On the relationship between radiocarbon dates and true sample ages.

Abstract

A summary is given of current knowledge pertaining to differences between radiocarbon ages and true ages and of the status of empirical calibration of the radiocarbon time scale. Recent measurements have shown that a more complicated relation exists between radiocarbon age and exact calendar age of samples than was assumed by Libby; the relation can be derived empirically by determination of radiocarbon contents of samples of known age. Causes for fluctuations of the C-14 activity of atmospheric CO (sub 2) are reviewed briefly. Work of tree-ring laboratories shoould make available precisely dated samples many thousand years old for use as an empirical correction table relating radiocarbon ages to true ages of the sample; radiocarbon and 0true ages for the last 2,000 years are tabulated. Only one C-14 age exwxists for each calendar year but a radiocarbon age may correspond to more than one true age.