Detection of terrestrial fluorine by proton induced gamma emission (PIGE): A rapid quantification for Antarctic meteorites

Abstract

The enrichment of fluorine on the surface of Antarctic meteorites is investigated by applying the nuclear reactions 19F(p, alpha x gamma)16O or 19F(p, p'gamma)19F with the proton induced gamma emission (PIGE) technique, a class of nuclear reaction analysis (NRA). Results for the Antarctic meteorites ALHA77294, TIL 82409, LEW 86015, ALHA77003, and ALH 83108 are presented. Possible sources of terrestrial F are: volcanic exhalation, tephra layers (volcanic glass), continental soil dust, or sea spray. Material from blue-ice dust-band samples also shows concentrations of F that are significantly higher than the bulk concentrations of meteorites. Finally, a quick investigation for Antarctic meteorites by external PIGE is proposed, leading to a F-contamination index that supplements the qualitative ABC-weathering index.