MICRO-PIXE WITHIN MAGMATIC INCLUSIONS USING GUPIX SOFTWARE

We have specifically developed the micro-PIXE method in order to study trace elements in volcanic glasses and in melt inclusions trapped in minerals. The elements of interest are contained between Sc and Nb, th ese elements being useful tracers of the lava generation processes. Fo r this purpose, we adopted GUPIX software (Guelph PIXE software packag e) which seems suitable for analytical problems generally encountered in the geological field. Adaptations were made to the software to suit our specific requirements: measurement of the H factor as a function of X-ray energy for a thick sample, creation of a fitting program for determining the signal modelisation parameters vs X-ray energy. We obt ained reliable results, as proved through the utilization of reference materials (Soil7 and SL1) and samples of composition previously measu red by another technique. Fe was used as the internal standard. Micro- PIXE was applied to the study of the phenocryst melt inclusions from s everal geological contexts.