Summary: | P(論文) The Yamato-74442 chondrite (LL) consists of high-k lithic fragments, non-recrystallized lithic fragments, recrystallized lithic fragments, chondrules, mineral fragments and matrix. The microporphyritic texture and the chemical compositions of groundmass of the high-K lithic fragments suggest that they were formed by the melting of a rock consisting mainly of olivine, pyroxenes and K-feldspar, and experienced rapid cooling. Non-recrystallized lithic fragments and chondrules have the same chemical composition as the most ferrous chondrules in the Yamato-74191 chondrite (L3). Recrystallized lithic fragments were produced by the heating up to 1000℃ of the same materials as the non-recrystallized lithic fragments. Mineral fragments and matrix were formed by disaggregation of the other units. departmental bulletin paper
|