A newly discovered subglacial lake in East Antarctica likely hosts a valuable sedimentary record of ice and climate change

The Princess Elizabeth Land sector of the East Antarctic Ice Sheet is a significant reservoir of grounded ice and is adjacent to regions that experienced great change during Quaternary glacial cycles and Pliocene warm episodes. The existence of an extensive subglacial water system in Princess Elizab...

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Bibliographic Details
Published in:Geology
Main Authors: Yan, S, Blankenship, D, Greenbaum, J, Young, D, Li, L, Rutishauser, A, Guo, J, Roberts, J, Van Ommen, T, Siegert, M, Sun, B
Other Authors: British Council (UK), Natural Environment Research Council (NERC)
Format: Article in Journal/Newspaper
Language:unknown
Published: Geological Society of America 2022
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Online Access:http://hdl.handle.net/10044/1/96662
https://doi.org/10.1130/G50009.1
Description
Summary:The Princess Elizabeth Land sector of the East Antarctic Ice Sheet is a significant reservoir of grounded ice and is adjacent to regions that experienced great change during Quaternary glacial cycles and Pliocene warm episodes. The existence of an extensive subglacial water system in Princess Elizabeth Land (to date only inferred from satellite imagery) bears the potential to significantly impact the thermal and kinematic conditions of the overlying ice sheet. We confirm the existence of a major subglacial lake, herein referred to as Lake Snow Eagle (LSE), for the first time using recently acquired aerogeophysical data. We systematically investigated LSE’s geological characteristics and bathymetry from two-dimensional geophysical inversion models. The inversion results suggest that LSE is located along a compressional geologic boundary, which provides reference for future characterization of the geologic and tectonic context of this region. We estimate LSE to be ~42 km in length and 370 km2 in area, making it one of the largest subglacial lakes in Antarctica. Additionally, the airborne ice-penetrating radar observations and geophysical inversions reveal a layer of unconsolidated water-saturated sediment around and at the bottom of LSE, which—given the ultralow rates of sedimentation expected in such environments—may archive valuable records of paleoenvironmental changes and the early history of East Antarctic Ice Sheet evolution in Princess Elizabeth Land.