Nuclear reaction microanalysis and electron microanalysis of light elements in minerals and glasses

Abstract Electron microprobe analysis (EMA) and nuclear microanalysis (NMA) have been used to determine light elements ( Z ⩽ 30) in minerals and glasses. Optimum NMA reaction conditions for the detection of various elements are presented and detection limits are estimated for both micro- and macrobeams. A comparison is made between results of EMA and NMA analyses for several elements. Peculiarities of both methods are emphasized. While EMA is convenient in fast routine measurement for most elements in the periodic table above Na, with analytical sensitivities ranging from 100 to 1000 wt. ppm, NMA in charged-particle or prompt gamma-ray nuclear reaction analysis (NRA) mode allows the analysis of all the isotopes between 1 H and 19 F (except 4 He and 20 Ne), with a sensitivity often better than 50 ppm. In addition, proton-induced gamma-ray emission (PIGE) enables the determination of heavier elements (from Na to Zn) with relatively good performances. Furthermore, depth profiling and local isotopic ratio measurements constitute some new interesting applications for NMA.