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Thermomagnetic analysis of meteorites, 2. C2 chondrites

D.E. Watson·E.E. Larson·J.M. Herndon·M.W. Rowe
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Abstract

Samples of all eighteen of the known C2 chondrites have been analyzed thermomagnetically. For eleven of these, initial Fe 3 O 4 content is low (generally <1%) and the J s -T curves are irreversible. The heating curves show variable greater (up to 10 times) than it is initially. This behavior is attributed to the production of magnetite from a thermally unstable phase — apparently FeS. Four of the remaining seven C2 chondrites contain Fe 3 O 4 as the only significant magnetic phase: initial magnetite contents range from 4 to 13%. The remaining three C2 chondrites contain iron or nickel-iron in addition to Fe 3 O 4 . These seven C2 chondrites show little evidence of the breakdown of a thermally unstable phase.

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D.E. Watson, E.E. Larson, J.M. Herndon, M.W. Rowe. 1975. Thermomagnetic analysis of meteorites, 2. C2 chondrites. https://doi.org/10.1016/0012-821x(75)90167-3

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