Mössbauer spectroscopic study of meteorites recovered on Antarctica

The chemical states of iron in sixteen Antarctic meteorites belonging to H-group chondrites were studied by means of Mossbauer spectroscopy. An Fe-Ni alloy, troilite, paramagnetic Fe(III), and two kinds of paramagnetic Fe(II) were observed in each meteorite. The Mossbauer parameters indicated that the Fe(II) components can be assigned to olivine and some pyroxenes. The relative area intensities of Fe(III) in the chondrites correlated positively with iodine content, which was determined by radiochemical neutron activation analysis, and those of two Fe(II)-species correlated negatively with the content. On the basis of the data on the halogen and the Mossbauer spectrocopy, the terrestrial contamination on Antarctic meteorites is discussed.