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Degree of Weathering of H-Chondrites from Frontier Mountain, AntarcticaOne of the factors that determines the survival time of meteorites on the Earth's surface is the rate of weathering. For meteorites from hot deserts, a clear correlation is found between the degree of weathering and the terrestrial age, but for Antarctic meteorites this correlation is weak or even lacking. The lack of a clear correlation can partly be attributed to the two-stage history of many Antarctic meteorites, which spend part of their terrestrial residence time in the ice before they are exposed on the ice. Recently, it was found that for Lewis Cliff (LEW) meteorites local conditions on the ice play an important role in the weathering process. This work focuses on weathering effects in ordinary chondrites from Frontier Mountain (FRO), North Victoria Land. Although most FRO meteorites were classified as weathering category A or B, many are contaminated with terrestrial uranium, deposited from meltwater. This suggests that weathering plays a more significant role than the qualitative A-B-C weathering index indicates. We therefore determined the degree of weathering more quantitatively, by deriving the amount of oxidized metal from the concentrations of Fe and Ni in the nonmagnetic fraction of 23 H-chondrites and 1 L-chondrite. The results will be compared with those of LEW meteorites and will be discussed in terms of terrestrial age and location of find on the ice.
Document ID
20000034793
Document Type
Conference Paper
Authors
Welten, K. C. (California Univ. Berkeley, CA United States)
Nishiizumi, Kunihiko (California Univ. Berkeley, CA United States)
Date Acquired
August 19, 2013
Publication Date
January 1, 1999
Publication Information
Publication: Workshop on Extraterrestrial Materials from Cold and Hot Deserts
Subject Category
Astrophysics
Funding Number(s)
CONTRACT_GRANT: NAG5-4992
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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IDRelationTitle20000034770Analytic PrimaryWorkshop on Extraterrestrial Materials from Cold and Hot Deserts
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