Present and postglacial rates of uplift for glaciated northern and eastern North America derived from postglacial uplift curves
Average rates of postglacial uplift reach a maximum value of nearly 4 m 100 y −1 over southeastern Hudson Bay, and another high cell, with rates of about 2.5 m 100 y −1 , lies between Bathurst Inlet and Southampton Island. Current rates of uplift are underestimated if exponential curves are fitted s...
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1970
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Online Access: | http://dx.doi.org/10.1139/e70-069 http://www.nrcresearchpress.com/doi/pdf/10.1139/e70-069 |
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crcansciencepubl:10.1139/e70-069 2024-09-15T18:11:03+00:00 Present and postglacial rates of uplift for glaciated northern and eastern North America derived from postglacial uplift curves Andrews, J. T. 1970 http://dx.doi.org/10.1139/e70-069 http://www.nrcresearchpress.com/doi/pdf/10.1139/e70-069 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 7, issue 2, page 703-715 ISSN 0008-4077 1480-3313 journal-article 1970 crcansciencepubl https://doi.org/10.1139/e70-069 2024-07-25T04:10:06Z Average rates of postglacial uplift reach a maximum value of nearly 4 m 100 y −1 over southeastern Hudson Bay, and another high cell, with rates of about 2.5 m 100 y −1 , lies between Bathurst Inlet and Southampton Island. Current rates of uplift are underestimated if exponential curves are fitted solely to dated raised marine deposits without considering the amount of future recovery. Rates of rebound are, instead, derived from A/t where A is uplift in the first 1000 y since deglaciation, and t is time since deglaciation. For the northwest margin of the former ice sheet coefficients of determination for rate of uplift, at specific times, as a function of distance are [Formula: see text]. Maps of rates of uplift for northern and eastern North America are presented for 8000 y B.P., 6000 y B.P. and the present day. They reveal the existence of three uplift centers and show that rates of uplift declined from a maximum of 10 to 12 m 100 y −1 , immediately following deglaciation, to a current maximum of about 1.3 m 100 y −1 . Agreement is satisfactory when calculated rates of uplift are compared with those derived from geological observations, radiocarbon dates, and from water-level records. A final map shows isochrones on the uplift rate of ~1 m 100 y −1 . The rate dropped to this value about 10 000 y ago on the outer northwest and southeast coasts, whereas the value might not be reached for another 2000 y in southeastern Hudson Bay. Article in Journal/Newspaper Hudson Bay Ice Sheet Southampton Island Canadian Science Publishing Canadian Journal of Earth Sciences 7 2 703 715 |
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Canadian Science Publishing |
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crcansciencepubl |
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English |
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Average rates of postglacial uplift reach a maximum value of nearly 4 m 100 y −1 over southeastern Hudson Bay, and another high cell, with rates of about 2.5 m 100 y −1 , lies between Bathurst Inlet and Southampton Island. Current rates of uplift are underestimated if exponential curves are fitted solely to dated raised marine deposits without considering the amount of future recovery. Rates of rebound are, instead, derived from A/t where A is uplift in the first 1000 y since deglaciation, and t is time since deglaciation. For the northwest margin of the former ice sheet coefficients of determination for rate of uplift, at specific times, as a function of distance are [Formula: see text]. Maps of rates of uplift for northern and eastern North America are presented for 8000 y B.P., 6000 y B.P. and the present day. They reveal the existence of three uplift centers and show that rates of uplift declined from a maximum of 10 to 12 m 100 y −1 , immediately following deglaciation, to a current maximum of about 1.3 m 100 y −1 . Agreement is satisfactory when calculated rates of uplift are compared with those derived from geological observations, radiocarbon dates, and from water-level records. A final map shows isochrones on the uplift rate of ~1 m 100 y −1 . The rate dropped to this value about 10 000 y ago on the outer northwest and southeast coasts, whereas the value might not be reached for another 2000 y in southeastern Hudson Bay. |
format |
Article in Journal/Newspaper |
author |
Andrews, J. T. |
spellingShingle |
Andrews, J. T. Present and postglacial rates of uplift for glaciated northern and eastern North America derived from postglacial uplift curves |
author_facet |
Andrews, J. T. |
author_sort |
Andrews, J. T. |
title |
Present and postglacial rates of uplift for glaciated northern and eastern North America derived from postglacial uplift curves |
title_short |
Present and postglacial rates of uplift for glaciated northern and eastern North America derived from postglacial uplift curves |
title_full |
Present and postglacial rates of uplift for glaciated northern and eastern North America derived from postglacial uplift curves |
title_fullStr |
Present and postglacial rates of uplift for glaciated northern and eastern North America derived from postglacial uplift curves |
title_full_unstemmed |
Present and postglacial rates of uplift for glaciated northern and eastern North America derived from postglacial uplift curves |
title_sort |
present and postglacial rates of uplift for glaciated northern and eastern north america derived from postglacial uplift curves |
publisher |
Canadian Science Publishing |
publishDate |
1970 |
url |
http://dx.doi.org/10.1139/e70-069 http://www.nrcresearchpress.com/doi/pdf/10.1139/e70-069 |
genre |
Hudson Bay Ice Sheet Southampton Island |
genre_facet |
Hudson Bay Ice Sheet Southampton Island |
op_source |
Canadian Journal of Earth Sciences volume 7, issue 2, page 703-715 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e70-069 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
7 |
container_issue |
2 |
container_start_page |
703 |
op_container_end_page |
715 |
_version_ |
1810448646502612992 |