| Popis: |
The compositions of the mineral components of two inclusions within a CM-like clast in the Plainview (H5) chondrite are determined. The inclusions have the morphologies of an Allende-like, coarse-grained CAI and an amoeboid olivine inclusion, respectively. Major constituents of the altered inclusions are found to be calcite, Mg-Fe-rich phyllosilicates, Fe-Ti oxides, and an Al-rich phyllosilicate, and it is suggested that the alteration process would have required transport of Ne, Cl, H2O, CO2, and FeO. Liquid water appears to be the medium in which the alterations took place, due to the presence of hydrous phases and significant quantities of iron required to produce the mineral assemblages now present from the inferred starting materials. |
