Paleomagnetism and U–Pb geochronology of the Clarence Head dykes, Arctic Canada: orthogonal emplacement of mafic dykes in a large igneous province
The north–south-trending Clarence Head dyke swarm, located on Devon and Ellesmere Islands in the Canadian High Arctic, has a trend orthogonal to that of the Neoproterozoic Franklin swarm that surrounds it. The Clarence Head dykes are dated by the U–Pb method on baddeleyite to between 716 ± 1 and 713...
Published in: | Canadian Journal of Earth Sciences |
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crcansciencepubl:10.1139/e09-011 2024-09-09T19:23:44+00:00 Paleomagnetism and U–Pb geochronology of the Clarence Head dykes, Arctic Canada: orthogonal emplacement of mafic dykes in a large igneous province Denyszyn, Steven W. Davis, Don W. Halls, Henry C. Davis, Bill 2009 http://dx.doi.org/10.1139/e09-011 http://www.nrcresearchpress.com/doi/full-xml/10.1139/E09-011 http://www.nrcresearchpress.com/doi/pdf/10.1139/E09-011 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 46, issue 3, page 155-167 ISSN 0008-4077 1480-3313 journal-article 2009 crcansciencepubl https://doi.org/10.1139/e09-011 2024-08-01T04:10:04Z The north–south-trending Clarence Head dyke swarm, located on Devon and Ellesmere Islands in the Canadian High Arctic, has a trend orthogonal to that of the Neoproterozoic Franklin swarm that surrounds it. The Clarence Head dykes are dated by the U–Pb method on baddeleyite to between 716 ± 1 and 713 ± 1 Ma, ages apparently younger than, but within the published age range of, the Franklin dykes. Alpha recoil in baddeleyite is considered as a possible explanation for the difference in ages, but a comparison of the U–Pb ages of grains of equal size from both swarms suggests that recoil distances in baddeleyite are lower than those in zircon and that the Clarence Head dykes are indeed a distinctly younger event within the period of Franklin magmatism. The Clarence Head dykes represent a large swarm tangential to, and cogenetic with, a giant radiating dyke swarm ∼800 km from the indicated source. The preferred mechanism for the emplacement of the Clarence Head dykes is the exploitation of concentric zones of extension around a depleting and collapsing plume source. While the paleomagnetism of most Clarence Head dykes agrees with that of the Franklin dykes, two dykes have anomalous remanence directions, interpreted to be a chemical remanent magnetization carried by pyrrhotite. The pyrrhotite was likely deposited from fluids mobilized southward from the Devonian Ellesmerian Orogeny to the north that used the interiors of the dykes as conduits and precipitated pyrrhotite en route. Article in Journal/Newspaper Arctic Canadian Science Publishing Arctic Canada Clarence Head ENVELOPE(-77.781,-77.781,76.785,76.785) Canadian Journal of Earth Sciences 46 3 155 167 |
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Open Polar |
collection |
Canadian Science Publishing |
op_collection_id |
crcansciencepubl |
language |
English |
description |
The north–south-trending Clarence Head dyke swarm, located on Devon and Ellesmere Islands in the Canadian High Arctic, has a trend orthogonal to that of the Neoproterozoic Franklin swarm that surrounds it. The Clarence Head dykes are dated by the U–Pb method on baddeleyite to between 716 ± 1 and 713 ± 1 Ma, ages apparently younger than, but within the published age range of, the Franklin dykes. Alpha recoil in baddeleyite is considered as a possible explanation for the difference in ages, but a comparison of the U–Pb ages of grains of equal size from both swarms suggests that recoil distances in baddeleyite are lower than those in zircon and that the Clarence Head dykes are indeed a distinctly younger event within the period of Franklin magmatism. The Clarence Head dykes represent a large swarm tangential to, and cogenetic with, a giant radiating dyke swarm ∼800 km from the indicated source. The preferred mechanism for the emplacement of the Clarence Head dykes is the exploitation of concentric zones of extension around a depleting and collapsing plume source. While the paleomagnetism of most Clarence Head dykes agrees with that of the Franklin dykes, two dykes have anomalous remanence directions, interpreted to be a chemical remanent magnetization carried by pyrrhotite. The pyrrhotite was likely deposited from fluids mobilized southward from the Devonian Ellesmerian Orogeny to the north that used the interiors of the dykes as conduits and precipitated pyrrhotite en route. |
author2 |
Davis, Bill |
format |
Article in Journal/Newspaper |
author |
Denyszyn, Steven W. Davis, Don W. Halls, Henry C. |
spellingShingle |
Denyszyn, Steven W. Davis, Don W. Halls, Henry C. Paleomagnetism and U–Pb geochronology of the Clarence Head dykes, Arctic Canada: orthogonal emplacement of mafic dykes in a large igneous province |
author_facet |
Denyszyn, Steven W. Davis, Don W. Halls, Henry C. |
author_sort |
Denyszyn, Steven W. |
title |
Paleomagnetism and U–Pb geochronology of the Clarence Head dykes, Arctic Canada: orthogonal emplacement of mafic dykes in a large igneous province |
title_short |
Paleomagnetism and U–Pb geochronology of the Clarence Head dykes, Arctic Canada: orthogonal emplacement of mafic dykes in a large igneous province |
title_full |
Paleomagnetism and U–Pb geochronology of the Clarence Head dykes, Arctic Canada: orthogonal emplacement of mafic dykes in a large igneous province |
title_fullStr |
Paleomagnetism and U–Pb geochronology of the Clarence Head dykes, Arctic Canada: orthogonal emplacement of mafic dykes in a large igneous province |
title_full_unstemmed |
Paleomagnetism and U–Pb geochronology of the Clarence Head dykes, Arctic Canada: orthogonal emplacement of mafic dykes in a large igneous province |
title_sort |
paleomagnetism and u–pb geochronology of the clarence head dykes, arctic canada: orthogonal emplacement of mafic dykes in a large igneous province |
publisher |
Canadian Science Publishing |
publishDate |
2009 |
url |
http://dx.doi.org/10.1139/e09-011 http://www.nrcresearchpress.com/doi/full-xml/10.1139/E09-011 http://www.nrcresearchpress.com/doi/pdf/10.1139/E09-011 |
long_lat |
ENVELOPE(-77.781,-77.781,76.785,76.785) |
geographic |
Arctic Canada Clarence Head |
geographic_facet |
Arctic Canada Clarence Head |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
Canadian Journal of Earth Sciences volume 46, issue 3, page 155-167 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e09-011 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
46 |
container_issue |
3 |
container_start_page |
155 |
op_container_end_page |
167 |
_version_ |
1809893721381011456 |