Carbonaceous Chondrite Fragments in the Polymict Eucrite
نویسندگان
چکیده
Introduction: Buchanan et al. [1] and Zolensky et al. [2] described carbonaceous chondrite fragments in a variety of howardites and concluded that the majority are CM2 and CR2 materials. Gounelle et al. [3] also described similar, but very small, fragments in these meteorites. These clasts are important because they represent materials that were in orbital proximity to the HED parent body (4 Vesta) and they may be similar to the primitive materials that originally accreted to form this body [2]. The present study describes two carbonaceous chondrite clasts in the Yamato 791834 (Y791834) polymict eucrite. Opaque minerals include oxides and sulfides. Pentlandite contains significant, but small, proportions of Co and Pb (Table 1). Pyrrhotite contains Ni and significant amounts of Co and Pb (Table 1). Magnetite occurs as relatively large, rounded to polygonal grains, which are reminiscent of plaquettes in CI and CR meteorites. This magnetite is almost pure Fe3O4 with minimal proportions of other components. Carbonates were not found.
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