Constraining the chronology of the Late Wisconsinan retreat of the Laurentide Ice Sheet from western Canada using luminescence ages from postglacial aeolian dune sequences
Optically stimulated luminescence (OSL) dating of quartz extracts from postglacial aeolian dunes from central Alberta in western Canada points to a landscape that was free of ice as early as 15 ka. Data from profiles where multiple ages have been obtained indicate an increase in depositional age wit...
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ftutahsudc:oai:digitalcommons.usu.edu:geology_facpub-1264 2023-05-15T16:40:07+02:00 Constraining the chronology of the Late Wisconsinan retreat of the Laurentide Ice Sheet from western Canada using luminescence ages from postglacial aeolian dune sequences Munyikwa, K. Feathers, J. Rittenour, Tammy M. Shrimpton, H. 2011-01-01T08:00:00Z https://digitalcommons.usu.edu/geology_facpub/265 unknown Hosted by Utah State University Libraries https://digitalcommons.usu.edu/geology_facpub/265 Copyright for this work is held by the author. Transmission or reproduction of materials protected by copyright beyond that allowed by fair use requires the written permission of the copyright owners. Works not in the public domain cannot be commercially exploited without permission of the copyright owner. Responsibility for any use rests exclusively with the user. For more information contact the Institutional Repository Librarian at digitalcommons@usu.edu. PDM Geosciences Faculty Publications chronology Wisconsinan Laurentide Ice Sheet luminescence postglacial Earth Sciences Geology Physical Sciences and Mathematics text 2011 ftutahsudc 2022-03-07T22:18:22Z Optically stimulated luminescence (OSL) dating of quartz extracts from postglacial aeolian dunes from central Alberta in western Canada points to a landscape that was free of ice as early as 15 ka. Data from profiles where multiple ages have been obtained indicate an increase in depositional age with depth, suggesting that older aeolian sands underlie the dated sequences. The OSL ages present plausible minimum age constraints for the retreat of the Laurentide Ice Sheet (LIS) towards the end of the Late Wisconsinan glaciation. Previous reconstructions of the LIS recession have relied on radiocarbon chronologies, despite the scarcity of contemporaneous radiocarbon-bearing material for large parts of western Canada. While the OSL chronology may be deemed concordant with ice sheet margin retreat models determined using radiocarbon data, there appears to be a systematic lag in the radiocarbon ages which may reflect that aeolian activity is initiated prior to the proliferation of organic material. The OSL chronology reported in this study does not preclude the emergence of a wide deglacial corridor between the LIS and the Cordilleran Ice Sheet by 15 ka or earlier. The possibility of such a passage would resuscitate the notion of an ice-free corridor that appeared early enough to afford the first peoples of the Americas a navigable inland migratory passage from Beringia to south of the North American ice sheets. More broadly, the corridor would also have allowed genetic exchanges between the Beringian refugium and the American middle and low latitudes. Text Ice Sheet Beringia Utah State University: DigitalCommons@USU Canada The Corridor ENVELOPE(78.139,78.139,-68.582,-68.582) |
institution |
Open Polar |
collection |
Utah State University: DigitalCommons@USU |
op_collection_id |
ftutahsudc |
language |
unknown |
topic |
chronology Wisconsinan Laurentide Ice Sheet luminescence postglacial Earth Sciences Geology Physical Sciences and Mathematics |
spellingShingle |
chronology Wisconsinan Laurentide Ice Sheet luminescence postglacial Earth Sciences Geology Physical Sciences and Mathematics Munyikwa, K. Feathers, J. Rittenour, Tammy M. Shrimpton, H. Constraining the chronology of the Late Wisconsinan retreat of the Laurentide Ice Sheet from western Canada using luminescence ages from postglacial aeolian dune sequences |
topic_facet |
chronology Wisconsinan Laurentide Ice Sheet luminescence postglacial Earth Sciences Geology Physical Sciences and Mathematics |
description |
Optically stimulated luminescence (OSL) dating of quartz extracts from postglacial aeolian dunes from central Alberta in western Canada points to a landscape that was free of ice as early as 15 ka. Data from profiles where multiple ages have been obtained indicate an increase in depositional age with depth, suggesting that older aeolian sands underlie the dated sequences. The OSL ages present plausible minimum age constraints for the retreat of the Laurentide Ice Sheet (LIS) towards the end of the Late Wisconsinan glaciation. Previous reconstructions of the LIS recession have relied on radiocarbon chronologies, despite the scarcity of contemporaneous radiocarbon-bearing material for large parts of western Canada. While the OSL chronology may be deemed concordant with ice sheet margin retreat models determined using radiocarbon data, there appears to be a systematic lag in the radiocarbon ages which may reflect that aeolian activity is initiated prior to the proliferation of organic material. The OSL chronology reported in this study does not preclude the emergence of a wide deglacial corridor between the LIS and the Cordilleran Ice Sheet by 15 ka or earlier. The possibility of such a passage would resuscitate the notion of an ice-free corridor that appeared early enough to afford the first peoples of the Americas a navigable inland migratory passage from Beringia to south of the North American ice sheets. More broadly, the corridor would also have allowed genetic exchanges between the Beringian refugium and the American middle and low latitudes. |
format |
Text |
author |
Munyikwa, K. Feathers, J. Rittenour, Tammy M. Shrimpton, H. |
author_facet |
Munyikwa, K. Feathers, J. Rittenour, Tammy M. Shrimpton, H. |
author_sort |
Munyikwa, K. |
title |
Constraining the chronology of the Late Wisconsinan retreat of the Laurentide Ice Sheet from western Canada using luminescence ages from postglacial aeolian dune sequences |
title_short |
Constraining the chronology of the Late Wisconsinan retreat of the Laurentide Ice Sheet from western Canada using luminescence ages from postglacial aeolian dune sequences |
title_full |
Constraining the chronology of the Late Wisconsinan retreat of the Laurentide Ice Sheet from western Canada using luminescence ages from postglacial aeolian dune sequences |
title_fullStr |
Constraining the chronology of the Late Wisconsinan retreat of the Laurentide Ice Sheet from western Canada using luminescence ages from postglacial aeolian dune sequences |
title_full_unstemmed |
Constraining the chronology of the Late Wisconsinan retreat of the Laurentide Ice Sheet from western Canada using luminescence ages from postglacial aeolian dune sequences |
title_sort |
constraining the chronology of the late wisconsinan retreat of the laurentide ice sheet from western canada using luminescence ages from postglacial aeolian dune sequences |
publisher |
Hosted by Utah State University Libraries |
publishDate |
2011 |
url |
https://digitalcommons.usu.edu/geology_facpub/265 |
long_lat |
ENVELOPE(78.139,78.139,-68.582,-68.582) |
geographic |
Canada The Corridor |
geographic_facet |
Canada The Corridor |
genre |
Ice Sheet Beringia |
genre_facet |
Ice Sheet Beringia |
op_source |
Geosciences Faculty Publications |
op_relation |
https://digitalcommons.usu.edu/geology_facpub/265 |
op_rights |
Copyright for this work is held by the author. Transmission or reproduction of materials protected by copyright beyond that allowed by fair use requires the written permission of the copyright owners. Works not in the public domain cannot be commercially exploited without permission of the copyright owner. Responsibility for any use rests exclusively with the user. For more information contact the Institutional Repository Librarian at digitalcommons@usu.edu. |
op_rightsnorm |
PDM |
_version_ |
1766030484380319744 |