CGRG Bibliography of Canadian Geomorphology
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Author : Frechette, B.; Bouchard, M.A.; and Richards, P.J.H.
Date : 1996
Title : Polliniferous till of the Nunavik peninsula, northern Quebec
Publication : Geographie physique et Quaternaire
Issue : 50(3):
Page(s) : 331-340
Abstract
Exceptionally high pollen concentrations have been noted in till in the vicinity of the Nouveau-Quebec crater (Richard et al., 1991 ; Frechette, 1994). We have proposed as an explanation the hypothesis that till near the ice divide is polliniferous. This present hypothesis is tested in parts of the Nunavik crossed by the Payne ice divide. Close to the ice divide, till shows pollen concentrations in the order of ~31000 grains/g whereas tills at a distance eastward and westward have mean values of 8500 grains/g and 6800 grains/g respectively. Deposits near the ice divide zone of Nunavik may have escaped significant glacial erosion and thus pollen that had accumulated during previous interstadials and interglacials may have been preserved and recycled in till. Pollen spectra of till throughout Nunavik reflects only approximately the modern biogeography, ranging from herb-tundra in the north to shrub-tundra in the south. Main components analysis, has allowed comparison between till samples and neighbouring lacustrine surface sediments ; based on that comparison the pollen assemblages of the till samples have no modern analogs which suggests some shifting in the distribution of the pre-Wisconsinan bioclimatic zones.
Bibliography of Canadian Geomorphology