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Title: Thermal legacy of a large paleolake in Taylor Valley, East Antarctica, as evidenced by an airborne electromagnetic survey
Abstract. Previous studies of the lakes of the McMurdo Dry Valleys haveattempted to constrain lake level history, and results suggest the lakeshave undergone hundreds of meters of lake level change within the last20 000 years. Past studies have utilized the interpretation of geologicdeposits, lake chemistry, and ice sheet history to deduce lake levelhistory; however a substantial amount of disagreement remains between thefindings, indicating a need for further investigation using new techniques.This study utilizes a regional airborne resistivity survey to provide novelinsight into the paleohydrology of the region. Mean resistivity mapsrevealed an extensive brine beneath the Lake Fryxell basin, which isinterpreted as a legacy groundwater signal from higher lake levels in thepast. Resistivity data suggest that active permafrost formation has beenongoing since the onset of lake drainage and that as recently as 1500–4000 years BP, lake levels were over 60 m higher than present. This coincideswith a warmer-than-modern paleoclimate throughout the Holocene inferred bythe nearby Taylor Dome ice core record. Our results indicate Mid to LateHolocene lake level high stands, which runs counter to previous researchfinding a colder and drier era with little hydrologic activity throughoutthe last 5000 years.  more » « less
Award ID(s):
1644187 1637708 1643536
NSF-PAR ID:
10293042
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
The Cryosphere
Volume:
15
Issue:
8
ISSN:
1994-0424
Page Range / eLocation ID:
3577 to 3593
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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