Carbon,Oxygen, Silicon,Sulphur, Calcium,and Iron Determinations in Twenty-four Dark Clasts and One Dark Inclusion of the Allende Meteorite by 12C(d,p)13C Nuclear Reaction and PIXE

Abstract— A study of carbon contents of millimeter-sized dark clasts and of one dark inclusion of the Allende meteorite with the ¹³C(d,P₀)¹³C method has been undertaken. The results show that C in dark Allende areas varies, perhaps in a “clustered” fashion, from near 0.3%, which is essentially the bulk C-content of the meteorite, to at least 2.1% in the dark rim of a dark inclusion. At least one cluster has now been identified with C-contents in the range 0.4%-0.5%. Raman spectra of C in the dark inclusion ADIR 4E1-fu and in matrix have also been determined. These are identical. Our results are consistent with a comparatively low temperature origin of essentially all elemental carbon in Allende.