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Zircon M127 – A Homogeneous Reference Material for SIMS U–Pb Geochronology Combined with Hafnium, Oxygen and, Potentially, Lithium Isotope Analysis
Author(s) -
Nasdala Lutz,
Corfu Fernando,
Valley John W.,
Spicuzza Michael J.,
Wu FuYuan,
Li QiuLi,
Yang YueHeng,
Fisher Chris,
Münker Carsten,
Kennedy Allen K.,
Reiners Peter W.,
Kronz Andreas,
Wiedenbeck Michael,
Wirth Richard,
Chanmuang Chutimun,
Zeug Manuela,
Váczi Tamás,
Norberg Nicholas,
Häger Tobias,
Kröner Alfred,
Hofmeister Wolfgang
Publication year - 2016
Publication title -
geostandards and geoanalytical research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.037
H-Index - 73
eISSN - 1751-908X
pISSN - 1639-4488
DOI - 10.1111/ggr.12123
Subject(s) - zircon , geochronology , hafnium , metamictization , analytical chemistry (journal) , lithium (medication) , radiogenic nuclide , isotope , homogeneous , isotopes of oxygen , geology , mineralogy , radiochemistry , chemistry , zirconium , geochemistry , physics , nuclear physics , environmental chemistry , inorganic chemistry , mantle (geology) , thermodynamics , medicine , endocrinology
In this article, we document a detailed analytical characterisation of zircon M127, a homogeneous 12.7 carat gemstone from Ratnapura, Sri Lanka. Zircon M127 has TIMS ‐determined mean U–Pb radiogenic isotopic ratios of 0.084743 ± 0.000027 for 206 Pb/ 238 U and 0.67676 ± 0.00023 for 207 Pb/ 235 U (weighted means, 2 s uncertainties). Its 206 Pb/ 238 U age of 524.36 ± 0.16 Ma (95% confidence uncertainty) is concordant within the uncertainties of decay constants. The δ 18 O value (determined by laser fluorination) is 8.26 ± 0.06‰ VSMOW (2 s ), and the mean 176 Hf/ 177 Hf ratio (determined by solution ICP ‐ MS ) is 0.282396 ± 0.4 (2 s ). The SIMS ‐determined δ 7 Li value is −0.6 ± 0.9‰ (2 s ), with a mean mass fraction of 1.0 ± 0.1 μg g −1 Li (2 s ). Zircon M127 contains ~ 923 μg g −1 U. The moderate degree of radiation damage corresponds well with the time‐integrated self‐irradiation dose of 1.82 × 10 18 alpha events per gram. This observation, and the (U–Th)/He age of 426 ± 7 Ma (2 s ), which is typical of unheated Sri Lankan zircon, enable us to exclude any thermal treatment. Zircon M127 is proposed as a reference material for the determination of zircon U–Pb ages by means of SIMS in combination with hafnium and stable isotope (oxygen and potentially also lithium) determination.