Luminescence Dating of Paleolake Deltas and Glacial Deposits in Garwood Valley, Antarctica: Implications for Climate, Ross Ice Sheet Dynamics, and Paleolake Duration
The formation of perched deltas and other lacustrine deposits in the McMurdo Dry Valleys of Antarctica is widely considered to be evidence of valley-filling lakes dammed by the grounded Ross Sea ice sheet during the local Last Glacial Maximum, with lake drainage interpreted as a record of grounding...
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ftutahsudc:oai:digitalcommons.usu.edu:geology_facpub-1526 2023-05-15T13:44:31+02:00 Luminescence Dating of Paleolake Deltas and Glacial Deposits in Garwood Valley, Antarctica: Implications for Climate, Ross Ice Sheet Dynamics, and Paleolake Duration Levy, Joseph S. Rittenour, Tammy M. Fountain, Andrew G. O'Connor, Jim E. Geological Society of America 2017-09-01T07:00:00Z https://digitalcommons.usu.edu/geology_facpub/527 unknown Hosted by Utah State University Libraries https://digitalcommons.usu.edu/geology_facpub/527 Geosciences Faculty Publications McMurdo Dry Valleys Antartica Last Glacial Maximum Paleolake deltas Earth Sciences Geology Physical Sciences and Mathematics text 2017 ftutahsudc 2022-03-07T21:51:45Z The formation of perched deltas and other lacustrine deposits in the McMurdo Dry Valleys of Antarctica is widely considered to be evidence of valley-filling lakes dammed by the grounded Ross Sea ice sheet during the local Last Glacial Maximum, with lake drainage interpreted as a record of grounding line retreat. We used luminescence dating to determine the age of paleolake deltas and glacial tills in Garwood Valley, a coastal dry valley that opens to the Ross Sea. Luminescence ages are stratigraphically consistent with radiocarbon results from algal mats within the same delta deposits but suggest radiocarbon dates from lacustrine carbonates may overestimate deposit ages by thousands of years. Results suggest that late Holocene delta deposition into paleolake Howard in Garwood Valley persisted until ca. 3.5 ka. This is significantly younger than the date when grounded ice is thought to have retreated from the Ross Sea. Our evidence suggests that the local, stranded ice-cored till topography in Garwood Valley, rather than regional ice-sheet dynamics, may have controlled lake levels for some McMurdo Dry Valleys paleolakes. Age control from the supraglacial Ross Sea drift suggests grounding and up-valley advance of the Ross Sea ice sheet into Garwood valley during marine oxygen isotope stage (MIS) 4 (71–78 ka) and the local Last Glacial Maximum (9–10 ka). This work demonstrates the power of combining luminescence dating with existing radiocarbon data sets to improve understanding of the relationships among paleolake formation, glacial position, and stream discharge in response to climate change. Text Antarc* Antarctica antartic* Ice Sheet McMurdo Dry Valleys Ross Sea Sea ice Utah State University: DigitalCommons@USU Garwood ENVELOPE(164.283,164.283,-78.033,-78.033) Garwood Valley ENVELOPE(164.167,164.167,-78.033,-78.033) McMurdo Dry Valleys Ross Sea |
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Utah State University: DigitalCommons@USU |
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ftutahsudc |
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unknown |
topic |
McMurdo Dry Valleys Antartica Last Glacial Maximum Paleolake deltas Earth Sciences Geology Physical Sciences and Mathematics |
spellingShingle |
McMurdo Dry Valleys Antartica Last Glacial Maximum Paleolake deltas Earth Sciences Geology Physical Sciences and Mathematics Levy, Joseph S. Rittenour, Tammy M. Fountain, Andrew G. O'Connor, Jim E. Luminescence Dating of Paleolake Deltas and Glacial Deposits in Garwood Valley, Antarctica: Implications for Climate, Ross Ice Sheet Dynamics, and Paleolake Duration |
topic_facet |
McMurdo Dry Valleys Antartica Last Glacial Maximum Paleolake deltas Earth Sciences Geology Physical Sciences and Mathematics |
description |
The formation of perched deltas and other lacustrine deposits in the McMurdo Dry Valleys of Antarctica is widely considered to be evidence of valley-filling lakes dammed by the grounded Ross Sea ice sheet during the local Last Glacial Maximum, with lake drainage interpreted as a record of grounding line retreat. We used luminescence dating to determine the age of paleolake deltas and glacial tills in Garwood Valley, a coastal dry valley that opens to the Ross Sea. Luminescence ages are stratigraphically consistent with radiocarbon results from algal mats within the same delta deposits but suggest radiocarbon dates from lacustrine carbonates may overestimate deposit ages by thousands of years. Results suggest that late Holocene delta deposition into paleolake Howard in Garwood Valley persisted until ca. 3.5 ka. This is significantly younger than the date when grounded ice is thought to have retreated from the Ross Sea. Our evidence suggests that the local, stranded ice-cored till topography in Garwood Valley, rather than regional ice-sheet dynamics, may have controlled lake levels for some McMurdo Dry Valleys paleolakes. Age control from the supraglacial Ross Sea drift suggests grounding and up-valley advance of the Ross Sea ice sheet into Garwood valley during marine oxygen isotope stage (MIS) 4 (71–78 ka) and the local Last Glacial Maximum (9–10 ka). This work demonstrates the power of combining luminescence dating with existing radiocarbon data sets to improve understanding of the relationships among paleolake formation, glacial position, and stream discharge in response to climate change. |
author2 |
Geological Society of America |
format |
Text |
author |
Levy, Joseph S. Rittenour, Tammy M. Fountain, Andrew G. O'Connor, Jim E. |
author_facet |
Levy, Joseph S. Rittenour, Tammy M. Fountain, Andrew G. O'Connor, Jim E. |
author_sort |
Levy, Joseph S. |
title |
Luminescence Dating of Paleolake Deltas and Glacial Deposits in Garwood Valley, Antarctica: Implications for Climate, Ross Ice Sheet Dynamics, and Paleolake Duration |
title_short |
Luminescence Dating of Paleolake Deltas and Glacial Deposits in Garwood Valley, Antarctica: Implications for Climate, Ross Ice Sheet Dynamics, and Paleolake Duration |
title_full |
Luminescence Dating of Paleolake Deltas and Glacial Deposits in Garwood Valley, Antarctica: Implications for Climate, Ross Ice Sheet Dynamics, and Paleolake Duration |
title_fullStr |
Luminescence Dating of Paleolake Deltas and Glacial Deposits in Garwood Valley, Antarctica: Implications for Climate, Ross Ice Sheet Dynamics, and Paleolake Duration |
title_full_unstemmed |
Luminescence Dating of Paleolake Deltas and Glacial Deposits in Garwood Valley, Antarctica: Implications for Climate, Ross Ice Sheet Dynamics, and Paleolake Duration |
title_sort |
luminescence dating of paleolake deltas and glacial deposits in garwood valley, antarctica: implications for climate, ross ice sheet dynamics, and paleolake duration |
publisher |
Hosted by Utah State University Libraries |
publishDate |
2017 |
url |
https://digitalcommons.usu.edu/geology_facpub/527 |
long_lat |
ENVELOPE(164.283,164.283,-78.033,-78.033) ENVELOPE(164.167,164.167,-78.033,-78.033) |
geographic |
Garwood Garwood Valley McMurdo Dry Valleys Ross Sea |
geographic_facet |
Garwood Garwood Valley McMurdo Dry Valleys Ross Sea |
genre |
Antarc* Antarctica antartic* Ice Sheet McMurdo Dry Valleys Ross Sea Sea ice |
genre_facet |
Antarc* Antarctica antartic* Ice Sheet McMurdo Dry Valleys Ross Sea Sea ice |
op_source |
Geosciences Faculty Publications |
op_relation |
https://digitalcommons.usu.edu/geology_facpub/527 |
_version_ |
1766202802957189120 |