Journal of the Korean earth science society (한국지구과학회지)

The Korean Earth Science Society (한국지구과학회)
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A Working Standard Technique far Determination of Interference Correction Factors and Preparation of Standard Materials for CHIME Dating

CHIME 연대 측정의 간섭 보정 계수 결정과 표준 물질의 준비를 위한 실험실 표준법

  • Cho, Deung-Lyong (Geology and Geoinformation Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Kato, Takenori (Center for Chronological Research, Nagoya University) ;
  • Suzuki, Kazuhiro (Center for Chronological Research, Nagoya University)
  • 조등룡 (한국지질자원연구원 지질기반정보연구부) ;
  • ;
  • Published : 2006.10.30
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Abstract

The EPMA analysis for CHIME dating requires standard materials, which include nuclear fuel materials that are rare and sensitive to handle. Any laboratory that does not meet these standards has had difficulties adopting the CHIME dating method. We have developed a working standard technique for CHIME dating to prepare standard materials without use of nuclear fuel materials. Mineral samples, such as small pieces of monazite that are homogeneous in X-ray intensities, are calibrated using well-characterized primary standards in one laboratory. Once this procedure is done, they can be readily usable as working standards in the other laboratories, only with measurement of X-ray intensities. This method is applicable in preparing standard materials for both chemical compositions and determination of X-ray interference correction factors, and it is independent from chemical composition of mineral standard.

CHIME 연대측정을 위한 전자현미분석(EPMA)에서는 통상적으로 핵 연료 물질 등 구하기 어렵고 관리에 민감한 표준 물질을 사용하므로 이를 구하지 못하는 실험실에서는 적용에 어려움이 있다. 이 연구에서는 이러한 표준 물질을 대신할 수 있는 새로운 실험실 표준법을 제시한다. CHIME 연대 측정이 원활하게 이루어지고 일련의 표준 물질이 잘 구비된 실험실에서 X선 세기가 균질함이 확인된 모나자이트와 같은 광물편을 대상으로 보정 상수를 정확히 구하고, Th, U 등의 특성 X선 세기를 측정해두면, 다른 실험실에서는 단지 광물편의 특성 X선 세기를 측정하는 것만으로 바로 사용할 수 있는 표준 물질로 활용할 수 있다. 이 기법은 전자 현미 분석에서 화학성분과 X선 간섭 보정 계수의 결정에 필요한 표준 물질로 모두 활용이 가능하며, 광물 표준 물질의 복잡한 화학 성분에 대해 독립적이다.

Keywords

References

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