The Antarctic achondrite ALHA 76005 - A polymict eucrite

• Main Authors: Grossman, L., Davis, A. M., Tanaka, T., Macpherson, G. J., Olsen, E.
• Format: Other/Unknown Material
• Language: unknown
• Published: 1981
• Subjects: 91; Antarctic; The Antarctic; Antarc*
• Online Access: http://ntrs.nasa.gov/search.jsp?R=19810059377

ALHA 76005 is a basaltic achondrite containing few, if any, orthopyroxenes. Its bulk major and trace element composition is like that of a non-cumulate eucrite, and unlike that of a howardite. It contains a variety of igneous clasts which differ in their textures, pyroxene/plagioclase ratios and pyroxene and plagioclase compositions. One clast, No. 4, was found to have the REE pattern of a cumulate eucrite and an oxygen isotopic composition different from that of the bulk meteorite. Both the chemical and oxygen isotopic composition of clast No. 4 suggest that it was derived from a source different from its host. These observations lead to the conclusion that ALHA 76005 is a polymict eucrite.