Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada
Abrupt climate warming during glacial–interglacial transitions promotes regional thermokarst activity in areas of ice-rich permafrost. The ensuing thaw-related processes of melt-out, soft-sediment deformation and resedimentation may produce widespread thermokarst sediments and sedimentary structures...
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ftunivsussex:oai:sro.sussex.ac.uk:11034 2023-07-30T03:59:41+02:00 Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada Murton, Julian B 2001-02 http://sro.sussex.ac.uk/id/eprint/11034/ https://doi.org/10.1016/S0921-8181(00)00072-2 unknown Elsevier Murton, Julian B (2001) Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada. Global and Planetary Change, 28 (1-4). pp. 175-192. ISSN 0921-8181 G0001 Geography (General) Article PeerReviewed 2001 ftunivsussex https://doi.org/10.1016/S0921-8181(00)00072-2 2023-07-11T20:08:47Z Abrupt climate warming during glacial–interglacial transitions promotes regional thermokarst activity in areas of ice-rich permafrost. The ensuing thaw-related processes of melt-out, soft-sediment deformation and resedimentation may produce widespread thermokarst sediments and sedimentary structures. Examples of the most distinctive thermokarst sediments and sedimentary structures from the Tuktoyaktuk Coastlands, western Arctic Canada, comprise: (1) soft-sediment deformation structures (thermokarst involutions) in a palaeoactive layer; (2) ice-wedge casts and composite-wedge casts; (3) peaty to sandy diamicton deposited mainly by debris flows in retrogressive thaw slumps; and (4) a basal unit of diamicton and/or impure sand in some thermokarst-basin sequences, deposited by progradation of resedimented materials in thermokarst lakes. Many of the thermokarst sediments and sedimentary structures in the Tuktoyaktuk Coastlands formed as a result of rapid climate warming during the last glacial–interglacial transition, although some continue to form at present due to local (non-climatic) factors. Identification of thermokarst sediments and sedimentary structures in the geological record requires evidence for the thaw of excess ice. Direct evidence for the former occurrence of excess ice includes: (1) ice-wedge casts; (2) composite-wedge casts; (3) lenticular platy microstructures in frost-susceptible sediment; (4) certain near-surface brecciation of frost-susceptible bedrock; and (5) ramparted depressions attributed to the decay of frost mounds. Indirect evidence for former excess ice results where thaw consolidation initiates soft-sediment deformation or gelifluction. Article in Journal/Newspaper Arctic Arctic Ice permafrost Thermokarst wedge* University of Sussex: Sussex Research Online Arctic Canada Tuktoyaktuk ENVELOPE(-133.006,-133.006,69.425,69.425) Global and Planetary Change 28 1-4 175 192 |
institution |
Open Polar |
collection |
University of Sussex: Sussex Research Online |
op_collection_id |
ftunivsussex |
language |
unknown |
topic |
G0001 Geography (General) |
spellingShingle |
G0001 Geography (General) Murton, Julian B Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada |
topic_facet |
G0001 Geography (General) |
description |
Abrupt climate warming during glacial–interglacial transitions promotes regional thermokarst activity in areas of ice-rich permafrost. The ensuing thaw-related processes of melt-out, soft-sediment deformation and resedimentation may produce widespread thermokarst sediments and sedimentary structures. Examples of the most distinctive thermokarst sediments and sedimentary structures from the Tuktoyaktuk Coastlands, western Arctic Canada, comprise: (1) soft-sediment deformation structures (thermokarst involutions) in a palaeoactive layer; (2) ice-wedge casts and composite-wedge casts; (3) peaty to sandy diamicton deposited mainly by debris flows in retrogressive thaw slumps; and (4) a basal unit of diamicton and/or impure sand in some thermokarst-basin sequences, deposited by progradation of resedimented materials in thermokarst lakes. Many of the thermokarst sediments and sedimentary structures in the Tuktoyaktuk Coastlands formed as a result of rapid climate warming during the last glacial–interglacial transition, although some continue to form at present due to local (non-climatic) factors. Identification of thermokarst sediments and sedimentary structures in the geological record requires evidence for the thaw of excess ice. Direct evidence for the former occurrence of excess ice includes: (1) ice-wedge casts; (2) composite-wedge casts; (3) lenticular platy microstructures in frost-susceptible sediment; (4) certain near-surface brecciation of frost-susceptible bedrock; and (5) ramparted depressions attributed to the decay of frost mounds. Indirect evidence for former excess ice results where thaw consolidation initiates soft-sediment deformation or gelifluction. |
format |
Article in Journal/Newspaper |
author |
Murton, Julian B |
author_facet |
Murton, Julian B |
author_sort |
Murton, Julian B |
title |
Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada |
title_short |
Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada |
title_full |
Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada |
title_fullStr |
Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada |
title_full_unstemmed |
Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada |
title_sort |
thermokarst sediments and sedimentary structures, tuktoyaktuk coastlands, western arctic canada |
publisher |
Elsevier |
publishDate |
2001 |
url |
http://sro.sussex.ac.uk/id/eprint/11034/ https://doi.org/10.1016/S0921-8181(00)00072-2 |
long_lat |
ENVELOPE(-133.006,-133.006,69.425,69.425) |
geographic |
Arctic Canada Tuktoyaktuk |
geographic_facet |
Arctic Canada Tuktoyaktuk |
genre |
Arctic Arctic Ice permafrost Thermokarst wedge* |
genre_facet |
Arctic Arctic Ice permafrost Thermokarst wedge* |
op_relation |
Murton, Julian B (2001) Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada. Global and Planetary Change, 28 (1-4). pp. 175-192. ISSN 0921-8181 |
op_doi |
https://doi.org/10.1016/S0921-8181(00)00072-2 |
container_title |
Global and Planetary Change |
container_volume |
28 |
container_issue |
1-4 |
container_start_page |
175 |
op_container_end_page |
192 |
_version_ |
1772810511739518976 |