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TitleA pollen record from the Agassiz Ice Cap, northern Ellesmere Island, Canada
AuthorBourgeois, J C
SourceBoreas vol. 15, no. 4, 1986 p. 345-354,
Alt SeriesEarth Sciences Sector, Contribution Series 20060716
Mediapaper; on-line; digital
File formatpdf
AreaEllesmere Island; Canada
Lat/Long WENS -80.0000 -72.0000 82.0000 81.0000
Subjectsenvironmental geology; surficial geology/geomorphology; pollen analyses; paleoenvironment; snow; test pits; environmental studies; climatology; climate, arctic; climatic fluctuations; variation trends; glaciers; ice samples; drill core analyses; pollen stratigraphy; pollen zones; Agassiz Ice Cap; Quaternary
Illustrationssketch maps; profiles; bar graphs; tables
ProgramPolar Continental Shelf Program
Released2008 01 16
AbstractA continuous pollen record from the last glacial period to 100 B.P. was obtained from an ice core drilled in 1977 near the top of the Agassiz Ice Cap. Pollen concentrations are low (c. 15-173 grains/100 I) through-out the core and exotic pollen grains (from distant sources) dominate over regional pollen grains (from Ellesmere Island). The very low concentrations during the Wisconsinan glacial period and the early Holocene are attributed to the increased distance of potential sources as most of northern North America was ice-covered or supported tundra vegetation. An increase of exotic grains (mainly birch and alder) at c. 7,600 B.P. corresponds to the period of alder migration into the Low Arctic regions. The subsequent fluctuations of exotic pollen, especially the increase at c. 3,100 B.P., are unexplained at present. Regional pollen concentrations start to increase at c. 6,100 B.P. and a maximum concentration is reached at c. 3,100 B.P. The pollen record suggests that plant migration into northern Ellesmere was limited until 6,100 B.P., then increased gradually and continued to do so for about 1,000 years after the climate had started to deteriorate at about 4,000 B.P.

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