Carbon components and their isotopic compositions in the Allende meteorite.

Abstract

High-resolution stepwise oxidations on two bulk fractions and an acid residue show the existence of at least three carbon phases and suggest the possible presence of two more. The bulk of the carbon has a peak release T closely corresponding with amorphous (free) C and an isotopic composition of approx -20per mille. A minor component with a low delta 13C value may be present, possibly correlated with either N or Xe components. -B.M.