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An Online Application for ΔR Calculation

Published online by Cambridge University Press:  29 December 2016

Ron W Reimer*
Affiliation:
14CHRONO Centre for Climate, the Environment and Chronology, Queen’s University Belfast, Belfast BT7 1NN, UK.
Paula J Reimer*
Affiliation:
14CHRONO Centre for Climate, the Environment and Chronology, Queen’s University Belfast, Belfast BT7 1NN, UK.
*
*Corresponding authors. Emails: r.reimer@qub.ac.uk; p.j.reimer@qub.ac.uk.
*Corresponding authors. Emails: r.reimer@qub.ac.uk; p.j.reimer@qub.ac.uk.

Abstract

A regional offset (ΔR) from the marine radiocarbon calibration curve is widely used in calibration software (e.g. CALIB, OxCal) but often is not calculated correctly. While relatively straightforward for known-age samples, such as mollusks from museum collections or annually banded corals, it is more difficult to calculate ΔR and the uncertainty in ΔR for 14C dates on paired marine and terrestrial samples. Previous researchers have often utilized classical intercept methods that do not account for the full calibrated probability distribution function (pdf). Recently, Soulet (2015) provided R code for calculating reservoir ages using the pdfs, but did not address ΔR and the uncertainty in ΔR. We have developed an online application for performing these calculations for known-age, paired marine and terrestrial 14C dates and U-Th dated corals. This article briefly discusses methods that have been used for calculating ΔR and the uncertainty and describes the online program deltar, which is available free of charge.

Type
Method Development
Copyright
© 2016 by the Arizona Board of Regents on behalf of the University of Arizona 

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Footnotes

Selected Papers from the 8th Radiocarbon & Archaeology Symposium, Edinburgh, UK, 27 June–1 July 2016

References

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