3:30 PM - 3:45 PM
[SGC50-06] Single shot laser ablation-multiple collection-ICP-mass spectrometry for U-Pb age
Keywords:LA-MC-ICPMS, U-Pb age, zircon, single shot, elemental fractionation, aspect ratio
The shallower ablation pit could be obtained when a smaller number of laser shots were adopted. To achieve this, a multiple collector-ICPMS was adopted to the U-Pb age determinations. With the multiple collector system, precision in the isotope ratio measurements can be improved even from the transient signals produced by the smaller number of laser shots. Hence, six isotopes were monitored by the six independent multipliers ; 202Hg (IC), 204Pb (IC), 206Pb (IC), 207Pb (IC), 208Pb (IC), 232Th (F) and 235U or 238U (IC).
Three natural zircons (OD-34), Plesovice5) and GJ-16)) were employed to evaluate the reliability of the resulting U-Pb ages. Nancy 915007) zircon was used as a calibration standard for the Pb/U ratio measurements. The glass standard (NIST SRM 610) was used for the calibration in the 207Pb/206Pb isotope ratio measurements. Laser ablation system used in this study was a New Wave Research femto laser ablation system (Fremont, CA 94538, USA), and the ICPMS instrument used in this study was a Nu Instruments (Wrexham, UK) Nu Plasma II multi-collector ICPMS. For comparison, U-Pb ages were also measured by the single collector-ICPMS instrument (Nu Instruments AttoM). In our presentation, we will demonstrate the high analytical capability of the MC-ICPMS technique from the single shot laser sampling.
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