Mineralogical examination of the Yamato-79 achondrites : Polymict eucrites and ureilites

P(論文) Mineralogical examination of the first one-third of the Yamato-79 achondrites collected by the JARE party in 1979 and 1980 seasons revealed that eight of them are polymict eucrites similar to the Antarctic polymict eucrites reported previously, and that Y-790727 is a howardite and Y-790981 is...

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Bibliographic Details
Main Authors: Takeda, Hiroshi, Yanai, Keizo
Language:English
Published: 1982
Subjects:
Online Access:https://nipr.repo.nii.ac.jp/record/1382/files/KJ00000012016.pdf
https://nipr.repo.nii.ac.jp/records/1382
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Summary:P(論文) Mineralogical examination of the first one-third of the Yamato-79 achondrites collected by the JARE party in 1979 and 1980 seasons revealed that eight of them are polymict eucrites similar to the Antarctic polymict eucrites reported previously, and that Y-790727 is a howardite and Y-790981 is a ureilite. The following Yamato-79 eucrites show features different from the known types. Y-790122 and Y-790266 are rich in lithic clasts. A thin section of Y-790122 consists of four different clast types joined together face to face with little matrix between them. Almost one-third of Y-790266 is a medium-grained subophitic basalt with pyroxene chemical zoning trends which simulate the host pigeonite and exsolved augite pair of the ordinary eucrites such as Juvinas. Y-790007 contains abundant cumulate eucrite clasts identical to Binda in their pyroxene exsolution texture and chemistry. departmental bulletin paper