, Haino U. Sm-Nd and Lu-Hf isotope and trace-element systematics of Mesoarchaean amphibolites, inner Ameralik fjord, southern West Greenland |
topic_facet |
ddc:no |
description |
Fragmented supracrustal rocks are typical components of Archaean high-grade gneiss terranes, such as those in the North Atlantic Craton. Here we present the first major, trace element and Nd-Hf isotope data for amphibolites collected in the yet poorly studied southern inner Ameralik fjord region of southern West Greenland. In addition, new U-Pb zircon ages were obtained from the surrounding TTG gneisses. Based on their trace-element patterns, two different groups of amphibolites can be distinguished. Following screening for post-magmatic alteration and outlying epsilon values, a reduced sample set defines a Sm-147/Nd-143 regression age of 3038 Ma +/- 310 Ma (MSWD = 9.2) and a Lu-176/Hf-176 regression age of 2867 +/- 160 Ma (MSWD = 5.5). Initial epsilon Nd-2970Ma values of the least-altered amphibolites range from 0.0 to +5.7 and initial epsilon Hf-2970Ma range from +0.7 to +10.4, indicating significant isotopic heterogeneity of their mantle sources with involvement of depleted domains as well as crustal sources. Surprisingly, the amphibolites which are apparently most evolved and incompatible element-rich have the most depleted Hf-isotope compositions. This apparent paradox may be explained by the sampling of a local mantle source region with ancient previous melt depletion, which was re-enriched by a fluid component during subduction zone volcanism or alternatively by preferential melting of an ancient pyroxenite component in the mantle source of the enriched rocks. |
format |
Article in Journal/Newspaper |
author |
Szilas, Kristoffer Hoffmann, J. Elis Hansmeier, Christina Hollis, Julie A. Muenker, Carsten Viehmann, Sebastian Kasper, Haino U. |
author_facet |
Szilas, Kristoffer Hoffmann, J. Elis Hansmeier, Christina Hollis, Julie A. Muenker, Carsten Viehmann, Sebastian Kasper, Haino U. |
author_sort |
Szilas, Kristoffer |
title |
Sm-Nd and Lu-Hf isotope and trace-element systematics of Mesoarchaean amphibolites, inner Ameralik fjord, southern West Greenland |
title_short |
Sm-Nd and Lu-Hf isotope and trace-element systematics of Mesoarchaean amphibolites, inner Ameralik fjord, southern West Greenland |
title_full |
Sm-Nd and Lu-Hf isotope and trace-element systematics of Mesoarchaean amphibolites, inner Ameralik fjord, southern West Greenland |
title_fullStr |
Sm-Nd and Lu-Hf isotope and trace-element systematics of Mesoarchaean amphibolites, inner Ameralik fjord, southern West Greenland |
title_full_unstemmed |
Sm-Nd and Lu-Hf isotope and trace-element systematics of Mesoarchaean amphibolites, inner Ameralik fjord, southern West Greenland |
title_sort |
sm-nd and lu-hf isotope and trace-element systematics of mesoarchaean amphibolites, inner ameralik fjord, southern west greenland |
publisher |
MINERALOGICAL SOC |
publishDate |
2015 |
url |
https://kups.ub.uni-koeln.de/39681/ |
long_lat |
ENVELOPE(-51.000,-51.000,64.117,64.117) |
geographic |
Ameralik Greenland |
geographic_facet |
Ameralik Greenland |
genre |
Ameralik Ameralik fjord Greenland North Atlantic |
genre_facet |
Ameralik Ameralik fjord Greenland North Atlantic |
op_relation |
Szilas, Kristoffer orcid:0000-0002-5541-306X , Hoffmann, J. Elis orcid:0000-0001-6670-1393 , Hansmeier, Christina, Hollis, Julie A., Muenker, Carsten, Viehmann, Sebastian orcid:0000-0001-6138-5862 and Kasper, Haino U. (2015). Sm-Nd and Lu-Hf isotope and trace-element systematics of Mesoarchaean amphibolites, inner Ameralik fjord, southern West Greenland. Mineral. Mag., 79 (4). S. 857 - 877. TWICKENHAM: MINERALOGICAL SOC. ISSN 1471-8022 |
_version_ |
1766360972596871168 |