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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ftunivsussexfig:oai:figshare.com:article/23318813 2023-06-18T03:39:17+02:00 Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada Julian Murton 2001-02-01T00:00:00Z https://figshare.com/articles/journal_contribution/Thermokarst_sediments_and_sedimentary_structures_Tuktoyaktuk_Coastlands_western_Arctic_Canada/23318813 unknown 10779/uos.23318813.v1 https://figshare.com/articles/journal_contribution/Thermokarst_sediments_and_sedimentary_structures_Tuktoyaktuk_Coastlands_western_Arctic_Canada/23318813 Copyright not evaluated Uncategorised value Text Journal contribution 2001 ftunivsussexfig 2023-06-07T23:32:25Z 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 Ice permafrost Thermokarst wedge* University of Sussex: Figshare Arctic Canada Tuktoyaktuk ENVELOPE(-133.006,-133.006,69.425,69.425) |
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University of Sussex: Figshare |
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Uncategorised value Julian Murton Thermokarst sediments and sedimentary structures, Tuktoyaktuk Coastlands, western Arctic Canada |
topic_facet |
Uncategorised value |
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 |
Julian Murton |
author_facet |
Julian Murton |
author_sort |
Julian Murton |
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 |
publishDate |
2001 |
url |
https://figshare.com/articles/journal_contribution/Thermokarst_sediments_and_sedimentary_structures_Tuktoyaktuk_Coastlands_western_Arctic_Canada/23318813 |
long_lat |
ENVELOPE(-133.006,-133.006,69.425,69.425) |
geographic |
Arctic Canada Tuktoyaktuk |
geographic_facet |
Arctic Canada Tuktoyaktuk |
genre |
Arctic Ice permafrost Thermokarst wedge* |
genre_facet |
Arctic Ice permafrost Thermokarst wedge* |
op_relation |
10779/uos.23318813.v1 https://figshare.com/articles/journal_contribution/Thermokarst_sediments_and_sedimentary_structures_Tuktoyaktuk_Coastlands_western_Arctic_Canada/23318813 |
op_rights |
Copyright not evaluated |
_version_ |
1769004055833608192 |