Host: Abstracts of Annual Meeting of the Geochemical Society of Japan
Name : Abstracts of Annual Meeting of the Geochemical Society of Japan
Number : 71
Date : September 18, 2024 - September 20, 2024
Pages 145-
Chondrules and isolated grains of olivine, pyroxene, spinel, and corundum were found in the Yamato(Y)-980115 CI chondrite. A peak of size distribution of chondrules and anhydrous minerals occurs at 1-3 um, which is smaller than those of chondrules and anhydrous minerals in other chondrites. Most of the olivine grains have FeO-rich compositions, which is distinct from olivine in other carbonaceous chondrites. Most of the chondrules are type II with porphyritic textures, and the olivine phenocrysts show Fe-Mg zoning. While parent bodies of CI chondrites and asteroid Ryugu are considered to have accreted in the outer regions of the protoplanetary disk, chondrules, CAIs, and anhydrous minerals are considered to have formed in the inner regions. Transport mechanisms from the inner to outer regions and olivine Mg# distributions of Y-980115, Ryugu samples, and comet Wild2 particles are discussed.
