The systematic investigation of high-pressure polymorphs in ordinary chondrites

Abstract

High-pressure polymorphs formed in H-, L- and LL-type ordinary chondrites (OCs) were systematically investigated with FE-SEM and Raman spectroscopy. Many high-pressure polymorphs occur in the shock melting texture of both L- and LL-type OCs, whereas few in H-type OCs. Although many kinds of high-pressure polymorphs occur in petrologic type 6, only Na-pyroxene occur as the replacement of plagioclase or chondritic glass in petrologic type 3-5. The abundance and species of high-pressure polymorphs are closely related with the species of OCs and petrologic types.