Drift carbonate on the Canadian Shield
Carbonates occur in the drift over large areas of the Precambrian Shield in Ontario. Paleozoic carbonates were transported by glaciers from the Hudson Bay Lowland and from Manitoba. Local sources in Precambrian rocks also contribute carbonate. A carbonate line corresponding approximately to the Nipi...
Published in: | Canadian Journal of Earth Sciences |
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Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Canadian Science Publishing
1987
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Subjects: | |
Online Access: | http://dx.doi.org/10.1139/e87-036 http://www.nrcresearchpress.com/doi/pdf/10.1139/e87-036 |
Summary: | Carbonates occur in the drift over large areas of the Precambrian Shield in Ontario. Paleozoic carbonates were transported by glaciers from the Hudson Bay Lowland and from Manitoba. Local sources in Precambrian rocks also contribute carbonate. A carbonate line corresponding approximately to the Nipigon and Chapleau moraines delimits high–carbonate drift to the north and may represent a significant ice marginal position or readvance about 9500 BP.Shield drift carbonates suggest that there are potential errors in radiocarbon dating of fine organic sediment (old carbon error); that there is a relationship between the occurrence of fossil molluscs in glacial and postglacial lake deposits and drift carbonate distribution; that long-distance transport will affect drift prospecting; and that susceptibility to acidification of lakes is affected by both drift and bedrock composition. |
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