Chemical compositions of matrices of unequilibrated ordinary chondrites

• Main Authors: Yukio Ikeda, Makoto Kimura, Hiroshi Mori, Hiroshi Takeda
• Format: Report
• Language: English
• Published: Department of Earth Sciences, Ibaraki University/Department of Earth Sciences, Ibaraki University/Mineralogical Institute, Faculty of Science, University of Tokyo/Mineralogical Institute, Faculty of Science, University of Tokyo 1981
• Subjects: Memoirs of National Institute of Polar Research; Polar Research
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=1209; http://id.nii.ac.jp/1291/00001209/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=1209&item_no=1&attribute_id=18&file_no=1

The matrices of six unequilibrated O chondrites and one C chondrite, ALH-764 (LL3), Y-74191 (L3), ALH-77015 (L3), ALH-77033 (L3), ALH-77249 (L3), ALH-77299 (H3) and ALH-77003 (C3), were analyzed and classified into types I and II on the basis of their chemical compositions. The bulk chemical composition of the type I matrix is represented roughly by mixtures of ferrous olivine and sodic plagioclase. The type II matrix resembles the matrices of C2 and C3 chondrites in chemical composition.