Paleomagnetism of Carboniferous diabase dykes from Gaspé, Quebec
The reported paleomagnetic study was carried out on 53 oriented samples (156 specimens) at 10 sites in the eastern Gaspé Peninsula. All sampled geological units are composed of sub vertical diabase dykes that cut the sedimentary formations of late Early Devonian – early Middle Devonian age. The radi...
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1987
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crcansciencepubl:10.1139/e87-163 2023-12-17T10:44:59+01:00 Paleomagnetism of Carboniferous diabase dykes from Gaspé, Quebec Seguin, Maurice K. 1987 http://dx.doi.org/10.1139/e87-163 http://www.nrcresearchpress.com/doi/pdf/10.1139/e87-163 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 24, issue 8, page 1705-1714 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 1987 crcansciencepubl https://doi.org/10.1139/e87-163 2023-11-19T13:38:21Z The reported paleomagnetic study was carried out on 53 oriented samples (156 specimens) at 10 sites in the eastern Gaspé Peninsula. All sampled geological units are composed of sub vertical diabase dykes that cut the sedimentary formations of late Early Devonian – early Middle Devonian age. The radiogenic (whole-rock K/Ar) age of these and similar dykes ranges from Late Devonian to early Middle Carboniferous (mean whole rock K/Ar age = 310 Ma). Two components were isolated. The most common component, A (D = 152°, I = +41°), is normal, whereas the second component, B (D = 315°, I = −44°), is reverse. Both components may be considered as a single one; alternatively, component A may be considered slightly older than component B. Unblocking temperatures, median destructive fields, relative frequency of occurrence of the components, and various degrees of alteration are arguments favouring the first or the second situation. The case of a single component is more probable, representing an Early Carboniferous time of acquisition of remanence (thermoremanent magnetization (TRM) probably corresponding to the time of intrusion and resetting of surrounding sedimentary rocks). The corresponding paleopole position in 148°E, 11°N. This pole position is located some 25 °to the southeast of the cluster of Carboniferous poles (mainly Middle to Late Carboniferous) for the North American craton. The significance of this discrepancy is not well understood, but it is worth noting that very recent paleomagnetic results from western Newfoundland and central New Brunswick are located closer to the paleomagnetic results of this study. The age and direction of the dyke system suggest a short period of extension following the compressive pulse of the Acadian orogeny and preceding the Alleghenian orogeny. For these reasons, the dyke system is unrelated to the initial opening of the present Atlantic Ocean. Article in Journal/Newspaper Newfoundland Canadian Science Publishing (via Crossref) Canadian Journal of Earth Sciences 24 8 1705 1714 |
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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 Seguin, Maurice K. Paleomagnetism of Carboniferous diabase dykes from Gaspé, Quebec |
topic_facet |
General Earth and Planetary Sciences |
description |
The reported paleomagnetic study was carried out on 53 oriented samples (156 specimens) at 10 sites in the eastern Gaspé Peninsula. All sampled geological units are composed of sub vertical diabase dykes that cut the sedimentary formations of late Early Devonian – early Middle Devonian age. The radiogenic (whole-rock K/Ar) age of these and similar dykes ranges from Late Devonian to early Middle Carboniferous (mean whole rock K/Ar age = 310 Ma). Two components were isolated. The most common component, A (D = 152°, I = +41°), is normal, whereas the second component, B (D = 315°, I = −44°), is reverse. Both components may be considered as a single one; alternatively, component A may be considered slightly older than component B. Unblocking temperatures, median destructive fields, relative frequency of occurrence of the components, and various degrees of alteration are arguments favouring the first or the second situation. The case of a single component is more probable, representing an Early Carboniferous time of acquisition of remanence (thermoremanent magnetization (TRM) probably corresponding to the time of intrusion and resetting of surrounding sedimentary rocks). The corresponding paleopole position in 148°E, 11°N. This pole position is located some 25 °to the southeast of the cluster of Carboniferous poles (mainly Middle to Late Carboniferous) for the North American craton. The significance of this discrepancy is not well understood, but it is worth noting that very recent paleomagnetic results from western Newfoundland and central New Brunswick are located closer to the paleomagnetic results of this study. The age and direction of the dyke system suggest a short period of extension following the compressive pulse of the Acadian orogeny and preceding the Alleghenian orogeny. For these reasons, the dyke system is unrelated to the initial opening of the present Atlantic Ocean. |
format |
Article in Journal/Newspaper |
author |
Seguin, Maurice K. |
author_facet |
Seguin, Maurice K. |
author_sort |
Seguin, Maurice K. |
title |
Paleomagnetism of Carboniferous diabase dykes from Gaspé, Quebec |
title_short |
Paleomagnetism of Carboniferous diabase dykes from Gaspé, Quebec |
title_full |
Paleomagnetism of Carboniferous diabase dykes from Gaspé, Quebec |
title_fullStr |
Paleomagnetism of Carboniferous diabase dykes from Gaspé, Quebec |
title_full_unstemmed |
Paleomagnetism of Carboniferous diabase dykes from Gaspé, Quebec |
title_sort |
paleomagnetism of carboniferous diabase dykes from gaspé, quebec |
publisher |
Canadian Science Publishing |
publishDate |
1987 |
url |
http://dx.doi.org/10.1139/e87-163 http://www.nrcresearchpress.com/doi/pdf/10.1139/e87-163 |
genre |
Newfoundland |
genre_facet |
Newfoundland |
op_source |
Canadian Journal of Earth Sciences volume 24, issue 8, page 1705-1714 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e87-163 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
24 |
container_issue |
8 |
container_start_page |
1705 |
op_container_end_page |
1714 |
_version_ |
1785564668922691584 |