3D textural evidence for the formation of ultra-high tenor precious metal bearing sulfide microdroplets in offset reefs: an extreme example from the Platinova Reef, Skaergaard Intrusion, Greenland
The Platinova Reef in the Skaergaard Intrusion, east Greenland, is an example of a type of layered-intrusion-hosted, precious metal-enriched, stratiform, disseminated sulphide deposit referred to as “offset reefs”. These typically show platinum-group element (PGE) enrichment immediately below a majo...
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ftleicesterunfig:oai:figshare.com:article/10140584 2023-05-15T16:03:57+02:00 3D textural evidence for the formation of ultra-high tenor precious metal bearing sulfide microdroplets in offset reefs: an extreme example from the Platinova Reef, Skaergaard Intrusion, Greenland David A. Holwell Stephen J. Barnes Margaux Le Vaillant Reid R. Keays Louise A. Fisher Richard Prasser 2016-04-07T00:00:00Z https://figshare.com/articles/journal_contribution/3D_textural_evidence_for_the_formation_of_ultra-high_tenor_precious_metal_bearing_sulfide_microdroplets_in_offset_reefs_an_extreme_example_from_the_Platinova_Reef_Skaergaard_Intrusion_Greenland/10140584 unknown 2381/37821 https://figshare.com/articles/journal_contribution/3D_textural_evidence_for_the_formation_of_ultra-high_tenor_precious_metal_bearing_sulfide_microdroplets_in_offset_reefs_an_extreme_example_from_the_Platinova_Reef_Skaergaard_Intrusion_Greenland/10140584 CC BY-NC-ND 4.0 CC-BY-NC-ND Uncategorized IR content Text Journal contribution 2016 ftleicesterunfig 2021-11-11T19:40:11Z The Platinova Reef in the Skaergaard Intrusion, east Greenland, is an example of a type of layered-intrusion-hosted, precious metal-enriched, stratiform, disseminated sulphide deposit referred to as “offset reefs”. These typically show platinum-group element (PGE) enrichment immediately below a major increase in the abundance of Cu-rich sulphides, with a prominent peak in Au enrichment exactly at that transition between the PGE-rich and the Cu-sulphide-rich zones. The reasons for the relative sequence of offsets in metal peaks, and the occasionally very high metal tenors have been subject to great debate. Here we use an integrated approach of high-resolution X-ray computed tomography (HRXCT), SEM, synchrotron and desktop microbeam XRF mapping, and thin section petrography to comprehensively classify the textural relations of the precious metal-bearing sulphides of the Platinova Reef as an extreme end member example of an exceedingly high tenor offset deposit. Our results show that in the zones of PGE enrichment, precious metal minerals (PMMs) are intimately associated with Cu sulphide globules, mostly located at, or close to, silicate and oxide boundaries. The textures are identical in zones enriched in Pd and Au, and thus we do not see any evidence for different processes forming the different zones. The PMM:Cu sulphide ratio in each globule varies significantly but overall the size of the globules increases from the Pd-rich, through the Au-rich, and into the Cu zone, with a significant corresponding decrease in PM tenor. As such, this records a progression of exceedingly high tenor, microdroplets of sulphide, which progressively get larger up through the section, and decrease in tenor proportionally to their size. Cumulus droplets of Cu sulphide became enriched in metals, and were trapped in situ without significant transport from their point of nucleation. The transition to larger sulphides represents a change from sulphides nucleated and trapped in situ, to larger ones that liquated from magma devoid of ... Other Non-Article Part of Journal/Newspaper East Greenland Greenland University of Leicester: Figshare Greenland |
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Uncategorized IR content David A. Holwell Stephen J. Barnes Margaux Le Vaillant Reid R. Keays Louise A. Fisher Richard Prasser 3D textural evidence for the formation of ultra-high tenor precious metal bearing sulfide microdroplets in offset reefs: an extreme example from the Platinova Reef, Skaergaard Intrusion, Greenland |
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Uncategorized IR content |
description |
The Platinova Reef in the Skaergaard Intrusion, east Greenland, is an example of a type of layered-intrusion-hosted, precious metal-enriched, stratiform, disseminated sulphide deposit referred to as “offset reefs”. These typically show platinum-group element (PGE) enrichment immediately below a major increase in the abundance of Cu-rich sulphides, with a prominent peak in Au enrichment exactly at that transition between the PGE-rich and the Cu-sulphide-rich zones. The reasons for the relative sequence of offsets in metal peaks, and the occasionally very high metal tenors have been subject to great debate. Here we use an integrated approach of high-resolution X-ray computed tomography (HRXCT), SEM, synchrotron and desktop microbeam XRF mapping, and thin section petrography to comprehensively classify the textural relations of the precious metal-bearing sulphides of the Platinova Reef as an extreme end member example of an exceedingly high tenor offset deposit. Our results show that in the zones of PGE enrichment, precious metal minerals (PMMs) are intimately associated with Cu sulphide globules, mostly located at, or close to, silicate and oxide boundaries. The textures are identical in zones enriched in Pd and Au, and thus we do not see any evidence for different processes forming the different zones. The PMM:Cu sulphide ratio in each globule varies significantly but overall the size of the globules increases from the Pd-rich, through the Au-rich, and into the Cu zone, with a significant corresponding decrease in PM tenor. As such, this records a progression of exceedingly high tenor, microdroplets of sulphide, which progressively get larger up through the section, and decrease in tenor proportionally to their size. Cumulus droplets of Cu sulphide became enriched in metals, and were trapped in situ without significant transport from their point of nucleation. The transition to larger sulphides represents a change from sulphides nucleated and trapped in situ, to larger ones that liquated from magma devoid of ... |
format |
Other Non-Article Part of Journal/Newspaper |
author |
David A. Holwell Stephen J. Barnes Margaux Le Vaillant Reid R. Keays Louise A. Fisher Richard Prasser |
author_facet |
David A. Holwell Stephen J. Barnes Margaux Le Vaillant Reid R. Keays Louise A. Fisher Richard Prasser |
author_sort |
David A. Holwell |
title |
3D textural evidence for the formation of ultra-high tenor precious metal bearing sulfide microdroplets in offset reefs: an extreme example from the Platinova Reef, Skaergaard Intrusion, Greenland |
title_short |
3D textural evidence for the formation of ultra-high tenor precious metal bearing sulfide microdroplets in offset reefs: an extreme example from the Platinova Reef, Skaergaard Intrusion, Greenland |
title_full |
3D textural evidence for the formation of ultra-high tenor precious metal bearing sulfide microdroplets in offset reefs: an extreme example from the Platinova Reef, Skaergaard Intrusion, Greenland |
title_fullStr |
3D textural evidence for the formation of ultra-high tenor precious metal bearing sulfide microdroplets in offset reefs: an extreme example from the Platinova Reef, Skaergaard Intrusion, Greenland |
title_full_unstemmed |
3D textural evidence for the formation of ultra-high tenor precious metal bearing sulfide microdroplets in offset reefs: an extreme example from the Platinova Reef, Skaergaard Intrusion, Greenland |
title_sort |
3d textural evidence for the formation of ultra-high tenor precious metal bearing sulfide microdroplets in offset reefs: an extreme example from the platinova reef, skaergaard intrusion, greenland |
publishDate |
2016 |
url |
https://figshare.com/articles/journal_contribution/3D_textural_evidence_for_the_formation_of_ultra-high_tenor_precious_metal_bearing_sulfide_microdroplets_in_offset_reefs_an_extreme_example_from_the_Platinova_Reef_Skaergaard_Intrusion_Greenland/10140584 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
East Greenland Greenland |
genre_facet |
East Greenland Greenland |
op_relation |
2381/37821 https://figshare.com/articles/journal_contribution/3D_textural_evidence_for_the_formation_of_ultra-high_tenor_precious_metal_bearing_sulfide_microdroplets_in_offset_reefs_an_extreme_example_from_the_Platinova_Reef_Skaergaard_Intrusion_Greenland/10140584 |
op_rights |
CC BY-NC-ND 4.0 |
op_rightsnorm |
CC-BY-NC-ND |
_version_ |
1766399637847015424 |