REE patterns versus the origin of the basaltic achondrites |
| |
Authors: | Guy J Consolmagno |
| |
Institution: | Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138 USA |
| |
Abstract: | The spectral uniqueness of asteroid 4 Vesta has led to suggestions that it is the eucrite parent body. However, there exist other basaltic achondrite types besides eucrites; either they also came from Vesta or else there exist other achondrite parent bodies. Howardites appear to be mixtures of eucrites and diogenites, and mesosiderites mixtures of eucrites or howardites and iron; thus one may infer that all four classes come from the same parent body. The REE patterns of eucrites and diogenites are modeled in order to test this hypothesis; eucrites can be made easily, but the patterns of diogenites are more difficult to match. The other basaltic achondrites are so rare that one cannot argue from statistics of abundances against a disrupted parent body for their origin. Pallasites and most irons likely had an origin separate from eucrites, again in parent bodies since disrupted. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|