Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting
A lithospherically weak zone embracing the southern margin of the Greenland Archaean craton and the Ketilidian Julianehab batholith underwent repeated rifting during the interval 1350-1140 Ma, accompanying breakup of Palaeopangaea. The Gardar Province comprises the area affected by the faulting and...
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Language: | English |
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2003
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Online Access: | https://risweb.st-andrews.ac.uk/portal/en/researchoutput/magmatism-of-the-midproterozoic-gardar-province-south-greenland-chronology-petrogenesis-and-geological-setting(31c06d97-aaf2-4eec-aa2d-faefc4ac6387).html https://doi.org/10.1016/S0024-4937(03)00030-6 http://www.scopus.com/inward/record.url?scp=0038035689&partnerID=8YFLogxK |
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ftunstandrewcris:oai:risweb.st-andrews.ac.uk:publications/31c06d97-aaf2-4eec-aa2d-faefc4ac6387 2023-05-15T16:27:45+02:00 Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting Upton, B G J Emeleus, C H Heaman, L M Goodenough, K M Finch, A A 2003-05 https://risweb.st-andrews.ac.uk/portal/en/researchoutput/magmatism-of-the-midproterozoic-gardar-province-south-greenland-chronology-petrogenesis-and-geological-setting(31c06d97-aaf2-4eec-aa2d-faefc4ac6387).html https://doi.org/10.1016/S0024-4937(03)00030-6 http://www.scopus.com/inward/record.url?scp=0038035689&partnerID=8YFLogxK eng eng info:eu-repo/semantics/restrictedAccess Upton , B G J , Emeleus , C H , Heaman , L M , Goodenough , K M & Finch , A A 2003 , ' Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting ' , Lithos , vol. 68 , no. 1-2 , pp. 43-65 . https://doi.org/10.1016/S0024-4937(03)00030-6 Greenland continental rifting mesoproterozoic alkaline magmatism KETILIDIAN OROGEN ISOTOPE EVIDENCE SYENITE COMPLEX NORTH-AMERICA DYKE SWARMS RB-SR ORIGIN ROCKS RIFT GEOCHRONOLOGY article 2003 ftunstandrewcris https://doi.org/10.1016/S0024-4937(03)00030-6 2021-12-26T14:16:48Z A lithospherically weak zone embracing the southern margin of the Greenland Archaean craton and the Ketilidian Julianehab batholith underwent repeated rifting during the interval 1350-1140 Ma, accompanying breakup of Palaeopangaea. The Gardar Province comprises the area affected by the faulting and asssociated alkaline maginatism. While an estimated 2-5 km of Proterozoic cover has been eroded, rift-fill successions have been preserved in early fault-bounded basins. The orientation of dyke swarms changed from WNW-ESE to nearly NE-SW during Gardar times. The principal swarms are inferred to occupy zones of lithospheric thinning and graben development. Central-type intrusive complexes, largely of svenites and nepheline syenites, reached shallow levels. The principal magmatic evolution was from transitional olivine basalt through to phonolites. Accompanying silica-oversaturated magma generation involved greater degrees of crustal assimilation. Anorthositic xenoliths in the Gardar intrusions imply the presence of an extensive anorthositic complex at depth, regarded as an integral part of the North American Proterozoic massif anorthosite association. The most primitive Gardar basalts are themselves relatively evolved, probably as a result of olivine pyroxene fractionation during crustal underplating. The Gardar basic rocks are troctolitic with elevated Al2O3/CaO ratios: their incompatible element patterns suggest a significant input from lithospheric sources. The Ca-deficient nature of the Gardar basalts is attributed to an origin involving lithospheric mantle depleted by previous melting events. Trace element and isotopic signatures suggest considerable heterogeneity in the mantle sources which are ascribed to differential metasomatism of clinopyroxene-poor peridotite sources by small-fraction asthenospheric melts. The ultrarnafic lamprophyre/carbonatite association that recurred throughout the period is inferred to have originated from melting of metasomites deep within the lithospheric mantle. Affinities between ... Article in Journal/Newspaper Greenland University of St Andrews: Research Portal Greenland Lithos 68 1-2 43 65 |
institution |
Open Polar |
collection |
University of St Andrews: Research Portal |
op_collection_id |
ftunstandrewcris |
language |
English |
topic |
Greenland continental rifting mesoproterozoic alkaline magmatism KETILIDIAN OROGEN ISOTOPE EVIDENCE SYENITE COMPLEX NORTH-AMERICA DYKE SWARMS RB-SR ORIGIN ROCKS RIFT GEOCHRONOLOGY |
spellingShingle |
Greenland continental rifting mesoproterozoic alkaline magmatism KETILIDIAN OROGEN ISOTOPE EVIDENCE SYENITE COMPLEX NORTH-AMERICA DYKE SWARMS RB-SR ORIGIN ROCKS RIFT GEOCHRONOLOGY Upton, B G J Emeleus, C H Heaman, L M Goodenough, K M Finch, A A Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting |
topic_facet |
Greenland continental rifting mesoproterozoic alkaline magmatism KETILIDIAN OROGEN ISOTOPE EVIDENCE SYENITE COMPLEX NORTH-AMERICA DYKE SWARMS RB-SR ORIGIN ROCKS RIFT GEOCHRONOLOGY |
description |
A lithospherically weak zone embracing the southern margin of the Greenland Archaean craton and the Ketilidian Julianehab batholith underwent repeated rifting during the interval 1350-1140 Ma, accompanying breakup of Palaeopangaea. The Gardar Province comprises the area affected by the faulting and asssociated alkaline maginatism. While an estimated 2-5 km of Proterozoic cover has been eroded, rift-fill successions have been preserved in early fault-bounded basins. The orientation of dyke swarms changed from WNW-ESE to nearly NE-SW during Gardar times. The principal swarms are inferred to occupy zones of lithospheric thinning and graben development. Central-type intrusive complexes, largely of svenites and nepheline syenites, reached shallow levels. The principal magmatic evolution was from transitional olivine basalt through to phonolites. Accompanying silica-oversaturated magma generation involved greater degrees of crustal assimilation. Anorthositic xenoliths in the Gardar intrusions imply the presence of an extensive anorthositic complex at depth, regarded as an integral part of the North American Proterozoic massif anorthosite association. The most primitive Gardar basalts are themselves relatively evolved, probably as a result of olivine pyroxene fractionation during crustal underplating. The Gardar basic rocks are troctolitic with elevated Al2O3/CaO ratios: their incompatible element patterns suggest a significant input from lithospheric sources. The Ca-deficient nature of the Gardar basalts is attributed to an origin involving lithospheric mantle depleted by previous melting events. Trace element and isotopic signatures suggest considerable heterogeneity in the mantle sources which are ascribed to differential metasomatism of clinopyroxene-poor peridotite sources by small-fraction asthenospheric melts. The ultrarnafic lamprophyre/carbonatite association that recurred throughout the period is inferred to have originated from melting of metasomites deep within the lithospheric mantle. Affinities between ... |
format |
Article in Journal/Newspaper |
author |
Upton, B G J Emeleus, C H Heaman, L M Goodenough, K M Finch, A A |
author_facet |
Upton, B G J Emeleus, C H Heaman, L M Goodenough, K M Finch, A A |
author_sort |
Upton, B G J |
title |
Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting |
title_short |
Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting |
title_full |
Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting |
title_fullStr |
Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting |
title_full_unstemmed |
Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting |
title_sort |
magmatism of the mid-proterozoic gardar province, south greenland: chronology, petrogenesis and geological setting |
publishDate |
2003 |
url |
https://risweb.st-andrews.ac.uk/portal/en/researchoutput/magmatism-of-the-midproterozoic-gardar-province-south-greenland-chronology-petrogenesis-and-geological-setting(31c06d97-aaf2-4eec-aa2d-faefc4ac6387).html https://doi.org/10.1016/S0024-4937(03)00030-6 http://www.scopus.com/inward/record.url?scp=0038035689&partnerID=8YFLogxK |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland |
genre_facet |
Greenland |
op_source |
Upton , B G J , Emeleus , C H , Heaman , L M , Goodenough , K M & Finch , A A 2003 , ' Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting ' , Lithos , vol. 68 , no. 1-2 , pp. 43-65 . https://doi.org/10.1016/S0024-4937(03)00030-6 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1016/S0024-4937(03)00030-6 |
container_title |
Lithos |
container_volume |
68 |
container_issue |
1-2 |
container_start_page |
43 |
op_container_end_page |
65 |
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1766017267238174720 |