Howardites and Mesosiderites: Contrasting Polymict Breccias from Two Similar Differentiated Asteroids

[摘要] Silicates in mesosiderites commonly show anomalous characteristics compared to howardites. These characteristics indicate that many of the mesosiderite lithologies were formed during and/or after metal silicate mixing. Petrologic evidence indicates that impact gardening occurred on the mesosiderite asteroid after metal-silicate mixing. Thus the anomalous materials ought to be widely distributed on that asteroid. The compositions of howardites suggest a well-mixed regolith on Vesta. The lack of distinctive mesosiderite-like materials in howardites favors separate parents for the two meteorite groups.

[发布日期] 2014-09-07

[学科分类] 地质物理学