TY - JOUR
T1 - Synthetic zircon doped with hafnium and rare earth elements
T2 - A reference material for in situ hafnium isotope analysis
AU - Fisher, Christopher M.
AU - Hanchar, John M.
AU - Samson, Scott D.
AU - Dhuime, Bruno
AU - Blichert-Toft, Janne
AU - Vervoort, Jeffery D.
AU - Lam, Rebecca
N1 - Funding Information:
CMF acknowledges the Mineralogical Society of America for funds received through the Grant for Student Research in Mineralogy and Petrology that helped support this research, as well as Henry Longerich for many helpful conversations regarding LA-ICPMS over the past four years. JMH thanks the Canadian Natural Sciences and Research Council (NSERC) for support for this research in the form of Discovery Grants, and the Memorial University of Newfoundland for additional financial support for this project. JB-T gratefully acknowledges financial support from the French Institut National des Sciences de l'Univers . B.D. gratefully acknowledges support from the NERC ( NE/E005225/1 ). Michael Power is thanked for his help with zircon syntheses. Mike Tubrett is thanked for his technical assistance throughout this project. Editor Laurie Reisberg and two anonymous reviewers are kindly thanked for their thorough and constructive reviews, which improved this manuscript.
PY - 2011/6/26
Y1 - 2011/6/26
N2 - A series of flux-grown synthetic zircon crystals doped with Hf and selected rare earth elements (REE) were produced for use as a potential reference material for Lu-Hf isotopic analysis of zircon by in situ laser ablation multi-collector inductively-coupled plasma mass spectrometry (LA-MC-ICPMS). The synthetic zircon crystals were doped such as to produce a large range of REE/Hf, allowing for a robust means of monitoring and correcting the sometimes large 176Yb and 176Lu isobaric interferences on the low-abundance 176Hf in natural zircon, as well as potential oxide interferences from Gd, Tb, and Dy. The synthetic zircon crystals have a homogeneous Hf isotopic composition, both within and between grains, as documented by solution MC-ICPMS analyses of Hf chemically separated from multiple fragments of zircon from three different syntheses, and 321 laser ablation MC-ICPMS analyses done in two different laboratories. An additional 110 in situ analyses of natural zircon crystals reveal identical behavior of natural and synthetic zircon during Hf isotope analysis by laser ablation. Hence, the synthetic zircon crystals provide a means of monitoring a wide range of Yb and Lu interferences (up to 50% of the total signal intensity at mass 176) during routine isotopic analysis for geological studies. They also may be helpful in developing improved laboratory protocols for accurate in situ Lu-Hf isotopic measurement of natural zircon. The present data illustrate the importance of the 176Yb interference correction on 176Hf, which can result in large biases if not properly applied to natural samples with their variable and often high 176Yb/177Hf. This study definitively shows that use of high-REE/Hf synthetic zircon standards for calibrating the Yb mass bias correction is more accurate than use of Yb-doped natural Hf solutions. Finally, the results of the present work suggest that synthetic minerals may prove useful as both in situ method development tools and isotopic reference materials.
AB - A series of flux-grown synthetic zircon crystals doped with Hf and selected rare earth elements (REE) were produced for use as a potential reference material for Lu-Hf isotopic analysis of zircon by in situ laser ablation multi-collector inductively-coupled plasma mass spectrometry (LA-MC-ICPMS). The synthetic zircon crystals were doped such as to produce a large range of REE/Hf, allowing for a robust means of monitoring and correcting the sometimes large 176Yb and 176Lu isobaric interferences on the low-abundance 176Hf in natural zircon, as well as potential oxide interferences from Gd, Tb, and Dy. The synthetic zircon crystals have a homogeneous Hf isotopic composition, both within and between grains, as documented by solution MC-ICPMS analyses of Hf chemically separated from multiple fragments of zircon from three different syntheses, and 321 laser ablation MC-ICPMS analyses done in two different laboratories. An additional 110 in situ analyses of natural zircon crystals reveal identical behavior of natural and synthetic zircon during Hf isotope analysis by laser ablation. Hence, the synthetic zircon crystals provide a means of monitoring a wide range of Yb and Lu interferences (up to 50% of the total signal intensity at mass 176) during routine isotopic analysis for geological studies. They also may be helpful in developing improved laboratory protocols for accurate in situ Lu-Hf isotopic measurement of natural zircon. The present data illustrate the importance of the 176Yb interference correction on 176Hf, which can result in large biases if not properly applied to natural samples with their variable and often high 176Yb/177Hf. This study definitively shows that use of high-REE/Hf synthetic zircon standards for calibrating the Yb mass bias correction is more accurate than use of Yb-doped natural Hf solutions. Finally, the results of the present work suggest that synthetic minerals may prove useful as both in situ method development tools and isotopic reference materials.
KW - Hafnium isotopes
KW - Isobaric interference
KW - Laser ablation
KW - Reference material
KW - Synthetic zircon
KW - Ytterbium
UR - http://www.scopus.com/inward/record.url?scp=79958010206&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79958010206&partnerID=8YFLogxK
U2 - 10.1016/j.chemgeo.2011.04.013
DO - 10.1016/j.chemgeo.2011.04.013
M3 - Article
AN - SCOPUS:79958010206
SN - 0009-2541
VL - 286
SP - 32
EP - 47
JO - Chemical Geology
JF - Chemical Geology
IS - 1-2
ER -