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Lookup NU author(s): Dr Stuart Dunning
This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).
Erosion rates offer insight on landscape development and the relative importance of chemical and physical processes of weathering. Minimal chemical weathering makes Antarctica an ideal location in which to compare the physical weathering of carbonate rocksto other lithologies. Here we report the first cosmogenic nuclide-derived erosion rates for carbonate rocks in Antarctica. Carbonate samples collected in the southernmost Ellsworth Mountains reflect a 36Cl erosion rate of 0.22 ± 0.02 mm/ka. This erosion rate is consistent with other reported Antarctic erosion rates, but is lower than 36Cl erosion rates derived from other arid regions in the world. These results are integrated with a continent-wide reanalysis of 28 cosmogenic nuclide erosion rate studies (>200 measurements), which comprise numerous rock types and multiple cosmogenic nuclides. By combining cosmogenic nuclide-derived erosion rates across studies, the larger trends provide insight into factors (e.g. lithology, glacial history, and availability of abrasive material) affecting subaerial erosion rates in Antarctica. Statistical analysis of the compiled data set shows differences based on lithology, with sandstone having the largest range of erosion rates. The compiled data also reveals higher erosion rates in areas with a large potential sediment supply, like the Dry Valleys. Samples collected from boulders yield lower erosion rates than those collected from bedrock, likely due to a combination of physical processes that affect boulders and bedrock differently, and glacial history, which can affect the apparent cosmogenic-nuclide derived erosion rate.
Author(s): Marrero SM, Hein AS, Naylor M, Attal M, Shanks R, Winter K, Woodward J, Dunning S, Westoby M, Sugden D
Publication type: Article
Publication status: Published
Journal: Earth and Planetary Science Letters
Print publication date: 01/11/2018
Online publication date: 30/08/2018
Acceptance date: 08/08/2018
Date deposited: 31/08/2018
ISSN (electronic): 0012-821X
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