| Titre | Episodic tectonics in the Phanerozoic succession of the Canadian High Arctic and the "10-million-year flood" |
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| Auteur | Embry, A; Beauchamp, B; Dewing, K ; Dixon, J |
| Source | Circum-arctic structural events: tectonic evolution of the arctic margins and trans-arctic links with adjacent orogens; par Piepjohn, K; Strauss, JV; Reinhardt, L; McClelland, WC; Geological Society of
America, Special Paper vol. 541, 2019 p. 213-230, https://doi.org/10.1130/2018.2541(11) |
| Image |  |
| Année | 2019 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20200202 |
| Éditeur | Geological Society of America |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1130/2018.2541(11) |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Province | Territoires du Nord-Ouest |
| SNRC | 47E; 47F; 47G; 47H; 57E; 57F; 57G; 57H; 67E; 67F; 67G; 67H; 77E; 77F; 77G; 77H; 87E; 87F; 87G; 87H; 97E; 97F; 97G; 97H; 107E; 107F; 107G; 107H; 117E; 117H; 48; 58; 68; 78; 88; 98; 39; 49; 59; 69; 79; 89;
99; 560; 340; 120B; 120C; 120E; 120F; 120G; 120H; 38B; 38C; 38F; 38G; 37F; 37G |
| Lat/Long OENS | -140.0000 -56.0000 84.0000 70.0000 |
| Sujets | zones tectoniques; lithosphère; stades tectoniques; analyses stratigraphiques; Bassin de Sverdrup ; Archipel Arctique Canadien; Bassin Franklinien; Bassin de Beaufort-Mackenzie ; Nature et environnement;
Sciences et technologie; stratigraphie; Phanérozoïque |
| Illustrations | cartes de localisation; coupes; diagrammes stratigraphiques; cartes géochronologiques; tableaux |
| Diffusé | 2019 06 14 |
| Résumé | (disponible en anglais seulement)
We have identified 57 large-magnitude, sequence boundaries in the Phanerozoic succession of the Canadian High Arctic. The characteristics of the boundaries,
which include angular unconformities and significant changes in depositional and tectonic regimes across the boundaries, indicate that they were primarily generated by tectonics rather than by eustasy. Boundary frequency averages 10 million years
throughout the Phanerozoic and there is no notable variation in this frequency. It is interpreted that each boundary was generated during a tectonic episode that lasted two million years or less. Each episode began with uplift of the basin margins
and pronounced regression. This was followed by a rapid subsidence and the flooding of the basin margins. Each tectonic episode was terminated by a return to slow, long-term subsidence related to basin forming mechanisms such as thermal decay. The
tectonic episodes were separated by longer intervals of tectonic quiescence characterized by slow subsidence and basin filling. The tectonic episodes are interpreted to be the product of changes in lithospheric stress fields with uplift being related
to increased, compressional horizontal stress and the following time of rapid subsidence reflecting a decrease in such stresses or an increase in tensional stresses. Conversely, the longer intervals of tectonic quiescence would reflect relatively
stable, horizontal stress fields. The episodic changes in stress fields affecting the Canadian High Arctic throughout the Phanerozoic may be a product of intermittent, plate tectonic reorganizations that involved changes in the speed and directions
of plate movements. The longer intervals of tectonic quiescence would occur during times of quasi-equilibrium in the plate tectonic mosaic. The tectonic episodes that generated the sequence boundaries were governed by nonlinear dynamics and chaotic
behavior, and there is a one-in-10-million chance that a tectonic episode will be initiated in the Canadian High Arctic in any given year. Thus, the major transgression associated with each episode can be referred to as a "10-million-year
flood." |
| GEOSCAN ID | 326614 |
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