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Misunderstandings Concerning the Significance of AMS Background 14C Measurements

Published online by Cambridge University Press:  30 May 2018

R E Taylor ,
John R Southon  and
Guaciara M Santos Open the ORCID record for Guaciara M Santos [Opens in a new window]
R E Taylor*
Affiliation:
Department of Anthropology, University of California, Riverside, California 92521, USA and Cotsen Institute of Archaeology, University of California, Los Angeles, CA 90021, USA Keck Carbon Cycle Accelerator Mass Spectrometry Laboratory, Department of Earth System Science, University of California, Irvine, CA 92697, USA
John R Southon
Affiliation:
Keck Carbon Cycle Accelerator Mass Spectrometry Laboratory, Department of Earth System Science, University of California, Irvine, CA 92697, USA
Guaciara M Santos
Affiliation:
Keck Carbon Cycle Accelerator Mass Spectrometry Laboratory, Department of Earth System Science, University of California, Irvine, CA 92697, USA
*
*Coresponding author. Email: [email protected].
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Abstract

We consider one misconception of those who currently reject the general validity of radiocarbon (14C) age determinations older than, at most, 10,000 BP. There is an allegation that the presence of 14C reported by accelerator mass spectrometry (AMS) laboratories in their measurements of 14C infinite age (>100,000 years) organics used to define background levels, support their point of view. This article has been written for a general audience, primarily for those who have questions about the validity of these arguments. However, they may not be familiar with the literature relevant to providing a clear response to the claims of these individuals. We conclude that, in our view, of all of the possible explanations for the reports of the presence of 14C in these background samples, the least probable explanation has been advanced by those rejecting the validity of the 14C time scale in excess of, at most, 10,000 BP.

Keywords

14CAMSbackgrounds
Type
Case Study
Information
Radiocarbon , Volume 60 , Issue 3 , June 2018 , pp. 727 - 749
Copyright
© 2018 by the Arizona Board of Regents on behalf of the University of Arizona 

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