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TitreCenomanian to Santonian Radiolarian Biostratigraphy, Carbon Isotope Stratigraphy and Paleoenvironments of the Sverdrup Basin, Ellef Ringnes Island, Nunavut, Canada
AuteurPugh, A T; Schroder-Adams, C J; Carter, E S; Herrle, J O; Galloway, J M; Haggart, J W; Andrews, J L; Hatsukano, K
SourcePalaeogeography, Palaeoclimatology, Palaeoecology vol. 413, 2014 p. 101-122, https://doi.org/10.1016/j.palaeo.2014.06.010
Année2014
Séries alt.Secteur des sciences de la Terre, Contribution externe 20130449
ÉditeurElsevier
Documentpublication en série
Lang.anglais
DOIhttps://doi.org/10.1016/j.palaeo.2014.06.010
Mediapapier; numérique; en ligne
Formatspdf
ProvinceNunavut
SNRC69C/16; 69D/13; 69E/04; 69F/01
Lat/Long OENS-101.0000 -99.0000 78.2500 77.7500
Sujetscénomanien; Santonien; distribution de fossiles; fossiles; assemblages fossiles; biostratigraphie; paléoenvironnement; isotopes de carbone; lithostratigraphie; Bassin de Sverdrup ; paléontologie; géochronologie; stratigraphie; géochimie; Mésozoïque; Crétacé
Illustrationslocation maps; photographs; stratigraphic sections; tables
ProgrammeBassin sédimentaire Sverdrup, GEM : La géocartographie de l'énergie et des minéraux
Résumé(disponible en anglais seulement)
An upper Albian to Santonian sedimentary record on Ellef Ringnes Island, Canadian Arctic Archipelago, records variable paleoenvironmental conditions within the Cretaceous Polar Sea and Sverdrup Basin. The upper Albian to lower Cenomanian uppermost Christopher and Hassel formations represent a regressive system tract from offshore to shoreface/terrestrial paleoenvironments. The upper Cenomanian to Santonian shales of the Kanguk Formation signify a distal central basin setting controlled by increased subsidence and high global sea levels. Siliceous pelagic faunas and floras dominate the basin and herein, a new radiolarian zonation for the Polar Sea is proposed. Alternating diversity and abundance patterns are interpreted as a response to sea-level controlled productivity systems. Transgressive phases correspond to low diversity shallow dwelling radiolarian taxa with an expanded Oxygen Minimum Zone (OMZ); regressive phases are coupled with radiolarian radiations of deeper dwelling species and a depressed OMZ. The upper Cenomanian to Turonian was marked by increased preservation of marine-type organic matter and organic carbon isotope excursions indicate the presence of the Oceanic Anoxic Event 2 (OAE 2) at the base of the Kanguk Formation. Rock Eval data suggest that an increasing terrestrial influence prevailed during the Coniacian to Campanian time covering the OAE 3. Benthic environments are dominated by anoxic conditions, as suggested by the near lack of benthic foraminifera and extensive intervals of fine platy shale. Only the upper Coniacian records a return to dysoxic benthic conditions. Radiolarian faunal comparisons to more southern localities suggest migration routes from the east through narrow North Atlantic pathways and from the Pacific through the Alaskan-Asian Pathway.
Résumé(Résumé en langage clair et simple, non publié)
Nous avons utilisé des microfossiles (radiolaires), des signatures géochimiques élémentaires et organiques, et les isotopes du carbone préservés dans une section de roches du Crétacé supérieur sur l'île Ellef Ringnes au Nunavut (Canada) pour reconstruire l'histoire paléo-environnementale du bassin de Sverdrup et obtenir un cadre stratigraphique pour ces roches.
GEOSCAN ID293593