We introduce a potential new working reference material – natural zircon megacrysts from an Early Pliocene alkaline basalt (from Penglai, northern Hainan Island, southern China) – for the microbeam determination of O and Hf isotopes, and U–Pb age dating. The Penglai zircon megacrysts were found to be fairly homogeneous in Hf and O isotopes based on large numbers of measurements by LA‐multiple collector (MC)‐ICP‐MS and SIMS, respectively. Precise determinations of O isotopes by isotope ratio mass spectrometry (IRMS) and Hf isotopes by solution MC‐ICP‐MS were in good agreement with the statistical mean of microbeam measurements. The mean δ18O value of 5.31 ± 0.10‰ (2s) by IRMS and the mean 176Hf/177Hf value of 0.282906 ± 0.0000010 (2s) by solution MC‐ICP‐MS are the best reference values for the Penglai zircons. SIMS and isotope dilution‐TIMS measurements yielded consistent 206Pb/238U ages within analytical uncertainties, and the preferred 206Pb/238U age was found to be 4.4 ± 0.1 Ma (95% confidence interval). The young age and variably high common Pb content make the Penglai zircons unsuitable as a primary U–Pb age reference material for calibration of unknown samples by microbeam analysis; however, they can be used as a secondary working reference material for quality control of U–Pb age determination for young (particularly < 10 Ma) zircon samples.

No abstract

No abstract

LA-ICP-MS and LA-MC-ICP-MS have been the techniques of choice for achieving accurate and precise element content and isotopic ratio, the state-of-the-art technique combines the advantages of low detection limits with high spatial resolution, however, the analysis accuracy and precision are restricted by many factors, such as sensitivity drift, elemental/isotopic fractionation, matrix effects, interferences and the lack of sufficiently matrix-matched reference materials. Thus, rigorous and suitable calibration and correction methods are needed to obtain quantitative data. This review systematically summarized and evaluated the interference correction, quantitative calculation and sensitivity correction strategies in order to provide the analysts with suitable calibration and correction strategies according to the sample types and the analyzed elements. The functions and features of data reduction software ICPMSDataCal were also outlined, which can provide real-time and on-line data reduction of element content and isotopic ratios analyzed by LA-ICP-MS and LA-MC-ICP-MS.

High-grade pelitic metasedimentary rocks (khondalites) are widely distributed in the northwestern part of the North China Craton and were named the 'Khondalite Belt'. Prior to the application of zircon geochronology, a stratigraphic division of the supracrustal rocks into several groups was established using interpretative field geology. We report here SHRIMP U-Pb zircon ages and Hf-isotope data on metamorphosed sedimentary and magmatic rocks at

A comprehensive method for the precise determination of Re, Os, Ir, Ru, Pt and Pd concentrations as well as Os isotopic compositions in geological samples is presented. Samples were digested by the Carius tube method, and the Os was extracted by conventional CCl 4 method. The Re, Ir, Ru, Pt and Pd were first subgroup separated from the matrix elements into Re-Ru, Ir-Pt and Pd by a 2-ml anion exchange column. Subsequently, the Re-Ru was further purified by a secondary 0.25 ml anion exchange column or by microdistillation of Ru using CrO 3 -H 2 SO 4 as an oxidant followed by a secondary 0.25 ml anion exchange separation of Re. The Pd and Ir-Pt were further successively purified by an Eichrom-LN column to completely remove Zr and Hf, respectively. Rhenium, Ir, Ru, Pt and Pd were individually measured by multi-collector inductively coupled plasmamass spectrometry (MC-ICP-MS), except for Ru after microdistillation purification was analysed by negativethermal ionisation mass spectrometry (N-TIMS). The analytical results for peridotite reference material WPR-1 agree well with the previously published data. Finally, several mafic rock reference materials including TDB-1, WGB-1, BHVO-2, BCR-2, BIR-1a and DNC-1a were analysed for Re-Os isotopes and platinum-group element concentrations to test their suitability for certification.The platinum-group elements (PGEs) (Rh, Ru, Pd, Os, Ir and Pt), Re and Os isotopic compositions have attracted considerable interest in geological sciences because they are important tracers for the understanding of mantle processes and evolution of the Earth (Shirey and Walker 1998). As a result, the accurate determination of the concentration of PGEs and Re along with Os isotopic compositions in geological materials is very important. Currently, N-TIMS Os isotopic analysis of low-level samples, such as mafic rocks with sub ng g -1 to pg g -1 abundances of Os, typically achieves precisions better than 0.2% 2 RSD for 187 Os/ 188 Os (Creaser et al. 1991, Volkening et al. and accurate determination of Re, Ir, Ru, Pt and Pd, especially for low abundance geological samples such as mafic rocks (typically Ir and Ru < 1 ng g -1 ), remains challenging.

Bastnaesite, a common accessory mineral in REE ore deposits, is ideal for U–Pb isotopic dating because of its relatively high U and Th contents.

An improved chemical method is developed to accurately measure the W isotopic compositions of silicate samples with a precision of better than ±0.05ε on ε182W.