POTASSIUM–ARGON DATES OF BASIC INTRUSIVE ROCKS OF THE DISTRICT OF MACKENZIE, N.W.T.
Samples were taken from diabase dykes and related contact rocks and from a differentiated intrusive body of the District of Mackenzie in the Yellowknife–Prosperous Lake area, the Lac de Gras area, the Point Lake area, and the Tree River – Coronation Gulf area. In addition, several samples were taken...
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Canadian Science Publishing
1966
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Online Access: | http://dx.doi.org/10.1139/e66-029 http://www.nrcresearchpress.com/doi/pdf/10.1139/e66-029 |
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crcansciencepubl:10.1139/e66-029 2024-09-15T18:02:51+00:00 POTASSIUM–ARGON DATES OF BASIC INTRUSIVE ROCKS OF THE DISTRICT OF MACKENZIE, N.W.T. Leech, Alice Payne 1966 http://dx.doi.org/10.1139/e66-029 http://www.nrcresearchpress.com/doi/pdf/10.1139/e66-029 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 3, issue 3, page 389-412 ISSN 0008-4077 1480-3313 journal-article 1966 crcansciencepubl https://doi.org/10.1139/e66-029 2024-07-25T04:10:06Z Samples were taken from diabase dykes and related contact rocks and from a differentiated intrusive body of the District of Mackenzie in the Yellowknife–Prosperous Lake area, the Lac de Gras area, the Point Lake area, and the Tree River – Coronation Gulf area. In addition, several samples were taken from basic intrusions of Ontario, and some of the results obtained from these are included.Radiometric dating by the potassium–argon method indicated at least four periods of diabase dyke intrusion in the Slave Province of the Precambrian shield about 2 200–2 400 m.y. ago, 1 900–2 100 m.y. ago, 1 100–1 200 m.y. ago, and 600–700 m.y. ago. Scatter in the radiometric dates prevents recognition of other possible events by use of the whole-rock method, where the age of intrusion is older than Middle Proterozoic.Chemical and petrologic studies were carried out in conjunction with the radiometric dating. Precise determination of potassium proved difficult; in most cases, a best value for each sample was selected from the results of three independent determinations. There is some suggestion of an increase in the potassium content of diabase dykes in the Canadian shield throughout Precambrian time. Alkali–silica ratios show that all of the diabase dykes studied belong to the world-wide tholeiitic magma type. Article in Journal/Newspaper Coronation Gulf Yellowknife Canadian Science Publishing Canadian Journal of Earth Sciences 3 3 389 412 |
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Open Polar |
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Canadian Science Publishing |
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crcansciencepubl |
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English |
description |
Samples were taken from diabase dykes and related contact rocks and from a differentiated intrusive body of the District of Mackenzie in the Yellowknife–Prosperous Lake area, the Lac de Gras area, the Point Lake area, and the Tree River – Coronation Gulf area. In addition, several samples were taken from basic intrusions of Ontario, and some of the results obtained from these are included.Radiometric dating by the potassium–argon method indicated at least four periods of diabase dyke intrusion in the Slave Province of the Precambrian shield about 2 200–2 400 m.y. ago, 1 900–2 100 m.y. ago, 1 100–1 200 m.y. ago, and 600–700 m.y. ago. Scatter in the radiometric dates prevents recognition of other possible events by use of the whole-rock method, where the age of intrusion is older than Middle Proterozoic.Chemical and petrologic studies were carried out in conjunction with the radiometric dating. Precise determination of potassium proved difficult; in most cases, a best value for each sample was selected from the results of three independent determinations. There is some suggestion of an increase in the potassium content of diabase dykes in the Canadian shield throughout Precambrian time. Alkali–silica ratios show that all of the diabase dykes studied belong to the world-wide tholeiitic magma type. |
format |
Article in Journal/Newspaper |
author |
Leech, Alice Payne |
spellingShingle |
Leech, Alice Payne POTASSIUM–ARGON DATES OF BASIC INTRUSIVE ROCKS OF THE DISTRICT OF MACKENZIE, N.W.T. |
author_facet |
Leech, Alice Payne |
author_sort |
Leech, Alice Payne |
title |
POTASSIUM–ARGON DATES OF BASIC INTRUSIVE ROCKS OF THE DISTRICT OF MACKENZIE, N.W.T. |
title_short |
POTASSIUM–ARGON DATES OF BASIC INTRUSIVE ROCKS OF THE DISTRICT OF MACKENZIE, N.W.T. |
title_full |
POTASSIUM–ARGON DATES OF BASIC INTRUSIVE ROCKS OF THE DISTRICT OF MACKENZIE, N.W.T. |
title_fullStr |
POTASSIUM–ARGON DATES OF BASIC INTRUSIVE ROCKS OF THE DISTRICT OF MACKENZIE, N.W.T. |
title_full_unstemmed |
POTASSIUM–ARGON DATES OF BASIC INTRUSIVE ROCKS OF THE DISTRICT OF MACKENZIE, N.W.T. |
title_sort |
potassium–argon dates of basic intrusive rocks of the district of mackenzie, n.w.t. |
publisher |
Canadian Science Publishing |
publishDate |
1966 |
url |
http://dx.doi.org/10.1139/e66-029 http://www.nrcresearchpress.com/doi/pdf/10.1139/e66-029 |
genre |
Coronation Gulf Yellowknife |
genre_facet |
Coronation Gulf Yellowknife |
op_source |
Canadian Journal of Earth Sciences volume 3, issue 3, page 389-412 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e66-029 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
3 |
container_issue |
3 |
container_start_page |
389 |
op_container_end_page |
412 |
_version_ |
1810440264470233088 |