The late Quaternary history of Greely Fiord and its tributaries, west-central Ellesmere Island
Moraines and meltwater channels mark the limit of the last glaciation that interfingered with the sea around the perimeter of Greely Fiord and its tributaries. The extent of this ice advance was dictated predominantly by its proximity to the sea. Consequently, the large tidewater glaciers at the fio...
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Canadian Science Publishing
1990
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Online Access: | http://dx.doi.org/10.1139/e90-025 http://www.nrcresearchpress.com/doi/pdf/10.1139/e90-025 |
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crcansciencepubl:10.1139/e90-025 2024-09-15T18:04:47+00:00 The late Quaternary history of Greely Fiord and its tributaries, west-central Ellesmere Island England, John 1990 http://dx.doi.org/10.1139/e90-025 http://www.nrcresearchpress.com/doi/pdf/10.1139/e90-025 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 27, issue 2, page 255-270 ISSN 0008-4077 1480-3313 journal-article 1990 crcansciencepubl https://doi.org/10.1139/e90-025 2024-07-25T04:10:08Z Moraines and meltwater channels mark the limit of the last glaciation that interfingered with the sea around the perimeter of Greely Fiord and its tributaries. The extent of this ice advance was dictated predominantly by its proximity to the sea. Consequently, the large tidewater glaciers at the fiord heads today were so constrained by calving that they advanced only 5–10 km. Similarly, grounding-line deposits from widespread plateau ice caps also terminate just below marine limit. The most extensive outlet glaciers, which advanced 20–35 km beyond present margins, are simply those that had access to the most extensive terrain above marine limit, i.e., the northwest margin of the Agassiz Ice Cap.Forty-one new 14 C dates are presented. The onset of the last ice advance must predate marine shells collected from sediments overlying a former grounding line when sea level was 122 m higher than present. At this site, the lowermost shells collected from glaciomarine silts dated 38 070 ± 410 BP, whereas a surface sample 13 m above them dated 22 900 ± 190 BP. Although both dates may be minimum estimates, they are nonetheless associated with an ice margin that retreated only a few kilometres by 7850 BP, suggesting the maintenance of the glacioisostatic loading (and relative sea level) during the interim. Nearby, shells in growth position overlying bedrock confirm that relative sea level was > 83 m asl by 38 010 ± 410 BP (minimum age). These marine deposits lie outside the last ice limit and are not overlain by glacigenic sediments.Distal to the last ice limit, Greely Fiord was occupied by the full glacial sea, whose limit is marked by discontinuous beaches and wave-cut benches. The full glacial sea rises from 116 m north of Greely Fiord to a maximum elevation of 148 m bordering its south shore from which it descends to 112 m asl near the head of Cañon Fiord. Numerous 14 C dates on shells collected within 8 m of marine limit show that the full glacial sea remained stable from at least 8400 to 7400 BP. Several other shell ... Article in Journal/Newspaper Ellesmere Island Greely Fiord Canadian Science Publishing Canadian Journal of Earth Sciences 27 2 255 270 |
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Canadian Science Publishing |
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crcansciencepubl |
language |
English |
description |
Moraines and meltwater channels mark the limit of the last glaciation that interfingered with the sea around the perimeter of Greely Fiord and its tributaries. The extent of this ice advance was dictated predominantly by its proximity to the sea. Consequently, the large tidewater glaciers at the fiord heads today were so constrained by calving that they advanced only 5–10 km. Similarly, grounding-line deposits from widespread plateau ice caps also terminate just below marine limit. The most extensive outlet glaciers, which advanced 20–35 km beyond present margins, are simply those that had access to the most extensive terrain above marine limit, i.e., the northwest margin of the Agassiz Ice Cap.Forty-one new 14 C dates are presented. The onset of the last ice advance must predate marine shells collected from sediments overlying a former grounding line when sea level was 122 m higher than present. At this site, the lowermost shells collected from glaciomarine silts dated 38 070 ± 410 BP, whereas a surface sample 13 m above them dated 22 900 ± 190 BP. Although both dates may be minimum estimates, they are nonetheless associated with an ice margin that retreated only a few kilometres by 7850 BP, suggesting the maintenance of the glacioisostatic loading (and relative sea level) during the interim. Nearby, shells in growth position overlying bedrock confirm that relative sea level was > 83 m asl by 38 010 ± 410 BP (minimum age). These marine deposits lie outside the last ice limit and are not overlain by glacigenic sediments.Distal to the last ice limit, Greely Fiord was occupied by the full glacial sea, whose limit is marked by discontinuous beaches and wave-cut benches. The full glacial sea rises from 116 m north of Greely Fiord to a maximum elevation of 148 m bordering its south shore from which it descends to 112 m asl near the head of Cañon Fiord. Numerous 14 C dates on shells collected within 8 m of marine limit show that the full glacial sea remained stable from at least 8400 to 7400 BP. Several other shell ... |
format |
Article in Journal/Newspaper |
author |
England, John |
spellingShingle |
England, John The late Quaternary history of Greely Fiord and its tributaries, west-central Ellesmere Island |
author_facet |
England, John |
author_sort |
England, John |
title |
The late Quaternary history of Greely Fiord and its tributaries, west-central Ellesmere Island |
title_short |
The late Quaternary history of Greely Fiord and its tributaries, west-central Ellesmere Island |
title_full |
The late Quaternary history of Greely Fiord and its tributaries, west-central Ellesmere Island |
title_fullStr |
The late Quaternary history of Greely Fiord and its tributaries, west-central Ellesmere Island |
title_full_unstemmed |
The late Quaternary history of Greely Fiord and its tributaries, west-central Ellesmere Island |
title_sort |
late quaternary history of greely fiord and its tributaries, west-central ellesmere island |
publisher |
Canadian Science Publishing |
publishDate |
1990 |
url |
http://dx.doi.org/10.1139/e90-025 http://www.nrcresearchpress.com/doi/pdf/10.1139/e90-025 |
genre |
Ellesmere Island Greely Fiord |
genre_facet |
Ellesmere Island Greely Fiord |
op_source |
Canadian Journal of Earth Sciences volume 27, issue 2, page 255-270 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e90-025 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
27 |
container_issue |
2 |
container_start_page |
255 |
op_container_end_page |
270 |
_version_ |
1810442398235361280 |