The first 20 years (1978-1979 to 1998–1999) of ice-wedge growth at the Illisarvik experimental drained lake site, western Arctic coast, Canada
In August 1978, a large tundra lake was drained to study the aggradation of permafrost into newly exposed lake-bottom sediments. Ice-wedge growth, which started in the first winter following drainage, had ceased in most of the lake bottom within about twelve years. The gradual cessation of thermal c...
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Online Access: | http://dx.doi.org/10.1139/e01-048 http://www.nrcresearchpress.com/doi/pdf/10.1139/e01-048 |
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crcansciencepubl:10.1139/e01-048 2024-09-15T18:11:24+00:00 The first 20 years (1978-1979 to 1998–1999) of ice-wedge growth at the Illisarvik experimental drained lake site, western Arctic coast, Canada Mackay, J Ross Burn, C R 2002 http://dx.doi.org/10.1139/e01-048 http://www.nrcresearchpress.com/doi/pdf/10.1139/e01-048 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 39, issue 1, page 95-111 ISSN 0008-4077 1480-3313 journal-article 2002 crcansciencepubl https://doi.org/10.1139/e01-048 2024-08-08T04:13:33Z In August 1978, a large tundra lake was drained to study the aggradation of permafrost into newly exposed lake-bottom sediments. Ice-wedge growth, which started in the first winter following drainage, had ceased in most of the lake bottom within about twelve years. The gradual cessation of thermal contraction cracking can be attributed to rapid vegetation growth, snow entrapment, an increase in winter ground temperatures, and a decrease in the linear coefficient of thermal contraction associated with freezethaw consolidation of the initially saturated lake-bottom sediments. The tilt and separation of markers in the active layer revealed gradual convergence towards the troughs even after ice-wedge growth had ceased. For the first few years the ice-wedge growth rate was up to 3 cm/a as determined by excavation, drilling, separation of the bottoms of benchmarks installed into permafrost, and divergence of free-floating inductance coils placed on the sides of ice wedges well below the bottom of the active layer. The vertical extent of most ice wedges was probably about 2 m, as deduced from the depths of ice-wedge cracks and the geometries of the wedge tops. Many thermal contraction cracks propagated upward to the ground surface from the tops of the ice wedges rather than downward from the ground surface. Small, upward facing, horizontal steps and vertical slickensided surfaces in permafrost on both sides of an excavated ice wedge near its top indicated that the adjacent permafrost had moved upward, relative to the wedge, from thermal expansion during the warming period. Article in Journal/Newspaper Ice permafrost Tundra wedge* Canadian Science Publishing Canadian Journal of Earth Sciences 39 1 95 111 |
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Open Polar |
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Canadian Science Publishing |
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crcansciencepubl |
language |
English |
description |
In August 1978, a large tundra lake was drained to study the aggradation of permafrost into newly exposed lake-bottom sediments. Ice-wedge growth, which started in the first winter following drainage, had ceased in most of the lake bottom within about twelve years. The gradual cessation of thermal contraction cracking can be attributed to rapid vegetation growth, snow entrapment, an increase in winter ground temperatures, and a decrease in the linear coefficient of thermal contraction associated with freezethaw consolidation of the initially saturated lake-bottom sediments. The tilt and separation of markers in the active layer revealed gradual convergence towards the troughs even after ice-wedge growth had ceased. For the first few years the ice-wedge growth rate was up to 3 cm/a as determined by excavation, drilling, separation of the bottoms of benchmarks installed into permafrost, and divergence of free-floating inductance coils placed on the sides of ice wedges well below the bottom of the active layer. The vertical extent of most ice wedges was probably about 2 m, as deduced from the depths of ice-wedge cracks and the geometries of the wedge tops. Many thermal contraction cracks propagated upward to the ground surface from the tops of the ice wedges rather than downward from the ground surface. Small, upward facing, horizontal steps and vertical slickensided surfaces in permafrost on both sides of an excavated ice wedge near its top indicated that the adjacent permafrost had moved upward, relative to the wedge, from thermal expansion during the warming period. |
format |
Article in Journal/Newspaper |
author |
Mackay, J Ross Burn, C R |
spellingShingle |
Mackay, J Ross Burn, C R The first 20 years (1978-1979 to 1998–1999) of ice-wedge growth at the Illisarvik experimental drained lake site, western Arctic coast, Canada |
author_facet |
Mackay, J Ross Burn, C R |
author_sort |
Mackay, J Ross |
title |
The first 20 years (1978-1979 to 1998–1999) of ice-wedge growth at the Illisarvik experimental drained lake site, western Arctic coast, Canada |
title_short |
The first 20 years (1978-1979 to 1998–1999) of ice-wedge growth at the Illisarvik experimental drained lake site, western Arctic coast, Canada |
title_full |
The first 20 years (1978-1979 to 1998–1999) of ice-wedge growth at the Illisarvik experimental drained lake site, western Arctic coast, Canada |
title_fullStr |
The first 20 years (1978-1979 to 1998–1999) of ice-wedge growth at the Illisarvik experimental drained lake site, western Arctic coast, Canada |
title_full_unstemmed |
The first 20 years (1978-1979 to 1998–1999) of ice-wedge growth at the Illisarvik experimental drained lake site, western Arctic coast, Canada |
title_sort |
first 20 years (1978-1979 to 1998–1999) of ice-wedge growth at the illisarvik experimental drained lake site, western arctic coast, canada |
publisher |
Canadian Science Publishing |
publishDate |
2002 |
url |
http://dx.doi.org/10.1139/e01-048 http://www.nrcresearchpress.com/doi/pdf/10.1139/e01-048 |
genre |
Ice permafrost Tundra wedge* |
genre_facet |
Ice permafrost Tundra wedge* |
op_source |
Canadian Journal of Earth Sciences volume 39, issue 1, page 95-111 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e01-048 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
39 |
container_issue |
1 |
container_start_page |
95 |
op_container_end_page |
111 |
_version_ |
1810448981698805760 |