Comprehensive Pb‐Sr‐Nd‐Hf isotopic, trace element, and mineralogical characterization of mafic to ultramafic rock reference materials

Abstract

Controlling the accuracy and precision of geochemical analyses requires the use of characterized reference materials with matrices similar to those of the unknown samples being analyzed. We report a comprehensive Pb‐Sr‐Nd‐Hf isotopic and trace element concentration data set, combined with quantitative phase analysis by XRD Rietveld refinement, for a wide range of mafic to ultramafic rock reference materials analyzed at the Pacific Centre for Isotopic and Geochemical Research, University of British Columbia. The samples include a pyroxenite (NIM‐P), five basalts (BHVO‐2, BIR‐1a, JB‐3, BE‐N, GSR‐3), a diabase (W‐2), a dolerite (DNC‐1), a norite (NIM‐N), and an anorthosite (AN‐G); results from a leucogabbro (Stillwater) are also reported. Individual isotopic ratios determined by MC‐ICP‐MS and TIMS, and multielement analyses by HR‐ICP‐MS are reported with 4–12 complete analytical duplicates for each sample. The basaltic reference materials have coherent Sr and Nd isotopic ratios with external precision below 50 ppm (2SD) and below 100 ppm for Hf isotopes (except BIR‐1a). For Pb isotopic reproducibility, several of the basalts (JB‐3, BHVO‐2) require acid leaching prior to dissolution. The plutonic reference materials also have coherent Sr and Nd isotopic ratios (<50 ppm), however, obtaining good reproducibility for Pb and Hf isotopic ratios is more challenging for NIM‐P, NIM‐N, and AN‐G due to a variety of factors, including postcrystallization Pb mobility and the presence of accessory zircon. Collectively, these results form a comprehensive new database that can be used by the geochemical community for evaluating the radiogenic isotope and trace element compositions of volcanic and plutonic mafic‐ultramafic rocks.

Hf–Nd isotope decoupling in bulk abyssal peridotites due to serpentinization

“…We are unaware of other Sr isotope determinations of PCC-1. The BIR-1 Hf and Nd isotope compositions acquired with this method fall within previously published values (Bizzarro et al, 2003;Le Fevre and Pin, 2005;Chu et al, 2009;Hoffmann et al, 2010;Fourny et al, 2016).…”

The Size and Emergence of Geochemical Heterogeneities in the Hawaiian Mantle Plume Constrained by Sr‐Nd‐Hf Isotopic Variation Over ∼47 Million Years

“…USGS Reference Material BCR-2 was used for external calibration and a 1 ppb In spike was used as an internal standard. RSDs are less than 5% for all elements and measured concentrations of USGS Standard BHVO-2 are within 2SD of published values (e.g.,Fourny et al, 2016). Detailed analytical techniques are presented in the supporting information.10.1029/2017GC007389Geochemistry, Geophysics, Geosystems enriched in REE than those from Mauna Kea (shown by gray field inFigure 5), except for samples from Gardner, Northampton, Twin Banks, and Nīhoa.…”

GGR Biennial Critical Review: Analytical Developments Since 2014

“…The mafic to ultramafic rock RMs NIM‐P, BHVO‐2, BIR‐1a, JB‐3, BE‐N, GSR‐3, W‐2, DNC‐1, NIM‐N, AN‐G are now well characterised for Pb‐Sr‐Nd‐Hf isotopes (Fourny et al . ).…”

“…Using a precision expressed as 2SE they partly disagree, where the authors interpret this inconsistency in Ca isotopes to measurement bias and/or sample heterogeneity. The mafic to ultramafic rock RMs NIM-P, BHVO-2, BIR-1a, JB-3, BE-N, GSR-3, W-2, DNC-1, NIM-N, AN-G are now well characterised for Pb-Sr-Nd-Hf isotopes (Fourny et al 2016).…”