Impactor Type and Model of the Origin of the Zhamanshin Astrobleme, Kazakhstan

Resumo

Fragments of heterogeneous cosmonegic substance (nickelphosphide Ni₃P and ZnAl₂) were found using high resolution analytical electron microscopic techniques, for the first time in samples from a large meteorite crater: the Zhamanshin astrobleme in Kazakstan. Inasmuch as such fragments cannot simultaneously occur in meteorite of any one type, we suggest that the impactor of the Zhamanshin crater was of comet nature.