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TitlePostglacial Paleoceanography of Hudson Bay: Stratigraphic, Microfaunal, and Palynological Evidence
AuthorBilodeau, G; De Vernal, A; Hillaire-Marcel, C; Josenhans, H
SourceCanadian Journal of Earth Sciences vol. 27, no. 7, 1990 p. 946-963,
Alt SeriesGeological Survey of Canada, Contribution Series 12391
PublisherCanadian Science Publishing
Mediapaper; on-line; digital
File formatpdf
ProvinceNorthern offshore region
NTS44; 33M; 43P; 45; 54N; 54O; 54P; 54I; 54J; 54H; 55P; 55I; 55H; 35M
AreaHudson Bay
Lat/Long WENS -96.0000 -78.0000 64.0000 55.0000
Subjectsgeochronology; paleontology; stratigraphy; surficial geology/geomorphology; cores; paleoenvironment; biostratigraphy; fossils; glaciomarine deposits; glacial deposits; stratigraphic correlations; geophysical interpretations; seismic profiles; seismic interpretations; seismic surveys; geophysical surveys; lithostratigraphy; palynology; radiocarbon dates; radiometric dates; climatic fluctuations; climate; fossil assemblages; fossil zones; Tyrell Sea; Foraminifera; Ostracoda; Pollen; Spores; Dynocysts; Dinoflagellates; Invertebrata; Quaternary
Illustrationstables; charts; sketch maps; stratigraphic columns; seismic profiles
Released1990 07 01
AbstractCores containing representative sequences of postglacial sediments in northern and southern Hudson Bay were analyzed for their microfaunal (foraminifers and ostracods) and palynological (dinocysts, pollen, and spores) content in order to reconstruct the evolution of environments since the last glaciation.In southern Hudson Bay, the marine invasion of the Tyrrell Sea at ca. 8000BP, following the Lake Ojibway episode, was accompanied by the development of an Arctic-type microflora and microfauna indicative of a dense seasonal sea-ice cover and stratified water masses. Shortly after 8000BP, the establishment of subarctic conditions in surface waters was accompanied by more intense homogenization of water masses. Subarctic conditions have persisted throughout most of the postglacial interval despite a recent surface-water cooling.In northern Hudson Bay, micropaleontological and lithological data reveal a succession of proximal to distal glaciomarine environments characterized by low biogenic productivity, harsh Arctic conditions, and stratified water masses. An increase in dinocyst abundance and diversity, after 6000BP, indicates the establishment of cool subarctic conditions in surface waters, while foraminifer assemblages suggest intensified mixing of water masses.The micropaleontological records of northern and southern Hudson Bay reveal a strong latitudinal gradient in biogenic productivity and water mass characteristics throughout the postglacial interval. "Interglacial" conditions, established in southern Hudson Bay very shortly after it was invaded by the sea, seem to have occurred much later in northern Hudson Bay.

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