QUANTITATIVE-ANALYSIS OF ORIGINAL AND POWDERED ROCKS AND MINERAL INCLUSIONS BY LASER ABLATION INDUCTIVELY COUPLED PLASMA MASS-SPECTROMETRY

Direct analysis of rocks by laser ablation inductively coupled plasma mass spectrometry is described. Both powdered standard rocks and the original rocks were analysed and the results agreed with each other in spite of the difference in the surface states. Microprobe analysis of biotite in granite JG1 was also done directly with a focused laser beam and the results obtained were very close to the solution values given by the conventional aqueous method using biotite separated from an original rock. For quantitative analysis, the measured signal intensity was normalized either by the ablated weight or the barium signal intensity. Forty-two major and minor elements (two of them being used as internal standards) in twelve standard rocks fromt the igneous rock series of the Geological Survey of Japan were determined successfully. © 1990.