Reappraisement and refinement of zircon U-Pb isotope and trace element analyses by LA-ICP-MS

摘要: A protocol was established for simultaneous measurements of zircon U-Pb ages and trace elements by LA-ICP-MS at spot sizes 16–32 ?m. This accomplished introducing N2 into ICP to increase the sensitivity. The obtained standards GJ-1, TEMORA SK10-2 are consistent with preferred values within about 1% uncertainty (2 σ ) simple external calibration against standard 91500. Different data reduction softwares could yield different uncertainties calculation ages. commercially available program GLITTER4.4 apply an improper strategy, but it may artificial high precisions single analyses. Our element analyses indicate that Si is not ideal internal when calibrated NIST glasses. Calibration glasses using as standard, a systematic deviation 10%–30% found most including Zr. However, compositions can be accurately measured multiple reference materials natural (e.g., BCR-2G, BHVO-2G BIR-1G), or SRM 610 Zr standard. Analyses two pieces GJ-1 demonstrate relatively homogenous (except Ti).