PIXE and light element analysis (C,N) in glass inclusions trapped in meteorites with the nuclear microprobe

Proton-induced X-ray emission (PIXE) and light element analysis have been p erformed with the nuclear microprobe at the Laboratoire Pierre Sue (Saclay- France) in glass inclusions of the carbonaceous chondrites: Allende, Kaba a nd Renazzo, and in the achondrite meteorite: Chassigny. Carbon contents in olivine of chondrules are below the nuclear reactions analysis (NRA) detect ion limit, however, glasses from glass inclusions hosted by these grains, c ontain an appreciable and highly variable quantities of carbon (200-1600 pp m). This could indicate variable amounts of C trapped during glass inclusio n formation. On the other hand; nitrogen is present in highly variable amou nts in glasses of both, chondrites and achondrites minerals. Its abundance, correlated with depth from the section surface which suggests loss of N du ring analyses and therefore the possible existence of a very mobile (volati le?) species. A chondritic Rb/Sr and K/Rb ratio obtained by PIXE analyses i n the glass-bearing inclusions of the Chassigny meteorite points towards a primitive source for the glass precursor of Chassigny inclusions. (C) 1999 Elsevier Science B.V. All rights reserved.