Zoned CaAl-rich chondrule in Bali: New evidence against the primordial condensation model

One large (8.5 mm) chondrule in the Bali carbonaceous chondrite is strongly enriched in refractory elements similarily to the white objects in Allende which are widely believed to be “primitive” condensates. However, detailed investigations show the Bali chondrule to have an element distribution opposite to that predicted by the “primitive condensation” models. Refractory elements like Ti and Al are enriched at or near the surface of the chondrule. The contents of some volatile elements, e.g. Na, Si, and Cr, are higher in the central portion. It is suggested that this chondrule - and similar objects in other C-chondrites - originated in one, or more likely several, impact events and that the element distribution is the result of volatilization-condensation.