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Regolith transport in the Dry Valleys of Antarctica

J. Putkonen·M. Rosales·N. Turpen·D. Morgan·G. Balco·M. Donaldson
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Abstract

The stability of ground surface and preservation of landforms that record past events and environments is of great importance as the geologic and climatic history is evaluated in the Dry Valleys of Antarctica. Currently little is known about the regolith transport that tends to eradicate and confound this record and regolith transport is itself an environmental indicator. Based on analyses of repeat photographs, soil traps, and pebble transport distances, it was found that there is a large spatial variation in topographic diffusivities at least in the annual basis and that counter intuitively the highest topographic diffusivities are found in the alpine valleys that are located farther inland from the coast where the lowest topographic diffusivities were recorded. An average topographic diffusivity for the Dry Valleys was determined to be 10M -5 –10 -4 m 2 /yr. This average topographic diffusivity is surprisingly large, equaling or bordering the smallest values from elsewhere on Earth

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J. Putkonen, M. Rosales, N. Turpen, D. Morgan, G. Balco, M. Donaldson. 2007. Regolith transport in the Dry Valleys of Antarctica. https://doi.org/10.3133/ofr20071047srp103

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