Exploring the multicollection approach for the40Ar/39Ar dating technique
Autor: | Xavier Quidelleur, E. Coulié, J. C. Lefevre, Pierre-Yves Gillot |
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Rok vydání: | 2004 |
Předmět: |
Reproducibility
Argon 010504 meteorology & atmospheric sciences Mineralogy Faraday cup chemistry.chemical_element 010502 geochemistry & geophysics Mass spectrometry 01 natural sciences law.invention symbols.namesake Geophysics Data acquisition chemistry Geochemistry and Petrology Absolute dating law Neutron flux symbols Faraday cage Geology 0105 earth and related environmental sciences |
Zdroj: | Geochemistry, Geophysics, Geosystems. 5 |
ISSN: | 1525-2027 |
DOI: | 10.1029/2004gc000773 |
Popis: | We present an original analytical system for 40Ar/39Ar dating. It makes use of a 180° sector multicollection mass spectrometer equipped with five Faraday cups, which renders peak switching unnecessary during argon isotopic analyses. Compared to the single-collector approach commonly used for argon isotopic analyses, our system presents greater stability during data acquisition. Faraday cup efficiencies, which can be a limiting factor for the multicollection mass spectrometer, were highly reproducible. The analytical validity of the 40Ar/39Ar ages obtained using this new mass spectrometer has been preliminarily tested using geological standard minerals (MMhb-1, FCT-San, and HD-B1) commonly used as neutron fluence monitors. Independent plateau age determinations of Ethiopian samples duplicated over a 1-year interval demonstrated the reproducibility of the analyses. The results of these measurements highlight the good behavior of this new instrument for 40Ar/39Ar step heating dating. The age reproducibility of successive steps leads to analytical errors lower than 0.1% for well-behaved samples. This system, still in its initial stage of development, represents an alternative solution that is worth exploring in order to improve absolute dating by the 40Ar/39Ar technique. |
Databáze: | OpenAIRE |
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