Mineralogy of CO3 chondrites using X-ray and EPMA: the formation and evolution of the parent body

Abstract

The powder X-ray diffractions of ten CO3s revealed that (1) the half width of olivine peak correlates with the subtype, (2) the increase of the subtype leads to the decrease of the intensity of low-Ca clinopyroxenes, due to the growth of the ferroan olivine in matrices, and (3) the peak intensity of taenite increases and that of tetrataenite newly also appears.  The peak temperature is estimated to be 800K and the diameter of the parent body is 30km.