論文

査読有り
2021年3月

Incorporation of U, Pb and Rare Earth Elements in Calcite through Crystallisation from Amorphous Calcium Carbonate: Simple Preparation of Reference Materials for Microanalysis

GEOSTANDARDS AND GEOANALYTICAL RESEARCH
  • Yusuke Miyajima
  • ,
  • Ayaka Saito
  • ,
  • Hiroyuki Kagi
  • ,
  • Tatsunori Yokoyama
  • ,
  • Yoshio Takahashi
  • ,
  • Takafumi Hirata

45
1
開始ページ
189
終了ページ
205
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1111/ggr.12367
出版者・発行元
WILEY

Uncertainty for elemental and isotopic measurements in calcite by LA-ICP-MS is largely controlled by the homogeneity of the reference materials (RMs) used for calibration and validation. In order to produce calcite RMs with homogeneous elemental and isotopic compositions, we incorporated elements including U, Pb and rare earth elements into calcite through heat- and pressure-induced crystallisation from amorphous calcium carbonate that was precipitated from element-doped reagent solution. X-ray absorption spectra showed that U was present as U(VI) in the synthesised calcite, probably with a different local structure from that of aqueous uranyl ions. The uptake rate of U by our calcite was higher in comparison with synthetic calcite of previous studies. Variations of element mass fractions in the calcite were better than 12% 2RSD, mostly within 7%. The Pb-207/Pb-206 ratio in the calcite showed < 1% variations, while the U-238/Pb-206 ratio showed 3-24% variations depending on element mass fractions. Using the synthetic calcite as primary RMs, we could date a natural calcite RM, WC-1, with analytical uncertainty as low as < 3%. The method presented can be useful to produce calcite with controlled and homogeneous element mass fractions and is a promising alternative to natural calcite RMs for U-Pb geochronology.

リンク情報
DOI
https://doi.org/10.1111/ggr.12367
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000597241100001&DestApp=WOS_CPL
ID情報
  • DOI : 10.1111/ggr.12367
  • ISSN : 1639-4488
  • eISSN : 1751-908X
  • Web of Science ID : WOS:000597241100001

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