Post-magmatic alteration in eudialyte from the North Qoroq centre, South Greenland
The North Qoroq centre comprises a series of nested nepheline syenite intrusions and forms part of the midlate Proterozoic Gardar province of South Greenland. Within the centre fractionation has produced varied rock types ranging from augite-syenite to lujavrite, a eudialyte microsyenite. Samples of...
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Mineralogical Society of Great Britian
1997
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Online Access: | http://hdl.handle.net/10294/3077 |
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ftunivregina:oai:ourspace.uregina.ca:10294/3077 2023-10-09T21:51:56+02:00 Post-magmatic alteration in eudialyte from the North Qoroq centre, South Greenland Coulson, Ian Michael 1997-02 application/pdf http://hdl.handle.net/10294/3077 en eng Mineralogical Society of Great Britian Mineralogical Magazine 61 Coulson, I.M. (1997) Post-magmatic alteration in eudialyte from the North Qôroq centre, South Greenland. Mineralogical Magazine 61:1, 99-109. doi:10.1180/minmag.1997.061.404.10 http://hdl.handle.net/10294/3077 eudialyte zirfesite alteration metasomatism Igaliko Greenland Gardar Article 1997 ftunivregina https://doi.org/10.1180/minmag.1997.061.404.10 2023-09-16T22:13:39Z The North Qoroq centre comprises a series of nested nepheline syenite intrusions and forms part of the midlate Proterozoic Gardar province of South Greenland. Within the centre fractionation has produced varied rock types ranging from augite-syenite to lujavrite, a eudialyte microsyenite. Samples of eudialyte from the lujavrites of unit SN1B of the centre show evidence for two-stage alteration. This alteration ranges from slight modification along crystal margins to complete breakdown and replacement by new pseudomorphing phases. Modification to crystal margins is accompanied by increasing Nb and Zr contents and is related to metasomatism produced by the intrusion of younger syenite units of the North Qoroq centre. More extensive alteration is as a result of metasomatism followed by lower-temperature supergene alteration. Simplified reactions for this breakdown include eudialyte + metasomatic fluid = allanite + nepheline; eudialyte + metasomatic fluid = titanite + aegirine + mesandrite + w6hlerite; eudialyte + fluid = zirfesite + fluid. Mass balance calculations for altered compared with unaltered samples of lujavrite show that alteration took place at approximately constant volume with an overall increase in Fe (+2.41 g/100g), Si and K (+0.65 and +0.61 g/ 100g), whilst Na (-2.67 g/100g) and all trace elements, particularly La, Y, Nb and Zr (-5.6 to -166 g/ 10000g) are lost from the system. Faculty yes Article in Journal/Newspaper Greenland Igaliko oURspace - The University of Regina's Institutional Repository Greenland Mineralogical Magazine 61 404 99 109 |
institution |
Open Polar |
collection |
oURspace - The University of Regina's Institutional Repository |
op_collection_id |
ftunivregina |
language |
English |
topic |
eudialyte zirfesite alteration metasomatism Igaliko Greenland Gardar |
spellingShingle |
eudialyte zirfesite alteration metasomatism Igaliko Greenland Gardar Coulson, Ian Michael Post-magmatic alteration in eudialyte from the North Qoroq centre, South Greenland |
topic_facet |
eudialyte zirfesite alteration metasomatism Igaliko Greenland Gardar |
description |
The North Qoroq centre comprises a series of nested nepheline syenite intrusions and forms part of the midlate Proterozoic Gardar province of South Greenland. Within the centre fractionation has produced varied rock types ranging from augite-syenite to lujavrite, a eudialyte microsyenite. Samples of eudialyte from the lujavrites of unit SN1B of the centre show evidence for two-stage alteration. This alteration ranges from slight modification along crystal margins to complete breakdown and replacement by new pseudomorphing phases. Modification to crystal margins is accompanied by increasing Nb and Zr contents and is related to metasomatism produced by the intrusion of younger syenite units of the North Qoroq centre. More extensive alteration is as a result of metasomatism followed by lower-temperature supergene alteration. Simplified reactions for this breakdown include eudialyte + metasomatic fluid = allanite + nepheline; eudialyte + metasomatic fluid = titanite + aegirine + mesandrite + w6hlerite; eudialyte + fluid = zirfesite + fluid. Mass balance calculations for altered compared with unaltered samples of lujavrite show that alteration took place at approximately constant volume with an overall increase in Fe (+2.41 g/100g), Si and K (+0.65 and +0.61 g/ 100g), whilst Na (-2.67 g/100g) and all trace elements, particularly La, Y, Nb and Zr (-5.6 to -166 g/ 10000g) are lost from the system. Faculty yes |
format |
Article in Journal/Newspaper |
author |
Coulson, Ian Michael |
author_facet |
Coulson, Ian Michael |
author_sort |
Coulson, Ian Michael |
title |
Post-magmatic alteration in eudialyte from the North Qoroq centre, South Greenland |
title_short |
Post-magmatic alteration in eudialyte from the North Qoroq centre, South Greenland |
title_full |
Post-magmatic alteration in eudialyte from the North Qoroq centre, South Greenland |
title_fullStr |
Post-magmatic alteration in eudialyte from the North Qoroq centre, South Greenland |
title_full_unstemmed |
Post-magmatic alteration in eudialyte from the North Qoroq centre, South Greenland |
title_sort |
post-magmatic alteration in eudialyte from the north qoroq centre, south greenland |
publisher |
Mineralogical Society of Great Britian |
publishDate |
1997 |
url |
http://hdl.handle.net/10294/3077 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Igaliko |
genre_facet |
Greenland Igaliko |
op_relation |
Mineralogical Magazine 61 Coulson, I.M. (1997) Post-magmatic alteration in eudialyte from the North Qôroq centre, South Greenland. Mineralogical Magazine 61:1, 99-109. doi:10.1180/minmag.1997.061.404.10 http://hdl.handle.net/10294/3077 |
op_doi |
https://doi.org/10.1180/minmag.1997.061.404.10 |
container_title |
Mineralogical Magazine |
container_volume |
61 |
container_issue |
404 |
container_start_page |
99 |
op_container_end_page |
109 |
_version_ |
1779315061754429440 |