加速器質量分析（ＡＭＳ）法による｀１４´Ｃ年代測定の高精度化および正確度向上の検討

• 中村 俊夫

  名古屋大学年代測定資料研究センター

書誌事項

タイトル別名

• An Investigation of High-Precision and High-Accuracy 14C Dating Using Accelerator Mass Spectrometry.
• カソクキ シツリョウ ブンセキ AMS ホウ ニヨル 14C ネンダイ ソクテ

抄録

Radiocarbon (¹⁴C) dating, known since 1950, is now used widely for research in geology, earth science, environmental science, archaeology, and cultural properties science. Conventionally, radioactivity measurements made by detecting beta-rays emitted in the radioactive decay of ¹⁴C atoms have been used to evaluate the ¹⁴C abundance of sample materials. About fifteen years ago, however, a new method of ¹⁴C dating by accelerator mass spectrometry (AMS) was developed, which uses a combination of a tandem electrostatic accelerator, a mass-analyzing magnet, and a heavyion detector, to detect ¹⁴C atoms directly and therefore requires very small amounts of carbon containing material, i. e., about 1mg of carbon, about three orders of magnitude less than that necessary for conventional radioactivity measurements. This outstanding performance has enabled us to apply ¹⁴C dating in various new areas of investigation.<br>This paper focuses on how to obtain highprecision and high-accuracy ¹⁴C dates. First, results of ¹⁴C dating with a Tandetron accelerator mass spectrometer at Nagoya University are briefly described. Also discussed are technical and theoretical issues in obtaining highlyreliable ¹⁴C ages with AMS: i. e.; collecting carbonaceous samples and preparing them without modern carbon contamination; selecting carbonaceous compounds particularly suitable for ¹⁴C dating; measuring ¹⁴C concentrations accurately and precisely with AMS; calculating ¹⁴C ages properly by correcting the ¹⁴C concentrations for carbon-isotopic fractionation; and calibrating ¹⁴C ages to calendar dates using dendrochronological data. In addition, two examples are discussed where AMS ¹⁴C dates for volcanic samples are compared with the dates measured for the relevant sample materials by fission-track and potassium-argon (K-Ar) dating methods. Finally, the present status of the Nagoya University Tandetron AMS facility and future plans for reforming the facility are described.

収録刊行物

• 第四紀研究

  第四紀研究 34 (3), 171-183, 1995

  日本第四紀学会

キーワード

• ¹⁴C年代測定
• 加速器質量分析
• 高精度化
• 正確度の向上
• 同位体分別
• 暦年代較正

詳細情報

• CRID: 1390282681473597056
• NII論文ID: 10002632864
• NII論文ID: 10003562519
• NII論文ID: 10003565887
• NII書誌ID: AN0034136X
• DOI: 10.4116/jaqua.34.171
• ISSN: 18818129
• ISSN: 04182642
• NDL書誌ID: 3624178
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I3624178
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可