Carbon dating study
Carbon-14 dating does not produce ages in the millions of years, as do some other types of radioisotope dating.
C dating consists of measuring the amounts of carbon-14 and carbon-12, and sometimes C-13, in a sample.
Int Cal09 and Marine09 radiocarbon age calibration curves, 0-50,000 years cal BP.  This was the scroll “Testament of Qahat,” for which the radiocarbon date was about two centuries older than the date based on paleography.
Carbon-dating of an ancient beam from a Guatemalan temple may help end a century-long debate about the Mayan calendar, say anthropologists.
In most cases, the three methods produced similar results.
Surprisingly, in at least one case the date range given by There may be other examples of systematic variation in isotope decay rates.
These effects are corrected for by comparing samples from different locations. The geophysical reservoirs include the atmosphere, the oceans, the biosphere, and the sediments.Violations of this assumption occur in the ocean reservoir due to the time required for mixing of surface waters with the deep layers.While the small variations in isotope decay that have been reported may not invalidate all isotopic dating, they raise questions about the assumption of completely uniform decay rates.A second assumption is that the sample being dated has not experienced any loss or contamination of C over its history.