Younger Dryas glacial landsystems in North West Scotland:an assessment of modern analogues and palaeoclimatic implications
By explicitly linking process to form, landsystem models developed in modern environments provide powerful tools for the reconstruction of past environments from the sedimentological and geomorphological record. Some landform characteristics, however, may originate by more than one process (equifina...
Published in: | Quaternary Science Reviews |
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Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
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2006
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Online Access: | https://risweb.st-andrews.ac.uk/portal/en/researchoutput/younger-dryas-glacial-landsystems-in-north-west-scotland(57d715bb-08c2-4279-b805-f15369c0b53c).html https://doi.org/10.1016/j.quascirev.2006.02.015 |
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ftunstandrewcris:oai:risweb.st-andrews.ac.uk:publications/57d715bb-08c2-4279-b805-f15369c0b53c 2023-05-15T16:21:59+02:00 Younger Dryas glacial landsystems in North West Scotland:an assessment of modern analogues and palaeoclimatic implications Benn, Douglas I. Lukas, Sven 2006-09 https://risweb.st-andrews.ac.uk/portal/en/researchoutput/younger-dryas-glacial-landsystems-in-north-west-scotland(57d715bb-08c2-4279-b805-f15369c0b53c).html https://doi.org/10.1016/j.quascirev.2006.02.015 eng eng info:eu-repo/semantics/restrictedAccess Benn , D I & Lukas , S 2006 , ' Younger Dryas glacial landsystems in North West Scotland : an assessment of modern analogues and palaeoclimatic implications ' , Quaternary Science Reviews , vol. 25 , no. 17-18 , pp. 2390-2408 . https://doi.org/10.1016/j.quascirev.2006.02.015 ISLE-OF-SKYE LOCH-LOMOND READVANCE LAURENTIDE ICE-SHEET HUMMOCKY MORAINE TEMPERATE GLACIER SOUTHERN NORWAY SCOTTISH HIGHLANDS AIR TEMPERATURES CENTRAL-EUROPE PUSH-MORAINES article 2006 ftunstandrewcris https://doi.org/10.1016/j.quascirev.2006.02.015 2021-12-26T14:16:11Z By explicitly linking process to form, landsystem models developed in modern environments provide powerful tools for the reconstruction of past environments from the sedimentological and geomorphological record. Some landform characteristics, however, may originate by more than one process (equifinality), so although a particular depositional model may "fit" the data, it is not necessarily the correct one. Here, we critically examine the use of modern analogues to interpret glacial landforms, focusing on "hummocky moraine", a distinctive landform association consisting of numerous sharp-crested moraine mounds and ridge fragments, which occurs on many valley floors in upland Britain. Detailed studies of examples of Younger Dryas age in the North West Highlands of Scotland show that they represent ice-contact fans which have been affected to varying degrees by ice push and subglacial deformation, and that they formed at active, oscillating ice margins. The sedimentological data are inconsistent with an origin by englacial thrusting, as has been proposed for similar moraines elsewhere in upland Britain on the basis of morphological criteria. Comparison with modern glacial landsystems shows that, although aspects of "hummocky moraines" in the study area have close modern counterparts, none provides an exact analogue in all respects. This may reflect the distinctive climate of western Scotland during the Younger Dryas. Estimates of mean July temperatures in the Younger Dryas in Scotland, based on chironomid assemblages, are c. 8 C at sea-level. When combined with reconstructed equilibrium line altitudes for contemporaneous glaciers, these estimates indicate mean annual precipitation totals in the range of 2358 +/- 337 mm yr(-1) at sea-level in NW Scotland, c. 26% higher than present-day values. The implied heavy snowfall suggests that glaciers in western Scotland during the Younger Dryas were of high activity type, unlike modern glaciers in Svalbard, for example. High glacier velocities and high winter precipitation ... Article in Journal/Newspaper glacier glacier Ice Sheet Svalbard University of St Andrews: Research Portal Loch Lomond ENVELOPE(-125.746,-125.746,54.239,54.239) Norway Svalbard Quaternary Science Reviews 25 17-18 2390 2408 |
institution |
Open Polar |
collection |
University of St Andrews: Research Portal |
op_collection_id |
ftunstandrewcris |
language |
English |
topic |
ISLE-OF-SKYE LOCH-LOMOND READVANCE LAURENTIDE ICE-SHEET HUMMOCKY MORAINE TEMPERATE GLACIER SOUTHERN NORWAY SCOTTISH HIGHLANDS AIR TEMPERATURES CENTRAL-EUROPE PUSH-MORAINES |
spellingShingle |
ISLE-OF-SKYE LOCH-LOMOND READVANCE LAURENTIDE ICE-SHEET HUMMOCKY MORAINE TEMPERATE GLACIER SOUTHERN NORWAY SCOTTISH HIGHLANDS AIR TEMPERATURES CENTRAL-EUROPE PUSH-MORAINES Benn, Douglas I. Lukas, Sven Younger Dryas glacial landsystems in North West Scotland:an assessment of modern analogues and palaeoclimatic implications |
topic_facet |
ISLE-OF-SKYE LOCH-LOMOND READVANCE LAURENTIDE ICE-SHEET HUMMOCKY MORAINE TEMPERATE GLACIER SOUTHERN NORWAY SCOTTISH HIGHLANDS AIR TEMPERATURES CENTRAL-EUROPE PUSH-MORAINES |
description |
By explicitly linking process to form, landsystem models developed in modern environments provide powerful tools for the reconstruction of past environments from the sedimentological and geomorphological record. Some landform characteristics, however, may originate by more than one process (equifinality), so although a particular depositional model may "fit" the data, it is not necessarily the correct one. Here, we critically examine the use of modern analogues to interpret glacial landforms, focusing on "hummocky moraine", a distinctive landform association consisting of numerous sharp-crested moraine mounds and ridge fragments, which occurs on many valley floors in upland Britain. Detailed studies of examples of Younger Dryas age in the North West Highlands of Scotland show that they represent ice-contact fans which have been affected to varying degrees by ice push and subglacial deformation, and that they formed at active, oscillating ice margins. The sedimentological data are inconsistent with an origin by englacial thrusting, as has been proposed for similar moraines elsewhere in upland Britain on the basis of morphological criteria. Comparison with modern glacial landsystems shows that, although aspects of "hummocky moraines" in the study area have close modern counterparts, none provides an exact analogue in all respects. This may reflect the distinctive climate of western Scotland during the Younger Dryas. Estimates of mean July temperatures in the Younger Dryas in Scotland, based on chironomid assemblages, are c. 8 C at sea-level. When combined with reconstructed equilibrium line altitudes for contemporaneous glaciers, these estimates indicate mean annual precipitation totals in the range of 2358 +/- 337 mm yr(-1) at sea-level in NW Scotland, c. 26% higher than present-day values. The implied heavy snowfall suggests that glaciers in western Scotland during the Younger Dryas were of high activity type, unlike modern glaciers in Svalbard, for example. High glacier velocities and high winter precipitation ... |
format |
Article in Journal/Newspaper |
author |
Benn, Douglas I. Lukas, Sven |
author_facet |
Benn, Douglas I. Lukas, Sven |
author_sort |
Benn, Douglas I. |
title |
Younger Dryas glacial landsystems in North West Scotland:an assessment of modern analogues and palaeoclimatic implications |
title_short |
Younger Dryas glacial landsystems in North West Scotland:an assessment of modern analogues and palaeoclimatic implications |
title_full |
Younger Dryas glacial landsystems in North West Scotland:an assessment of modern analogues and palaeoclimatic implications |
title_fullStr |
Younger Dryas glacial landsystems in North West Scotland:an assessment of modern analogues and palaeoclimatic implications |
title_full_unstemmed |
Younger Dryas glacial landsystems in North West Scotland:an assessment of modern analogues and palaeoclimatic implications |
title_sort |
younger dryas glacial landsystems in north west scotland:an assessment of modern analogues and palaeoclimatic implications |
publishDate |
2006 |
url |
https://risweb.st-andrews.ac.uk/portal/en/researchoutput/younger-dryas-glacial-landsystems-in-north-west-scotland(57d715bb-08c2-4279-b805-f15369c0b53c).html https://doi.org/10.1016/j.quascirev.2006.02.015 |
long_lat |
ENVELOPE(-125.746,-125.746,54.239,54.239) |
geographic |
Loch Lomond Norway Svalbard |
geographic_facet |
Loch Lomond Norway Svalbard |
genre |
glacier glacier Ice Sheet Svalbard |
genre_facet |
glacier glacier Ice Sheet Svalbard |
op_source |
Benn , D I & Lukas , S 2006 , ' Younger Dryas glacial landsystems in North West Scotland : an assessment of modern analogues and palaeoclimatic implications ' , Quaternary Science Reviews , vol. 25 , no. 17-18 , pp. 2390-2408 . https://doi.org/10.1016/j.quascirev.2006.02.015 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1016/j.quascirev.2006.02.015 |
container_title |
Quaternary Science Reviews |
container_volume |
25 |
container_issue |
17-18 |
container_start_page |
2390 |
op_container_end_page |
2408 |
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1766009961670770688 |