GEOSCAN, résultats de la recherche

Menu GEOSCAN


TitreSeismic stratigraphic framework and depositional history of a large Upper Cretaceous and Cenozoic depocenter off southwest Nova Scotia, Canada
AuteurCampbell, D C; Shimeld, J; Deptuck, M; Mosher, D C
SourceMarine and Petroleum Geology vol. 65, 2015 p. 22-42, https://doi.org/10.1016/j.marpetgeo.2015.03.016
Année2015
Séries alt.Secteur des sciences de la Terre, Contribution externe 20150156
ÉditeurElsevier
Documentpublication en série
Lang.anglais
DOIhttps://doi.org/10.1016/j.marpetgeo.2015.03.016
Mediapapier; en ligne; numérique
Formatspdf
ProvinceRégion extracotière de l'est
Lat/Long OENS -64.0000 -58.0000 46.0000 42.0000
Sujetslevés sismiques marins; profils sismiques marins; profils sismiques; marges continentales; caractéristiques sous-marines; érosion; topographie du fond océanique; topographie du fond océanique; Plate-Forme de Néo-écossaise; Crétacé; Cénozoïque
Illustrationslocation maps; stratigraphic charts; sesimic reflection profiles; geophysical images; schematic diagrams
ProgrammePreparation of a submission for an extended continental shelf in the Atlantic and Arctic Oceans under UNCLOS, Délimitation du plateau continental du Canada en vertu de la Convention des Nations Unies sur le droit de la mer (UNCLOS)
Résumé(disponible en anglais seulement)
Interpretations of the Late Cretaceous to Quaternary geological history of the North American Basin rely on a seismic and lithostratigraphic framework developed predominantly from data along the northeastern United States margin. Prior to this study, attempts to extend this framework northward to the Nova Scotia margin were hindered by correlation issues across seamounts, limitations in data coverage, and significant complications caused by widespread canyon erosion and shallow salt structures. These challenges are overcome using modern seismic reflection
data along the southwestern Nova Scotia margin, in the Shelburne sub-basin, where Upper Cretaceous through Quaternary sequences manifest four distinct phases in the interplay between down-slope and along-slope depositional and erosional processes. The first phase, spanning the Late Cretaceous to Late Eocene, is characterized by widespread periods of gully erosion interspersed with periods of pelagic and hemipelagic, carbonate-rich sedimentation. Extensive failure of upper slope regions related to the
Montagnais meteorite impact also occurred during this time. The second phase, spanning the Oligocene to Middle Miocene, is dominated by widespread erosion, deposition by gravity flow processes, and sediment re-working by bottom currents. Marked erosion and/or non-deposition along the mid- to lower slope is attributed both to down-slope and along-slope processes. The third phase, spanning the Late Miocene to Late Pliocene, is dominated by bottom current deposition including stacked sequences of giant sediment waves and large contourite drifts along the slope. The final phase, from the Late Pliocene to present, exhibits a return to predominance of down-slope gravity flows with deposition focused below the upper slope. This four phase history of depositional and erosional processes in similar to that documented south of the study area along the U.S. margin.
Résumé(Résumé en langage clair et simple, non publié)
Ce document présente la cadre stratigraphique de la fin du Crétacé jusqu'à aujourd'hui pour une grande partie de la marge continentale de la Nouvelle-Écosse. Il montre que la forme du talus continental a changé de façon importante depuis les dernières 70 millions d'années et que les glissements de terrain sous-marins et les dépôts liés aux courants océaniques profonds étaient responsables des changements observés de la forme du fond marin au fil du temps. Les principaux changements de la stratigraphie du talus peuvent être corrélés sur une vaste superficie qui s'étend vers le sud jusqu'au talus situé au large du sud-est des États-Unis et vers le nord jusqu'à la marge de Terre-Neuve.
GEOSCAN ID296842