Groundwater and Thermal Legacy of a Large Paleolake in Taylor Valley, East Antarctica as Evidenced by Airborne Electromagnetic and Sedimentological Techniques
During the Last Glacial Maximum, grounded ice in the Ross Sea extended into the otherwise ice-free McMurdo Dry Valleys, creating a series of large ice dammed paleolakes. Grounded ice within the mouth of Taylor Valley allowed for lake levels to reach elevations not possible at modern day and formed w...
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ftlouisianastuir:oai:digitalcommons.lsu.edu:gradschool_theses-5779 2023-06-11T04:06:07+02:00 Groundwater and Thermal Legacy of a Large Paleolake in Taylor Valley, East Antarctica as Evidenced by Airborne Electromagnetic and Sedimentological Techniques Myers, Krista Falcon 2018-07-02T07:00:00Z application/pdf https://digitalcommons.lsu.edu/gradschool_theses/4776 https://doi.org/10.31390/gradschool_theses.4776 https://digitalcommons.lsu.edu/context/gradschool_theses/article/5779/viewcontent/myers_thesis.pdf unknown LSU Digital Commons https://digitalcommons.lsu.edu/gradschool_theses/4776 doi:10.31390/gradschool_theses.4776 https://digitalcommons.lsu.edu/context/gradschool_theses/article/5779/viewcontent/myers_thesis.pdf LSU Master's Theses Antarctica McMurdo Dry Valleys hydrology limnology text 2018 ftlouisianastuir https://doi.org/10.31390/gradschool_theses.4776 2023-05-28T19:17:28Z During the Last Glacial Maximum, grounded ice in the Ross Sea extended into the otherwise ice-free McMurdo Dry Valleys, creating a series of large ice dammed paleolakes. Grounded ice within the mouth of Taylor Valley allowed for lake levels to reach elevations not possible at modern day and formed what is known as Glacial Lake Washburn (GLW). GLW extended from the eastern portion of Taylor Valley roughly 20 km west to a level ~300 m higher than modern day Lake Fryxell. The formation and existence of GLW has been debated, though previous studies correlate the timing of GLW with early Holocene grounded ice. Evidence of GLW has largely been constrained to the interpretation of glacial deposits and fluvial features such as lacustrine deposits, strandlines, and preserved paleodeltas. GIS and remote sensing techniques paired with regional resistivity data provide new insight into the paleohydrology of the region. To quantify the extent of GLW, paleodelta locations were mapped using high resolution LiDAR digital elevation models and satellite imagery. Delta topset elevations were correlated between three streams in Fryxell basin to determine paleolake levels. Additionally, mean resistivity maps generated from airborne electromagnetic survey data (SkyTEM) reveal an extensive groundwater system within Fryxell basin which is interpreted as a legacy groundwater signal from GLW. Resistivity data suggests that active permafrost formation has been ongoing since onset of lake drainage, and that lake levels were over 60 m higher than modern only 1,000 – 2,000 yr BP. This coincides with a warmer than modern paleoclimate inferred by ice core records, indicating a dynamic hydrological system that is highly sensitive to small changes in climate. As global temperatures increase, Lake Fryxell will continue to experience highly variable lake levels. Lakes and groundwater within the McMurdo Dry Valleys are critical to understanding impacts on the broader ecosystem which is largely driven by the availability of liquid water. Text Antarc* Antarctica East Antarctica Ice ice core McMurdo Dry Valleys permafrost Ross Sea LSU Digital Commons (Louisiana State University) East Antarctica Fryxell ENVELOPE(163.183,163.183,-77.617,-77.617) Glacial Lake ENVELOPE(-129.463,-129.463,58.259,58.259) Lake Fryxell ENVELOPE(163.183,163.183,-77.617,-77.617) McMurdo Dry Valleys Ross Sea Taylor Valley ENVELOPE(163.000,163.000,-77.617,-77.617) Washburn ENVELOPE(-86.133,-86.133,-77.617,-77.617) |
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Open Polar |
collection |
LSU Digital Commons (Louisiana State University) |
op_collection_id |
ftlouisianastuir |
language |
unknown |
topic |
Antarctica McMurdo Dry Valleys hydrology limnology |
spellingShingle |
Antarctica McMurdo Dry Valleys hydrology limnology Myers, Krista Falcon Groundwater and Thermal Legacy of a Large Paleolake in Taylor Valley, East Antarctica as Evidenced by Airborne Electromagnetic and Sedimentological Techniques |
topic_facet |
Antarctica McMurdo Dry Valleys hydrology limnology |
description |
During the Last Glacial Maximum, grounded ice in the Ross Sea extended into the otherwise ice-free McMurdo Dry Valleys, creating a series of large ice dammed paleolakes. Grounded ice within the mouth of Taylor Valley allowed for lake levels to reach elevations not possible at modern day and formed what is known as Glacial Lake Washburn (GLW). GLW extended from the eastern portion of Taylor Valley roughly 20 km west to a level ~300 m higher than modern day Lake Fryxell. The formation and existence of GLW has been debated, though previous studies correlate the timing of GLW with early Holocene grounded ice. Evidence of GLW has largely been constrained to the interpretation of glacial deposits and fluvial features such as lacustrine deposits, strandlines, and preserved paleodeltas. GIS and remote sensing techniques paired with regional resistivity data provide new insight into the paleohydrology of the region. To quantify the extent of GLW, paleodelta locations were mapped using high resolution LiDAR digital elevation models and satellite imagery. Delta topset elevations were correlated between three streams in Fryxell basin to determine paleolake levels. Additionally, mean resistivity maps generated from airborne electromagnetic survey data (SkyTEM) reveal an extensive groundwater system within Fryxell basin which is interpreted as a legacy groundwater signal from GLW. Resistivity data suggests that active permafrost formation has been ongoing since onset of lake drainage, and that lake levels were over 60 m higher than modern only 1,000 – 2,000 yr BP. This coincides with a warmer than modern paleoclimate inferred by ice core records, indicating a dynamic hydrological system that is highly sensitive to small changes in climate. As global temperatures increase, Lake Fryxell will continue to experience highly variable lake levels. Lakes and groundwater within the McMurdo Dry Valleys are critical to understanding impacts on the broader ecosystem which is largely driven by the availability of liquid water. |
format |
Text |
author |
Myers, Krista Falcon |
author_facet |
Myers, Krista Falcon |
author_sort |
Myers, Krista Falcon |
title |
Groundwater and Thermal Legacy of a Large Paleolake in Taylor Valley, East Antarctica as Evidenced by Airborne Electromagnetic and Sedimentological Techniques |
title_short |
Groundwater and Thermal Legacy of a Large Paleolake in Taylor Valley, East Antarctica as Evidenced by Airborne Electromagnetic and Sedimentological Techniques |
title_full |
Groundwater and Thermal Legacy of a Large Paleolake in Taylor Valley, East Antarctica as Evidenced by Airborne Electromagnetic and Sedimentological Techniques |
title_fullStr |
Groundwater and Thermal Legacy of a Large Paleolake in Taylor Valley, East Antarctica as Evidenced by Airborne Electromagnetic and Sedimentological Techniques |
title_full_unstemmed |
Groundwater and Thermal Legacy of a Large Paleolake in Taylor Valley, East Antarctica as Evidenced by Airborne Electromagnetic and Sedimentological Techniques |
title_sort |
groundwater and thermal legacy of a large paleolake in taylor valley, east antarctica as evidenced by airborne electromagnetic and sedimentological techniques |
publisher |
LSU Digital Commons |
publishDate |
2018 |
url |
https://digitalcommons.lsu.edu/gradschool_theses/4776 https://doi.org/10.31390/gradschool_theses.4776 https://digitalcommons.lsu.edu/context/gradschool_theses/article/5779/viewcontent/myers_thesis.pdf |
long_lat |
ENVELOPE(163.183,163.183,-77.617,-77.617) ENVELOPE(-129.463,-129.463,58.259,58.259) ENVELOPE(163.183,163.183,-77.617,-77.617) ENVELOPE(163.000,163.000,-77.617,-77.617) ENVELOPE(-86.133,-86.133,-77.617,-77.617) |
geographic |
East Antarctica Fryxell Glacial Lake Lake Fryxell McMurdo Dry Valleys Ross Sea Taylor Valley Washburn |
geographic_facet |
East Antarctica Fryxell Glacial Lake Lake Fryxell McMurdo Dry Valleys Ross Sea Taylor Valley Washburn |
genre |
Antarc* Antarctica East Antarctica Ice ice core McMurdo Dry Valleys permafrost Ross Sea |
genre_facet |
Antarc* Antarctica East Antarctica Ice ice core McMurdo Dry Valleys permafrost Ross Sea |
op_source |
LSU Master's Theses |
op_relation |
https://digitalcommons.lsu.edu/gradschool_theses/4776 doi:10.31390/gradschool_theses.4776 https://digitalcommons.lsu.edu/context/gradschool_theses/article/5779/viewcontent/myers_thesis.pdf |
op_doi |
https://doi.org/10.31390/gradschool_theses.4776 |
_version_ |
1768377889603977216 |