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

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 N 2 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 (2σ) 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). Zircon, U-Pb age, trace element, uncertainty, LA-ICP-MS Citation: Liu Y S, Hu Z C, Zong K Q, et al. Reappraisement and refinement of zircon U-Pb isotope and trace element analyses by LA-ICP-MS.

Zircon U–Pb, molybdenite Re–Os and muscovite Ar–Ar isotopic dating of the Xitian W–Sn polymetallic deposit, eastern Hunan Province, South China and its geological significance

“…The ablated material was carried by He-Ar gas via a custom-made Squid system to homogenize the signal to the ICPMS (Liang et al, 2009). Raw data were processed using a timedrift correction and quantitative calibration and U-Pb dating were established using an in-house program ICPMSDataCal (Liu et al, 2010). External standard glass NIST SRM 610 (Pearce et al, 1997;Gao et al, 2002) and standard zircon Temora (Black et al, 2003) were used for external calibration.…”

A ∼2.5 Ga magmatic event at the northern margin of the Yangtze craton: Evidence from U-Pb dating and Hf isotope analysis of zircons from the Douling Complex in the South Qinling orogen

“…TEMORA zircon standard was used as an external standard for U-Pb dating. Data processing was completed using ICPMSDataCal [32,33] and ISOPLOT [34]. The conventional 208 Pb correction was performed.…”

Spatial Distribution and Influence Analysis of Soil Heavy Metals in a Hilly Region of Sichuan Basin

“…The second source was from industrial activity such as vehicular transport [24,[27][28]. The third source was controlled by the anthropogenic inputs from agricultural production, such as chemical fertilizers [29][30].…”

“…Annual Cd input to agricultural soil in China has been reported as 113, 778, and 30t for total fertilizers, livestock manures, and irrigation water, respectively [30]. Additionally, Zn and Zn compounds are widely used as agricultural fertilizers, and cattle slurry contains a significant amount of Zn and Cu since these elements are fed to cattle as a trace metal supplement [29,39]. In the research area, enrichment of heavy metals (Cd, Cu, and Zn) had a good correlation with the production of rice, and in turn rice production has a direct relationship with fertilizer use.…”