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TitreLate Quaternary paleoceanographic changes in Dixon Entrance, northwest British Columbia, Canada: evidence from the foraminiferal faunal succession
AuteurGuilbault, J -P; Patterson, R T; Thomson, R E; Barrie, J V; Conway, K M
SourceJournal of Foraminiferal Research vol. 27, no. 3, 1997 p. 151-174, https://doi.org/10.2113/gsjfr.27.3.151
LiensAbstract - Résumé
Année1997
Séries alt.Commission géologique du Canada, Contributions aux publications extérieures 1996350
ÉditeurGeoScienceWorld
Documentpublication en série
Lang.anglais
DOIhttps://doi.org/10.2113/gsjfr.27.3.151
Mediapapier; en ligne; numérique
Formatspdf
ProvinceColombie-Britannique
SNRC103J; 103K
Lat/Long OENS-134.0000 -130.0000 55.0000 54.0000
SujetsHolocène; dépôts glaciaires; biofaciès; déglaciation; assemblages fossiles; distribution de fossiles; paléoenvironnement; lithostratigraphie; océanographie; température de l'eau; Foraminifères; stratigraphie; paléontologie; Cénozoïque; Quaternaire
Illustrationssketch maps; tables; dendrograms; stratigraphic sections
ProgrammeCRSNG Conseil de recherches en sciences naturelles et en génie du Canada
Résumé(disponible en anglais seulement)
Late glacial and Holocene foraminiferal stratigraphy of 7 piston cores from Dixon Entrance on the Pacific coast of Canada yielded 11 biofacies defined in part by cluster analysis and in part by the percentage of temperate species. Temperate species are defined as those that are not reported to be living north of the southern Bering Sea. It is possible to define three phases in the latest Wisconsinan deglaciation based on the percentage of temperate species: the glacial phase with 0 to 5% temperate species, the transitional phase with 5 to 20%, and the temperate phase with more than 20%. Assemblages dominated by Epistominella vitrea and Cassidulina reniforme characterize the oldest, "glacial" deposits (14,000-12,900 BP). Younger sediments have substrate-influenced assemblages. Muddy "transitional" deposits (12,900-10,500 BP) are dominated by the same species as the glacial material, but the coarser sediments are dominated by the attached form Lobatula fletcheri. The most abundant species in muddy "temperate" deposits (<10,500 BP) is either Epistominella pacifica or Nonionella stella. Coarse sediments of the same age are numerically dominated L. fletcheri, and also contain temperate species of the genus Islandiella. Compared to Queen Charlotte Sound further south, Dixon Entrance had generally more open marine conditions due in part to the greater depth that facilitated shoreward advection of warmer and more saline deep waters as part of an intense estuarine circulation driven by glacial melt.
GEOSCAN ID208212