Relict blockstreams at Insteheia, Valldalen-Tafjorden, southern Norway: Their nature and Schmidt-hammer exposure age
Two small blockstreams, the first such landforms to be recorded in the mountains of Scandinavia, are described from Insteheia, a col at 910 m asl on the watershed between Valldalen and Tafjorden (Møre og Romsdal), southern Norway. Both blockstreams display morphological and sedimentological characte...
Published in: | Permafrost and Periglacial Processes |
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Language: | English |
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2017
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Online Access: | http://eprints.uwe.ac.uk/30468/ http://eprints.uwe.ac.uk/30468/1/Blockstream%20pdf.pdf https://doi.org/10.1002/ppp.1915 |
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ftuniwestengland:oai:eprints.uwe.ac.uk:30468 2023-05-15T17:57:52+02:00 Relict blockstreams at Insteheia, Valldalen-Tafjorden, southern Norway: Their nature and Schmidt-hammer exposure age Wilson, P. Matthews, J. Mourne, R. 2017-02-24 application/pdf http://eprints.uwe.ac.uk/30468/ http://eprints.uwe.ac.uk/30468/1/Blockstream%20pdf.pdf https://doi.org/10.1002/ppp.1915 en eng John Wiley & Sons http://eprints.uwe.ac.uk/30468/1/Blockstream%20pdf.pdf Wilson, P. , Matthews, J. and Mourne, R. (2017) Relict blockstreams at Insteheia, Valldalen-Tafjorden, southern Norway: Their nature and Schmidt-hammer exposure age. Permafrost and Periglacial Processes, 28 (1). pp. 286-297. ISSN 1045-6740 Available from: http://eprints.uwe.ac.uk/30468 all_rights_reserved Article NonPeerReviewed 2017 ftuniwestengland https://doi.org/10.1002/ppp.1915 2020-08-21T16:10:23Z Two small blockstreams, the first such landforms to be recorded in the mountains of Scandinavia, are described from Insteheia, a col at 910 m asl on the watershed between Valldalen and Tafjorden (Møre og Romsdal), southern Norway. Both blockstreams display morphological and sedimentological characteristics indicative of boulder accumulations that have moved downslope by means of solifluction most probably under a permafrost climatic regime. These comprise boulder preferred orientation and dip patterns; inverse grading comprising surface boulders overlying successively finer, well-sorted cobble, pebble and finegrained (sand/silt dominated) sediment layers; imbrication, with the packing of small boulders behind larger boulders; and proximity to boulder-strewn hillslopes whose constituent boulders (organised into lobes and terraces) feed downslope into the blockstreams. Schmidt-hammer exposure-ages of 7.24 to 11.17 ka indicate that the blockstreams were last active during the Younger Dryas Stadial – Holocene transition (~9.5-11.2 ka). It is inferred that blockstream development began at ~18 ka, following the Last Glacial Maximum, and lasted for ~8 ka, and that since the blockstreams became inactive fine grained material has been progressively lost as a result of snowmelt runoff. The small areal extent and relatively recent age of the blockstreams contrast with larger-scale forms of considerably greater age in the Southern Hemisphere. Article in Journal/Newspaper permafrost Permafrost and Periglacial Processes University of the West of England, Bristol: UWE Research Repository Norway Permafrost and Periglacial Processes 28 1 286 297 |
institution |
Open Polar |
collection |
University of the West of England, Bristol: UWE Research Repository |
op_collection_id |
ftuniwestengland |
language |
English |
description |
Two small blockstreams, the first such landforms to be recorded in the mountains of Scandinavia, are described from Insteheia, a col at 910 m asl on the watershed between Valldalen and Tafjorden (Møre og Romsdal), southern Norway. Both blockstreams display morphological and sedimentological characteristics indicative of boulder accumulations that have moved downslope by means of solifluction most probably under a permafrost climatic regime. These comprise boulder preferred orientation and dip patterns; inverse grading comprising surface boulders overlying successively finer, well-sorted cobble, pebble and finegrained (sand/silt dominated) sediment layers; imbrication, with the packing of small boulders behind larger boulders; and proximity to boulder-strewn hillslopes whose constituent boulders (organised into lobes and terraces) feed downslope into the blockstreams. Schmidt-hammer exposure-ages of 7.24 to 11.17 ka indicate that the blockstreams were last active during the Younger Dryas Stadial – Holocene transition (~9.5-11.2 ka). It is inferred that blockstream development began at ~18 ka, following the Last Glacial Maximum, and lasted for ~8 ka, and that since the blockstreams became inactive fine grained material has been progressively lost as a result of snowmelt runoff. The small areal extent and relatively recent age of the blockstreams contrast with larger-scale forms of considerably greater age in the Southern Hemisphere. |
format |
Article in Journal/Newspaper |
author |
Wilson, P. Matthews, J. Mourne, R. |
spellingShingle |
Wilson, P. Matthews, J. Mourne, R. Relict blockstreams at Insteheia, Valldalen-Tafjorden, southern Norway: Their nature and Schmidt-hammer exposure age |
author_facet |
Wilson, P. Matthews, J. Mourne, R. |
author_sort |
Wilson, P. |
title |
Relict blockstreams at Insteheia, Valldalen-Tafjorden, southern Norway: Their nature and Schmidt-hammer exposure age |
title_short |
Relict blockstreams at Insteheia, Valldalen-Tafjorden, southern Norway: Their nature and Schmidt-hammer exposure age |
title_full |
Relict blockstreams at Insteheia, Valldalen-Tafjorden, southern Norway: Their nature and Schmidt-hammer exposure age |
title_fullStr |
Relict blockstreams at Insteheia, Valldalen-Tafjorden, southern Norway: Their nature and Schmidt-hammer exposure age |
title_full_unstemmed |
Relict blockstreams at Insteheia, Valldalen-Tafjorden, southern Norway: Their nature and Schmidt-hammer exposure age |
title_sort |
relict blockstreams at insteheia, valldalen-tafjorden, southern norway: their nature and schmidt-hammer exposure age |
publisher |
John Wiley & Sons |
publishDate |
2017 |
url |
http://eprints.uwe.ac.uk/30468/ http://eprints.uwe.ac.uk/30468/1/Blockstream%20pdf.pdf https://doi.org/10.1002/ppp.1915 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
permafrost Permafrost and Periglacial Processes |
genre_facet |
permafrost Permafrost and Periglacial Processes |
op_relation |
http://eprints.uwe.ac.uk/30468/1/Blockstream%20pdf.pdf Wilson, P. , Matthews, J. and Mourne, R. (2017) Relict blockstreams at Insteheia, Valldalen-Tafjorden, southern Norway: Their nature and Schmidt-hammer exposure age. Permafrost and Periglacial Processes, 28 (1). pp. 286-297. ISSN 1045-6740 Available from: http://eprints.uwe.ac.uk/30468 |
op_rights |
all_rights_reserved |
op_doi |
https://doi.org/10.1002/ppp.1915 |
container_title |
Permafrost and Periglacial Processes |
container_volume |
28 |
container_issue |
1 |
container_start_page |
286 |
op_container_end_page |
297 |
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1766166373804802048 |