| Titre | An abrupt extinction in the Middle Permian (Capitanian) of the Boreal Realm (Spitsbergen) and its link to anoxia and acidification |
| Auteur | Bond, D P G; Wignall, P B; Joachimski, M M; Sun, Y; Savov, I; Grasby, S E; Beauchamp, B; Blomeier, D P G |
| Source | Geological Society of America Bulletin 2015 p. 1-12, https://doi.org/10.1130/B31216.1 (Accès ouvert) |
| Année | 2015 |
| Séries alt. | Secteur des sciences de la Terre, Contribution externe 20140490 |
| Éditeur | Geological Society of America |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1130/B31216.1 |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Lat/Long OENS | 13.5000 15.0000 78.2500 77.5000 |
| Sujets | extinctions biotiques; isotopes; rapports isotopiques; rapports strontium-strontium; corrélations stratigraphiques; paléontologie; Paléozoïque; Permien |
| Illustrations | location maps; stratigraphic columns; photographs; tables |
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| Programme | Bassin de Sverdrup de l'ouest de l'Arctique, GEM2 : La géocartographie de l'énergie et des minéraux |
| Diffusé | 2015 04 14 |
| Résumé | (disponible en anglais seulement)
The controversial Capitanian (Middle Permian, 262 Ma) extinction event is only known from equatorial latitudes, and consequently its global extent is poorly
resolved. We demonstrate that there were two, severe extinctions amongst brachiopods in northern Boreal latitudes (Spitsbergen) in the Middle to Late Permian, separated by a recovery phase. New age dating of the Spitsbergen strata (belonging to the
Kapp Starostin Formation), using strontium isotopes and d13C trends and comparison with better-dated sections in Greenland, suggests that the first crisis occurred in the Capitanian. This age assignment indicates that this Middle Permian extinction
is manifested at higher latitudes. Redox proxies (pyrite framboids and trace metals) show that the Boreal crisis coincided with an intensification of oxygen depletion, implicating anoxia in the extinction scenario. The widespread and near-total loss
of carbonates across the Boreal Realm also suggests a role for acidification in the crisis. The recovery interval saw the appearance of new brachiopod and bivalve taxa alongside survivors, and an increased mollusk dominance, resulting in an
assemblage reminiscent of younger Mesozoic assemblages. The subsequent end-Permian mass extinction terminated this Late Permian radiation. |
| Résumé | (Résumé en langage clair et simple, non publié)
De nouveaux outils sont utilisés pour établir la corrélation globale des âges pour les roches sédimentaires de l'Extrême-Arctique et celles du sud
de la Chine. Cela permet une attribution plus définitive de l'âge aux roches que par le passé, qui était entravée par le manque de fossiles stratigraphiques. Ces résultats soutiennent l'effort de corrélation et de cartographie transarctiques des
roches pétrolifères potentielles. |
| GEOSCAN ID | 296016 |
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