U–Pb zircon ages from Athapuscow aulacogen, East Arm of Great Slave Lake, N.W.T., Canada
Athapuscow aulacogen is an Early Proterozoic intracratonic basin located in the East Arm of Great Slave Lake between the Slave and northwest Churchill provinces. Athapuscow aulacogen comprises three stratigraphic sequences, the Wilson Island Group, the Great Slave Supergroup, and the Et-Then Group....
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crcansciencepubl:10.1139/e84-136 2024-09-15T18:08:14+00:00 U–Pb zircon ages from Athapuscow aulacogen, East Arm of Great Slave Lake, N.W.T., Canada Bowring, S. A. Schmus, W. R. Van Hoffman, P. F. 1984 http://dx.doi.org/10.1139/e84-136 http://www.nrcresearchpress.com/doi/pdf/10.1139/e84-136 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 21, issue 11, page 1315-1324 ISSN 0008-4077 1480-3313 journal-article 1984 crcansciencepubl https://doi.org/10.1139/e84-136 2024-08-01T04:10:04Z Athapuscow aulacogen is an Early Proterozoic intracratonic basin located in the East Arm of Great Slave Lake between the Slave and northwest Churchill provinces. Athapuscow aulacogen comprises three stratigraphic sequences, the Wilson Island Group, the Great Slave Supergroup, and the Et-Then Group. New U–Pb zircon ages provide constraints on the development of the aulacogen.The Blachford Lake Intrusive Suite consists of an older alkaline phase (Hearne Channel Granite) dated at 2175 ± 7 Ma and a younger peralkaline phase (Thor Lake Syenite) dated at 2094 ± 10 Ma, confirming the suggestion that the two phases may not be related. A felsite from the Wilson Island Group has an age of 1928 ± 11 Ma. The Wilson Island Group is intruded by epizonal granites (Butte Island Intrusive Suite), one of which has an age of 1895 ± 8 Ma. The Wilson Island Group and the Butte Island Instrusive Suite are entirely allochthonous with respect to the Slave craton. Rocks of the Great Slave Supergroup overlie mylonitized Wilson Island Group rocks and both were involved in northeast-directed thrusting. The Compton laccoliths intrude rocks of the Great Slave Supergroup, postdate thrusting, and are about 1865 Ma old.The Blachford Lake Intrusive Suite is significantly older than both the rift sequence in Wopmay Orogen (ca. 1900 Ma) and the Wilson Island Group; it probably is genetically unrelated. The age of the Wilson Island Group and Butte Island Intrusive Suite is considerably younger than previous estimates and is close to the minimum age of rifting in Wopmay Orogen. The Compton laccoliths are very similar to intrusive rocks in the Great Bear Magmatic Zone of Wopmay Orogen and may be related to east-dipping subduction beneath the aulacogen.The new ages strengthen the correlations between Athapuscow aulacogen and Wopmay Orogen and suggest a link with events in the Trans-Hudson Orogen to the south. Article in Journal/Newspaper Great Slave Lake Canadian Science Publishing Canadian Journal of Earth Sciences 21 11 1315 1324 |
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Canadian Science Publishing |
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English |
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Athapuscow aulacogen is an Early Proterozoic intracratonic basin located in the East Arm of Great Slave Lake between the Slave and northwest Churchill provinces. Athapuscow aulacogen comprises three stratigraphic sequences, the Wilson Island Group, the Great Slave Supergroup, and the Et-Then Group. New U–Pb zircon ages provide constraints on the development of the aulacogen.The Blachford Lake Intrusive Suite consists of an older alkaline phase (Hearne Channel Granite) dated at 2175 ± 7 Ma and a younger peralkaline phase (Thor Lake Syenite) dated at 2094 ± 10 Ma, confirming the suggestion that the two phases may not be related. A felsite from the Wilson Island Group has an age of 1928 ± 11 Ma. The Wilson Island Group is intruded by epizonal granites (Butte Island Intrusive Suite), one of which has an age of 1895 ± 8 Ma. The Wilson Island Group and the Butte Island Instrusive Suite are entirely allochthonous with respect to the Slave craton. Rocks of the Great Slave Supergroup overlie mylonitized Wilson Island Group rocks and both were involved in northeast-directed thrusting. The Compton laccoliths intrude rocks of the Great Slave Supergroup, postdate thrusting, and are about 1865 Ma old.The Blachford Lake Intrusive Suite is significantly older than both the rift sequence in Wopmay Orogen (ca. 1900 Ma) and the Wilson Island Group; it probably is genetically unrelated. The age of the Wilson Island Group and Butte Island Intrusive Suite is considerably younger than previous estimates and is close to the minimum age of rifting in Wopmay Orogen. The Compton laccoliths are very similar to intrusive rocks in the Great Bear Magmatic Zone of Wopmay Orogen and may be related to east-dipping subduction beneath the aulacogen.The new ages strengthen the correlations between Athapuscow aulacogen and Wopmay Orogen and suggest a link with events in the Trans-Hudson Orogen to the south. |
format |
Article in Journal/Newspaper |
author |
Bowring, S. A. Schmus, W. R. Van Hoffman, P. F. |
spellingShingle |
Bowring, S. A. Schmus, W. R. Van Hoffman, P. F. U–Pb zircon ages from Athapuscow aulacogen, East Arm of Great Slave Lake, N.W.T., Canada |
author_facet |
Bowring, S. A. Schmus, W. R. Van Hoffman, P. F. |
author_sort |
Bowring, S. A. |
title |
U–Pb zircon ages from Athapuscow aulacogen, East Arm of Great Slave Lake, N.W.T., Canada |
title_short |
U–Pb zircon ages from Athapuscow aulacogen, East Arm of Great Slave Lake, N.W.T., Canada |
title_full |
U–Pb zircon ages from Athapuscow aulacogen, East Arm of Great Slave Lake, N.W.T., Canada |
title_fullStr |
U–Pb zircon ages from Athapuscow aulacogen, East Arm of Great Slave Lake, N.W.T., Canada |
title_full_unstemmed |
U–Pb zircon ages from Athapuscow aulacogen, East Arm of Great Slave Lake, N.W.T., Canada |
title_sort |
u–pb zircon ages from athapuscow aulacogen, east arm of great slave lake, n.w.t., canada |
publisher |
Canadian Science Publishing |
publishDate |
1984 |
url |
http://dx.doi.org/10.1139/e84-136 http://www.nrcresearchpress.com/doi/pdf/10.1139/e84-136 |
genre |
Great Slave Lake |
genre_facet |
Great Slave Lake |
op_source |
Canadian Journal of Earth Sciences volume 21, issue 11, page 1315-1324 ISSN 0008-4077 1480-3313 |
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http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e84-136 |
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Canadian Journal of Earth Sciences |
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21 |
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11 |
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1315 |
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1324 |
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1810445563245625344 |