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On the Relationship Between Radiocarbon Dates and True Sample Ages

Published online by Cambridge University Press:  18 July 2016

Minze Stuiver
Radiocarbon Laboratory, Yale University, New Haven, Connecticut
Hans E. Suess
University of California, San Diego, La Jolla, California
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The result of a radiocarbon determination is commonly expressed as an age given in radiocarbon years. An error is usually assigned to each value as a measure of the statistical uncertainty of the measurement. Date lists published in this journal use a standard form of reporting dates and their errors (see Editorial Statements in Radiocarbon, v. 3 and v. 4). The conversion of a radiocarbon age, given in radiocarbon years B.P. (i.e., radiocarbon years elapsed since the origin of the sample) to a true calendar year makes necessary certain assumptions with respect to: (1) the half-life of C14, (2) the production rate of C14 by cosmic rays, (3) the size of reservoirs into which C14 is distributed and the exchange rate of this distribution. Libby (1955, p. 10) has shown that as an approximation one may assume that reservoir size and production and distribution rates, and therefore the C14 activity in atmospheric CO2 have been constant. However, the more accurate measurements of recent years have shown that at least one of these quantities must have varied with time. This means that a more complicated relationship exists between radiocarbon age and exact calendar age of a sample than had been assumed by Libby. This relationship cannot be determined theoretically, but can be derived empirically by determination of the radiocarbon contents of samples of known age. The following summarizes our present knowledge regarding differences between radiocarbon ages and true ages and the present status of the empirical calibration of the radiocarbon time scale.

Research Article
Copyright © The American Journal of Science 


Bien, G., Rakestraw, N. W., and Suess, H. E., 1963, Radiocarbon dating of the deep water of the Pacific and Indian Ocean: Radioactive Dating, Athens. Greece. Symp. 159–173, IAEA, Vienna, Proc.; Bull. Inst. Ocean., Monaco, v. 61.Google Scholar
Damon, P. E., Long, A., and Grey, D. C., 1966, Fluctuation of atmospheric carbon-14 during the last six millenia: Jour. Geophys. Research, v. 71, p. 10551064.Google Scholar
De Vries, Hl., 1958, Variations in concentration of radiocarbon with time and location on earth: Koninkl. Ned. Akad. Wetensch. Prodc. B61, p. 94102.Google Scholar
Elsasser, W. E., Ney, P., and Winckler, J. R., 1956, Cosmic-ray intensity and geomagnetism: Nature, v. 178, p. 12261227.Google Scholar
Hughes, E. E., and Mann, W. B., 1964, The half-life of carbon-14: comments on mass-spectroscopic method: Internat. Jour. Appl. Rad. Iso., v. 15, p. 97100.Google Scholar
Karlen, I., Olsson, I. U., Kallberg, P., and Kilicci, S., 1964, Absolute determination of the activity of two C14 dating standards: Arkiv för Geofysik, v. 4, p. 465471.Google Scholar
Keeling, C. D., 1958, The concentration and isotopic abundances of atmospheric carbon dioxide in rural areas: Geochim. et Cosmochim. Acta, v. 13, p. 322334.Google Scholar
Keeling, C. D., 1961, The concentration and isotopic abundances of carbon dioxide in rural and marine air: Geochim et Cosmochim. Acta, v. 24, p. 277298.Google Scholar
Kigoshi, K. and Hasegawa, H., 1965, Secular variations of atmospheric radiocarbon concentration and its dependence on geomagnetism: Jour. Geophys. Research, v. 71., p. 10651072.Google Scholar
Libby, W. F., 1955, Radiocarbon Dating: Chicago, University of Chicago Press.Google ScholarPubMed
Libby, W. F., 1963, Accuracy of radiocarbon dates: Science, v. 140, p. 278.Google Scholar
Lingenfelter, R. E., 1963, Production of carbon-14 by cosmic-ray neutrons: Revs. Geophysics, v. 1, p. 1.Google Scholar
Mann, W. B., Marlow, W. F., and Hughes, E. E., 1961, The half-life of carbon-14: Jour. Appl. Rad. Iso., v. 11, p. 5767.Google Scholar
Olsson, I. U., Karlén, I., Turnbull, A. H., and Prosser, N. J. D., 1962, A determination of the half-life of C14 with a proportional counter: Arkiv for Fysik, v. 22, p. 237255.Google Scholar
Olsson, I. U., Karlén, I., 1963, The half-life of C14 and the problems which are encountered on absolute measurements on beta-decaying gases: Radioactive Dating, IAEA, Vienna.Google Scholar
Revelle, R., and Suess, H. E., 1957, Carbon dioxide exchange between atmosphere and ocean: Tellus, v. 9, p. 18.Google Scholar
Schove, D. J., 1955, The sunspot cycle 649 B.C. to 2000 A.D.: Jour. Geophys. Res., v. 60, p. 126145.Google Scholar
Stuiver, M., 1961, Variations in radiocarbon concentration and sunspot activity: Jour. Geophys. Res., v. 66, p. 273276.Google Scholar
Stuiver, M., 1965, Carbon-14 content of 18th and 19th century wood: variations correlated with sunspot activity: Science, v. 149, p. 533535.Google Scholar
Suess, H. E., 1954, Natural radiocarbon and the rate of exchange of carbon dioxide between the atmosphere and the sea: Williams Bay Conf. September 1953, Proc., NAS-NSF Pub., p. 52.Google Scholar
Suess, H. E., 1960, Secular changes in the concentration of atmospheric radiocarbon: Conf. on Problems Related to Interplanetary Matter, Highland Park, Illinois, Proc., Nuclear Science Series Report No. 33, NAS-NRC, Washington, D. C., Pub. 845, p. 90.Google Scholar
Suess, H. E., 1965, Secular variations in the cosmic-ray-produced carbon-14 in the atmosphere and their interpretations: Jour. Geophys. Res., v. 70, p. 59375951.Google Scholar
Suess, H. E., 1966, Climatic changes, solar activity, and the cosmic ray production rate of radiocarbon: Meteorological Monographs, in press.Google Scholar
Vogel, J. C., 1965, Carbon-14 content of wood from different locations: Internat. C14 and H3 Conf., Pullman, Washington, Proc.Google Scholar
Wood, L. and Libby, W. F., 1964, Geophysical implications of radiocarbon date discrepancies: Isotopic and Cosmic Chemistry, Craig, Miller and Wasserberg, , eds., North-Holland Pub. Co., Amsterdam, p. 205210.Google Scholar