A New Carbonaceous Chondrite Grouplet, CA

Kimura M., Yamaguchi A., Greenwood R. C., Imae N., Komtsu M.

82nd Annual Meeting of The Meteoritical Society 2019

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“While the majority of carbonaceous (C) chondrites can be assigned to one of eight major groups, some meteorites are less easy to categorize and hence are designated as “ungrouped” [1]. Yamato (Y)-82094 is one such example, having a number of characteristics which distinguish it from other C chondrites: 1) chondrules are highly abundant, 2) chondrule size is intermediate between CV and CO, and 3) the matrix abundance is low, being similar to that of ordinary (O) chondrites. However, the abundance of refractory inclusions, and oxygen isotopic and chemical compositions are typical of C chondrites. Therefore, Y-82094 is an ungrouped C chondrite [2]. Recently, two further unusual carbonaceous chondrites, Asuka 09003 and A 09535 have been reported [3, 4]. Here we present our results for these new chondrites, compare them to Y-82094 and discuss their classification. “