DETERMINATION OF PARTITION-COEFFICIENTS FOR TRACE-ELEMENTS IN HIGH-PRESSURE TEMPERATURE EXPERIMENTAL RUN PRODUCTS BY LASER-ABLATION MICROPROBE INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY (LAM-ICP-MS)

This paper reports the first trace element partition coefficients measured on experimentally produced products (clinopyroxene, garnet, rutile, and glass) by laser ablation microprobe-inductively coupled plasma-mass spectrometry (LAM-ICP-MS). A 266 nm (UV) laser microprobe was used to improve ablation characteristics and to achieve a fourfold reduction in ablation pit diameter compared to the previously used 1064 nm beam. Results are compared with PIXE analyses on the same experimental products, and literature values, where available, for similar systems, and include the first simultaneously measured partition coefficients for Zr, Nb, and Ta between rutile and glass. Advantages of the LAM technique include rapid results and simultaneous determination of a wide range of major and trace elements, thus ensuring sampling integrity through time-resolved analysis of the sampled material.