Reappraisement and refinement of zircon U-Pb isotope and trace element analyses by LA-ICP-MS |
| |
Authors: | YongSheng Liu ZhaoChu Hu KeQing Zong ChangGui Gao Shan Gao Juan Xu HaiHong Chen |
| |
Affiliation: | 1 State Key Laboratory of Geological Processes and Mineral Resources, Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China; 2 State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an 710069, China |
| |
Abstract: | A protocol was established for simultaneous measurements of zircon U-Pb ages and trace elements by LA-ICP-MS at spot sizes of 16–32 μm. This was accomplished by introducing N2 into ICP to increase the sensitivity. The obtained U-Pb ages for zircon standards GJ-1, TEMORA and SK10-2 are consistent with the preferred values within about 1% uncertainty (2 σ) by simple external calibration against zircon standard 91500. Different data reduction softwares could yield different uncertainties for calculation of U-Pb ages. The commercially available program GLITTER4.4 could apply an improper uncertainty calculation strategy, but it may yield artificial high precisions for single analyses. Our trace element analyses indicate that Si is not an ideal internal standard for zircon when calibrated against the NIST glasses. Calibration against the NIST glasses using Si as an internal standard, a systematic deviation of 10%–30% was found for most trace elements including Zr. However, the trace element compositions of zircon can be accurately measured by calibration against multiple reference materials with natural compositions (e.g., BCR-2G, BHVO-2G and BIR-1G), or calibration against NIST SRM 610 and using Zr as an internal standard. Analyses of two pieces of GJ-1 demonstrate that it is relatively homogenous for most trace elements (except for Ti). |
| |
Keywords: | Zircon U-Pb age trace element uncertainty LA-ICP-MS |
本文献已被 CNKI SpringerLink 等数据库收录! |
| 点击此处可从《科学通报(英文版)》浏览原始摘要信息 |
|
点击此处可从《科学通报(英文版)》下载全文 |
|