Iapetus Ocean floor stuffed into a suture zone: xenolith Nd isotopic evidence for Dunnage-equivalent basement in central Newfoundland
Granulite-facies xenoliths from Late Jurassic alkaline lamprophyres may represent basement to the Dunnage Zone in north-central Newfoundland (Notre Dame Bay area). At 143 Ma the xenoliths had positive ε Nd values between 0.9 and 4.7. They give Nd depleted mantle model ages around 700 Ma and have tra...
Published in: | Canadian Journal of Earth Sciences |
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Online Access: | http://dx.doi.org/10.1139/e17-111 http://www.nrcresearchpress.com/doi/pdf/10.1139/e17-111 |
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crcansciencepubl:10.1139/e17-111 2023-12-17T10:44:44+01:00 Iapetus Ocean floor stuffed into a suture zone: xenolith Nd isotopic evidence for Dunnage-equivalent basement in central Newfoundland Fryer, Brian J. Greenough, John D. Owen, J. Victor 1997 http://dx.doi.org/10.1139/e17-111 http://www.nrcresearchpress.com/doi/pdf/10.1139/e17-111 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 34, issue 10, page 1392-1400 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 1997 crcansciencepubl https://doi.org/10.1139/e17-111 2023-11-19T13:39:08Z Granulite-facies xenoliths from Late Jurassic alkaline lamprophyres may represent basement to the Dunnage Zone in north-central Newfoundland (Notre Dame Bay area). At 143 Ma the xenoliths had positive ε Nd values between 0.9 and 4.7. They give Nd depleted mantle model ages around 700 Ma and have trace element and major element compositions reminiscent of oceanic arc-related intermediate volcanic and sedimentary rocks. Their positive ε Nd values and associated "young" Nd model ages argue against their representing Grenvillian crust. Similarly, Gander Zone basement to the east produced granitic rocks with strongly negative ε Nd values unlike those of the xenoliths. Positive ε Nd values for Avalonian granites indicate that the xenoliths could represent Avalon-type basement; however, there are 100–200 km of Gander and Dunnage zone rocks between the xenoiith locality and the Avalon Zone. Early orogenic volcanic rocks and some late orogenic to postorogenic granitic rocks in the central to northern portion of the Gander Zone have positive ε Nd values, consistent with extraction from a depleted mantle at the same time as material forming the xenoliths. Similarities between the xenolith chemistry and that of early orogenic (Cambrian) arc-related intermediate volcanic rocks of the Dunnage Zone indicate that the xenoliths and basement in the Notre Dame Bay area are composed of Iapetus Ocean floor relics (volcanic or volcanic-rich sedimentary rocks) stuffed into a collisional suture zone during ocean closure. Article in Journal/Newspaper Newfoundland Canadian Science Publishing (via Crossref) Notre Dame Bay ENVELOPE(-54.998,-54.998,49.750,49.750) Canadian Journal of Earth Sciences 34 10 1392 1400 |
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Open Polar |
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Canadian Science Publishing (via Crossref) |
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crcansciencepubl |
language |
English |
topic |
General Earth and Planetary Sciences |
spellingShingle |
General Earth and Planetary Sciences Fryer, Brian J. Greenough, John D. Owen, J. Victor Iapetus Ocean floor stuffed into a suture zone: xenolith Nd isotopic evidence for Dunnage-equivalent basement in central Newfoundland |
topic_facet |
General Earth and Planetary Sciences |
description |
Granulite-facies xenoliths from Late Jurassic alkaline lamprophyres may represent basement to the Dunnage Zone in north-central Newfoundland (Notre Dame Bay area). At 143 Ma the xenoliths had positive ε Nd values between 0.9 and 4.7. They give Nd depleted mantle model ages around 700 Ma and have trace element and major element compositions reminiscent of oceanic arc-related intermediate volcanic and sedimentary rocks. Their positive ε Nd values and associated "young" Nd model ages argue against their representing Grenvillian crust. Similarly, Gander Zone basement to the east produced granitic rocks with strongly negative ε Nd values unlike those of the xenoliths. Positive ε Nd values for Avalonian granites indicate that the xenoliths could represent Avalon-type basement; however, there are 100–200 km of Gander and Dunnage zone rocks between the xenoiith locality and the Avalon Zone. Early orogenic volcanic rocks and some late orogenic to postorogenic granitic rocks in the central to northern portion of the Gander Zone have positive ε Nd values, consistent with extraction from a depleted mantle at the same time as material forming the xenoliths. Similarities between the xenolith chemistry and that of early orogenic (Cambrian) arc-related intermediate volcanic rocks of the Dunnage Zone indicate that the xenoliths and basement in the Notre Dame Bay area are composed of Iapetus Ocean floor relics (volcanic or volcanic-rich sedimentary rocks) stuffed into a collisional suture zone during ocean closure. |
format |
Article in Journal/Newspaper |
author |
Fryer, Brian J. Greenough, John D. Owen, J. Victor |
author_facet |
Fryer, Brian J. Greenough, John D. Owen, J. Victor |
author_sort |
Fryer, Brian J. |
title |
Iapetus Ocean floor stuffed into a suture zone: xenolith Nd isotopic evidence for Dunnage-equivalent basement in central Newfoundland |
title_short |
Iapetus Ocean floor stuffed into a suture zone: xenolith Nd isotopic evidence for Dunnage-equivalent basement in central Newfoundland |
title_full |
Iapetus Ocean floor stuffed into a suture zone: xenolith Nd isotopic evidence for Dunnage-equivalent basement in central Newfoundland |
title_fullStr |
Iapetus Ocean floor stuffed into a suture zone: xenolith Nd isotopic evidence for Dunnage-equivalent basement in central Newfoundland |
title_full_unstemmed |
Iapetus Ocean floor stuffed into a suture zone: xenolith Nd isotopic evidence for Dunnage-equivalent basement in central Newfoundland |
title_sort |
iapetus ocean floor stuffed into a suture zone: xenolith nd isotopic evidence for dunnage-equivalent basement in central newfoundland |
publisher |
Canadian Science Publishing |
publishDate |
1997 |
url |
http://dx.doi.org/10.1139/e17-111 http://www.nrcresearchpress.com/doi/pdf/10.1139/e17-111 |
long_lat |
ENVELOPE(-54.998,-54.998,49.750,49.750) |
geographic |
Notre Dame Bay |
geographic_facet |
Notre Dame Bay |
genre |
Newfoundland |
genre_facet |
Newfoundland |
op_source |
Canadian Journal of Earth Sciences volume 34, issue 10, page 1392-1400 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e17-111 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
34 |
container_issue |
10 |
container_start_page |
1392 |
op_container_end_page |
1400 |
_version_ |
1785563502966996992 |