Estimation of the environment to form hydrothermal veins of dark inclusion in the NWA2900 CK chondrite

Abstract

Dark Inclusion (DI) in NWA 2900 CK3 consists mainly of olivine, magnetite and plagioclase with large veins of diopside. Thermodynamic calculations indicates that the mineral assemblages observed in this dark inclusion can be obtained at temperature higher than 700C during high temperature aqueous alteration. This indicates that the dark inclusion experienced hydrothermal alteration with super critical water. Therefore, the presence of the DI with such diopside veins implies that a large and hot hydrous primordial asteroid was present in the early solar system.