Radiocarbon dating calibration

Vogel JC, Kronfeld J (1997) Calibration of radiocarbon dates for the late Pleistocene nsing U/Th dates on stalagmites. Radiocarbon 39 27-32... 

It is well known that the radiocarbon age does not correspond to the real calendar age of an organism, since Equation (16.2) is based on assumptions that are true only to a first approximation namely, the hypothesis of a constant value of 14/f0 over time in the past. [ 10] An accurate calibration curve[ll,12] has thus to be used to convert the tRC value of a measured sample into its true age. For a complete discussion on this topic, the already cited literature on radiocarbon dating can be considered for reference. In contrast, the focus of this chapter is on how to measure the radiocarbon age tRC, i.e. how to measure uR(t). Assuming, as explained above, 14/f0 and t in Equation (16.2) are known, it is indeed clear that a measurement of 14/ (f) allows us to determine the radiocarbon age. 

R.E. Taylor, History of radiocarbon dating, lecture presented at Radiocarbon in ecology and earth system science (http //ecology/botany/ufl/radiocarbon07/), University of California, Irvine (2006). (The first radiocarbon revolution is represented by the development of the dating method by Libby and his colleagues the second radiocarbon revolution is considered to be the introduc tion of calibration.)... 

One of the most interesting of the geophysics results from radiocarbon dates is the history of the sun. Apparently, it is registered in fluctuations of the cosmic ray intensity. These are fluctuations of rather short duration in terms of the radiocarbon lifetime, perhaps a century or so, and apparently they are caused by variations in the solar wind due to long-term changes in the solar emissions. This idea has been developed in some detail recently by Dr. Lai and his collaborators. It promises to give us a way of watching the history of the sun over tens of thousands of years. This fine structure on the curve of calibration was discovered by Dr. Suess and others. 

Calibration of the Radiocarbon Dating Time Scale, Radiocarbon. 22(3), 947-949 (1980). 

Figure 11. Hustedt pH categories (26), diatom-inferred pH values (weighted averaging), calibration radiocarbon dates, 210Pb dates, and pH periods in the history of Lilia Oresjon, southwest Sweden. Each bar and point represents one of the 700 samples analyzed from each 0.5-cm interval from the 350-cm-long core. (Reproduced with permission from reference 68. Copyright 1990 Royal Society of London.)...

Figure 2. Left Chronological table of Sardinian prehistory from the Middle Neolithic to the Middle Bronze Age, based on calibrated radiocarbon dates. Right Map of Sardinia with the location of the four sites where the skeletal remains tested were recovered.

Fig. 10. Fluorine profiles in samples from three different locations within the same burial place (Biiren a. A., Switzerland). The exposure age was determined by radiocarbon dating. The diffusion constants D were determined by evaluation of the left front of the fluorine profile. The values are calibrated. Samples from the same burial place show qualitatively similar profile shapes. Differences can be explained by material characteristics.

The calibration curve is rather precisely measured back to several millennia B.C, The error in conventional radiocarbon age can, in principle, be as small as 20-30 years. The calibration curve, however, does not fall monotonically with time. At times, two or three dates could give the same conventional radiocarbon age. For this reason, radiocarbon dating is particularly unworkable for the period from the mid 1600s (A.D.) to the present. 

Clark, R. M., Renfrew, C., "Tree-Ring Calibration of Radiocarbon Dates and the Chronology of Ancient Egypt, Nature (1973) 243, 266. 

Clark, R. M., A Calibration Curve for Radiocarbon Dates, Antiquity... 

Means of Calibrating Racemization Rates. Theoretically, the racemization technique has an eflFective dating range of 500,000 years in cool temperate environments. One problem in working with these older samples is finding an appropriate calibration sample. Radiocarbon-dated bones 17-20,000 years old provide suitable calibrations for the last... 

These various comparisons demonstrate that the Laguna skull radiocarbon date of 17,150 years is correct, that the dated Laguna material is indeed the original skull, and that the kasp value derived from the racemization and radiocarbon analyses of the Laguna skull can be used to calibrate the amino acid racemization reaction for the southern California coast. 

The so-called titanium method used by Arrhenius et a/. (1951) assumes a so-called lutite veil depositing at a constant rate throughout the deep oceans. Titanium associated with this lutite fraction then is also assumed to accumulate at a constant rate. Variations in the accumulation rates of biogenic components can then be assessed. The initial titanium method was calibrated by a single radiocarbon date as discussed above. The method has not been used since it was discovered that accumulation rates of all detrital and biogenic components of deep-sea sediments are subject to change as a function of climatic history and focusing processes. 

Calibration Correction of radiocarbon dates for the difference between calendar years and radiocarbon years. 

Study of very old trees, such as the bristlecone pines in California, have allowed researchers to develop calibration curves that adjust the results of radiocarbon dating experiments for the variation in the ratio that... 

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