Platinum-group mineralization at the margin of the Skaergaard intrusion, East Greenland
This is the final version of the article. Available from Springer Verlag via the DOI in this record. Two occurrences of platinum-group elements (PGEs) along the northern margin of the Skaergaard intrusion include a sulfide-bearing gabbro with slightly less than 1 ppm PGE + Au and a clinopyroxene-act...
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Online Access: | http://hdl.handle.net/10871/25197 https://doi.org/10.1007/s00126-016-0707-3 |
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ftunivexeter:oai:ore.exeter.ac.uk:10871/25197 2024-09-15T18:04:22+00:00 Platinum-group mineralization at the margin of the Skaergaard intrusion, East Greenland Andersen, JCO Rollinson, GK McDonald, I Tegner, C Lesher, CE 2017 http://hdl.handle.net/10871/25197 https://doi.org/10.1007/s00126-016-0707-3 en eng Springer Verlag for Society for Geology Applied to Mineral Deposits Published online 10 January 2017 doi:10.1007/s00126-016-0707-3 http://hdl.handle.net/10871/25197 0026-4598 Mineralium Deposita © The Author(s) 2017. Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Skaergaard intrusion Platinum-group elements Greenland Article 2017 ftunivexeter https://doi.org/10.1007/s00126-016-0707-3 2024-07-29T03:24:15Z This is the final version of the article. Available from Springer Verlag via the DOI in this record. Two occurrences of platinum-group elements (PGEs) along the northern margin of the Skaergaard intrusion include a sulfide-bearing gabbro with slightly less than 1 ppm PGE + Au and a clinopyroxene-actinolite-plagioclase-biotite-ilmenite schist with 16 vol% sulfide and 1.8 ppm PGE + Au. Both have assemblages of pyrrhotite, pentlandite, and chalcopyrite typical for orthomagmatic sulfides. Matching platinum-group mineral assemblages with sperrylite (PtAs2), kotulskite (Pd(Bi,Te)1–2), froodite (PdBi2), michenerite (PdBiTe), and electrum (Au,Ag) suggest a common origin. Petrological and geochemical similarities suggest that the occurrences are related to the Skaergaard intrusion. The Marginal Border Series locally displays Ni depletion consistent with sulfide fractionation, and the PGE fractionation trends of the occurrences are systematically enriched by 10–50 times over the chilled margin. The PGE can be explained by sulfide-silicate immiscibility in the Skaergaard magma with R factors of 110–220. Nickel depletion in olivine suggests that the process occurred within the host cumulate, and the low R factors require little sulfide mobility. The sulfide assemblages are different to the chalcopyrite-bornite-digenite assemblage found in the Skaergaard Layered Series and Platinova Reef. These differences can be explained by the early formation of sulfide melt, while magmatic differentiation or sulfur loss caused the unusual sulfide assemblage within the Layered Series. The PGEs indicate that the sulfides formed from the Skaergaard magma. The sulfides and PGEs could not have formed from the nearby Watkins Fjord wehrlite intrusion, which is nearly barren in sulfide. We suggest that silicate-sulfide immiscibility led to PGE concentration where the Skaergaard magma became contaminated with material from the Archean basement. The authors are grateful for logistical support from Platina Resources Ltd., Geological Survey of ... Article in Journal/Newspaper East Greenland Greenland University of Exeter: Open Research Exeter (ORE) Mineralium Deposita 52 6 929 942 |
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Open Polar |
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University of Exeter: Open Research Exeter (ORE) |
op_collection_id |
ftunivexeter |
language |
English |
topic |
Skaergaard intrusion Platinum-group elements Greenland |
spellingShingle |
Skaergaard intrusion Platinum-group elements Greenland Andersen, JCO Rollinson, GK McDonald, I Tegner, C Lesher, CE Platinum-group mineralization at the margin of the Skaergaard intrusion, East Greenland |
topic_facet |
Skaergaard intrusion Platinum-group elements Greenland |
description |
This is the final version of the article. Available from Springer Verlag via the DOI in this record. Two occurrences of platinum-group elements (PGEs) along the northern margin of the Skaergaard intrusion include a sulfide-bearing gabbro with slightly less than 1 ppm PGE + Au and a clinopyroxene-actinolite-plagioclase-biotite-ilmenite schist with 16 vol% sulfide and 1.8 ppm PGE + Au. Both have assemblages of pyrrhotite, pentlandite, and chalcopyrite typical for orthomagmatic sulfides. Matching platinum-group mineral assemblages with sperrylite (PtAs2), kotulskite (Pd(Bi,Te)1–2), froodite (PdBi2), michenerite (PdBiTe), and electrum (Au,Ag) suggest a common origin. Petrological and geochemical similarities suggest that the occurrences are related to the Skaergaard intrusion. The Marginal Border Series locally displays Ni depletion consistent with sulfide fractionation, and the PGE fractionation trends of the occurrences are systematically enriched by 10–50 times over the chilled margin. The PGE can be explained by sulfide-silicate immiscibility in the Skaergaard magma with R factors of 110–220. Nickel depletion in olivine suggests that the process occurred within the host cumulate, and the low R factors require little sulfide mobility. The sulfide assemblages are different to the chalcopyrite-bornite-digenite assemblage found in the Skaergaard Layered Series and Platinova Reef. These differences can be explained by the early formation of sulfide melt, while magmatic differentiation or sulfur loss caused the unusual sulfide assemblage within the Layered Series. The PGEs indicate that the sulfides formed from the Skaergaard magma. The sulfides and PGEs could not have formed from the nearby Watkins Fjord wehrlite intrusion, which is nearly barren in sulfide. We suggest that silicate-sulfide immiscibility led to PGE concentration where the Skaergaard magma became contaminated with material from the Archean basement. The authors are grateful for logistical support from Platina Resources Ltd., Geological Survey of ... |
format |
Article in Journal/Newspaper |
author |
Andersen, JCO Rollinson, GK McDonald, I Tegner, C Lesher, CE |
author_facet |
Andersen, JCO Rollinson, GK McDonald, I Tegner, C Lesher, CE |
author_sort |
Andersen, JCO |
title |
Platinum-group mineralization at the margin of the Skaergaard intrusion, East Greenland |
title_short |
Platinum-group mineralization at the margin of the Skaergaard intrusion, East Greenland |
title_full |
Platinum-group mineralization at the margin of the Skaergaard intrusion, East Greenland |
title_fullStr |
Platinum-group mineralization at the margin of the Skaergaard intrusion, East Greenland |
title_full_unstemmed |
Platinum-group mineralization at the margin of the Skaergaard intrusion, East Greenland |
title_sort |
platinum-group mineralization at the margin of the skaergaard intrusion, east greenland |
publisher |
Springer Verlag for Society for Geology Applied to Mineral Deposits |
publishDate |
2017 |
url |
http://hdl.handle.net/10871/25197 https://doi.org/10.1007/s00126-016-0707-3 |
genre |
East Greenland Greenland |
genre_facet |
East Greenland Greenland |
op_relation |
Published online 10 January 2017 doi:10.1007/s00126-016-0707-3 http://hdl.handle.net/10871/25197 0026-4598 Mineralium Deposita |
op_rights |
© The Author(s) 2017. Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. |
op_doi |
https://doi.org/10.1007/s00126-016-0707-3 |
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942 |
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