Petrology of cordierite + gedrite-bearing sodic granulite from the Grenvillian Long Range Inlier, Newfoundland
Sodium-rich, potassium-poor granulite in the Long Range Inlier contains Ab + Qtz + Crd + Bt + Opx + Ilm and either gedrite or garnet, but rarely both. The distribution of garnet in the sodic gneiss was influenced by bulk compositional controls (e.g., higher Al 2 O 3 /SiO 2 ). Textural evidence indic...
Published in: | Canadian Journal of Earth Sciences |
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1995
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crcansciencepubl:10.1139/e95-085 2023-12-17T10:44:56+01:00 Petrology of cordierite + gedrite-bearing sodic granulite from the Grenvillian Long Range Inlier, Newfoundland Owen, J.V. Greenough, J.D. 1995 http://dx.doi.org/10.1139/e95-085 http://www.nrcresearchpress.com/doi/pdf/10.1139/e95-085 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 32, issue 7, page 1035-1045 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 1995 crcansciencepubl https://doi.org/10.1139/e95-085 2023-11-19T13:38:50Z Sodium-rich, potassium-poor granulite in the Long Range Inlier contains Ab + Qtz + Crd + Bt + Opx + Ilm and either gedrite or garnet, but rarely both. The distribution of garnet in the sodic gneiss was influenced by bulk compositional controls (e.g., higher Al 2 O 3 /SiO 2 ). Textural evidence indicates that gedrite was metastable with respect to Crd + Opx during granulite-grade metamorphism. Peak metamorphic conditions are estimated to have been ~700 °C at 600 MPa; the metamorphic fluid was CO 2 rich. The preservation of pelitic (Sil + Crd + Bt + Grt + Qtz + Mc + And) layers in which K 2 O > Na 2 O suggests a sedimentary precursor for the sodic gneiss, but the granulites are more sodic and less magnesian than primary sediments recently identified as possible precursors to cordierite–orthoamphibole rocks (e.g., ultramafic-derived greywackes; evaporitic mudstones). Leucosomes tend to be more sodic (mean Na 2 O/K 2 O = 23.5) than mesosomes (mean Na 2 O/K 2 O = 17.8 m garnet-free gneiss and 1.4 m garnetiferous gneiss), so, unless migmatitic melts were fractionated, the unusual composition of the sodic gneiss cannot be attributed solely to partial melting processes. The gneiss is interpreted to be derived from a weathered greywacke. Article in Journal/Newspaper Newfoundland Canadian Science Publishing (via Crossref) Canadian Journal of Earth Sciences 32 7 1035 1045 |
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Open Polar |
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Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
General Earth and Planetary Sciences |
spellingShingle |
General Earth and Planetary Sciences Owen, J.V. Greenough, J.D. Petrology of cordierite + gedrite-bearing sodic granulite from the Grenvillian Long Range Inlier, Newfoundland |
topic_facet |
General Earth and Planetary Sciences |
description |
Sodium-rich, potassium-poor granulite in the Long Range Inlier contains Ab + Qtz + Crd + Bt + Opx + Ilm and either gedrite or garnet, but rarely both. The distribution of garnet in the sodic gneiss was influenced by bulk compositional controls (e.g., higher Al 2 O 3 /SiO 2 ). Textural evidence indicates that gedrite was metastable with respect to Crd + Opx during granulite-grade metamorphism. Peak metamorphic conditions are estimated to have been ~700 °C at 600 MPa; the metamorphic fluid was CO 2 rich. The preservation of pelitic (Sil + Crd + Bt + Grt + Qtz + Mc + And) layers in which K 2 O > Na 2 O suggests a sedimentary precursor for the sodic gneiss, but the granulites are more sodic and less magnesian than primary sediments recently identified as possible precursors to cordierite–orthoamphibole rocks (e.g., ultramafic-derived greywackes; evaporitic mudstones). Leucosomes tend to be more sodic (mean Na 2 O/K 2 O = 23.5) than mesosomes (mean Na 2 O/K 2 O = 17.8 m garnet-free gneiss and 1.4 m garnetiferous gneiss), so, unless migmatitic melts were fractionated, the unusual composition of the sodic gneiss cannot be attributed solely to partial melting processes. The gneiss is interpreted to be derived from a weathered greywacke. |
format |
Article in Journal/Newspaper |
author |
Owen, J.V. Greenough, J.D. |
author_facet |
Owen, J.V. Greenough, J.D. |
author_sort |
Owen, J.V. |
title |
Petrology of cordierite + gedrite-bearing sodic granulite from the Grenvillian Long Range Inlier, Newfoundland |
title_short |
Petrology of cordierite + gedrite-bearing sodic granulite from the Grenvillian Long Range Inlier, Newfoundland |
title_full |
Petrology of cordierite + gedrite-bearing sodic granulite from the Grenvillian Long Range Inlier, Newfoundland |
title_fullStr |
Petrology of cordierite + gedrite-bearing sodic granulite from the Grenvillian Long Range Inlier, Newfoundland |
title_full_unstemmed |
Petrology of cordierite + gedrite-bearing sodic granulite from the Grenvillian Long Range Inlier, Newfoundland |
title_sort |
petrology of cordierite + gedrite-bearing sodic granulite from the grenvillian long range inlier, newfoundland |
publisher |
Canadian Science Publishing |
publishDate |
1995 |
url |
http://dx.doi.org/10.1139/e95-085 http://www.nrcresearchpress.com/doi/pdf/10.1139/e95-085 |
genre |
Newfoundland |
genre_facet |
Newfoundland |
op_source |
Canadian Journal of Earth Sciences volume 32, issue 7, page 1035-1045 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e95-085 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
32 |
container_issue |
7 |
container_start_page |
1035 |
op_container_end_page |
1045 |
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1785564569540755456 |