Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina
At several times during the Quaternary, a major eastward-flowing outlet glacier of the former Patagonian Ice Sheet occupied the Lago San Martin Valley in Argentina (49°S, 72°W). We present a glacial chronology for the valley based on geomorphological mapping and cosmogenic nuclide (10Be) exposure ag...
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ftuglasgow:oai:eprints.gla.ac.uk:74928 2023-05-15T16:40:58+02:00 Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina Glasser, N.F. Jansson, K.N. Goodfellow, B.W. de Angelis, H. Rodnight, H. Rood, D.H. 2011-05 http://eprints.gla.ac.uk/74928/ unknown Glasser, N.F., Jansson, K.N., Goodfellow, B.W., de Angelis, H., Rodnight, H. and Rood, D.H. <http://eprints.gla.ac.uk/view/author/28408.html> (2011) Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina. Quaternary Research <http://eprints.gla.ac.uk/view/journal_volume/Quaternary_Research.html>, 75(3), pp. 636-646. (doi:10.1016/j.yqres.2010.11.005 <http://dx.doi.org/10.1016/j.yqres.2010.11.005>) Articles PeerReviewed 2011 ftuglasgow https://doi.org/10.1016/j.yqres.2010.11.005 2021-09-23T22:52:22Z At several times during the Quaternary, a major eastward-flowing outlet glacier of the former Patagonian Ice Sheet occupied the Lago San Martin Valley in Argentina (49°S, 72°W). We present a glacial chronology for the valley based on geomorphological mapping and cosmogenic nuclide (10Be) exposure ages (n = 10) of boulders on moraines and lake shorelines. There are five prominent moraine belts in the Lago San Martin Valley, associated with extensive sandar (glaciofluvial outwash plains) and former lake shorelines. Cosmogenic nuclide exposure ages for boulders on these moraines indicate that they formed at 14.3 ± 1.7 ka, 22.4 ± 2.3 ka, 34.4 ± 3.4 ka to 37.6 ± 3.4 ka (and possibly 60 ± 3.5 ka), and 99 ± 11 ka (1σ). These dated glacier advances differ from published chronologies from the Lago San Martin Valley based on 14C age determinations from organic sediments and molluscs in meltwater channels directly in front of moraines or in kettleholes within end moraine ridges. The moraine boulder ages also point to possible pre-LGM glacial advances during the last glacial cycle and a key observation from our data is that the LGM glaciers were probably less extensive in the Lago San Martin Valley than previously thought. Article in Journal/Newspaper Ice Sheet University of Glasgow: Enlighten - Publications Argentina Martin Valley ENVELOPE(-36.350,-36.350,-54.283,-54.283) Sandar ENVELOPE(-18.255,-18.255,63.521,63.521) Quaternary Research 75 3 636 646 |
institution |
Open Polar |
collection |
University of Glasgow: Enlighten - Publications |
op_collection_id |
ftuglasgow |
language |
unknown |
description |
At several times during the Quaternary, a major eastward-flowing outlet glacier of the former Patagonian Ice Sheet occupied the Lago San Martin Valley in Argentina (49°S, 72°W). We present a glacial chronology for the valley based on geomorphological mapping and cosmogenic nuclide (10Be) exposure ages (n = 10) of boulders on moraines and lake shorelines. There are five prominent moraine belts in the Lago San Martin Valley, associated with extensive sandar (glaciofluvial outwash plains) and former lake shorelines. Cosmogenic nuclide exposure ages for boulders on these moraines indicate that they formed at 14.3 ± 1.7 ka, 22.4 ± 2.3 ka, 34.4 ± 3.4 ka to 37.6 ± 3.4 ka (and possibly 60 ± 3.5 ka), and 99 ± 11 ka (1σ). These dated glacier advances differ from published chronologies from the Lago San Martin Valley based on 14C age determinations from organic sediments and molluscs in meltwater channels directly in front of moraines or in kettleholes within end moraine ridges. The moraine boulder ages also point to possible pre-LGM glacial advances during the last glacial cycle and a key observation from our data is that the LGM glaciers were probably less extensive in the Lago San Martin Valley than previously thought. |
format |
Article in Journal/Newspaper |
author |
Glasser, N.F. Jansson, K.N. Goodfellow, B.W. de Angelis, H. Rodnight, H. Rood, D.H. |
spellingShingle |
Glasser, N.F. Jansson, K.N. Goodfellow, B.W. de Angelis, H. Rodnight, H. Rood, D.H. Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina |
author_facet |
Glasser, N.F. Jansson, K.N. Goodfellow, B.W. de Angelis, H. Rodnight, H. Rood, D.H. |
author_sort |
Glasser, N.F. |
title |
Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina |
title_short |
Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina |
title_full |
Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina |
title_fullStr |
Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina |
title_full_unstemmed |
Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina |
title_sort |
cosmogenic nuclide exposure ages for moraines in the lago san martin valley, argentina |
publishDate |
2011 |
url |
http://eprints.gla.ac.uk/74928/ |
long_lat |
ENVELOPE(-36.350,-36.350,-54.283,-54.283) ENVELOPE(-18.255,-18.255,63.521,63.521) |
geographic |
Argentina Martin Valley Sandar |
geographic_facet |
Argentina Martin Valley Sandar |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_relation |
Glasser, N.F., Jansson, K.N., Goodfellow, B.W., de Angelis, H., Rodnight, H. and Rood, D.H. <http://eprints.gla.ac.uk/view/author/28408.html> (2011) Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina. Quaternary Research <http://eprints.gla.ac.uk/view/journal_volume/Quaternary_Research.html>, 75(3), pp. 636-646. (doi:10.1016/j.yqres.2010.11.005 <http://dx.doi.org/10.1016/j.yqres.2010.11.005>) |
op_doi |
https://doi.org/10.1016/j.yqres.2010.11.005 |
container_title |
Quaternary Research |
container_volume |
75 |
container_issue |
3 |
container_start_page |
636 |
op_container_end_page |
646 |
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1766031410306482176 |