Kris Hirst Definition: Radiocarbon dating uses the amount of Carbon 14 (C14) available in living creatures as a measuring stick.
Radiocarbon dating of the carbonate remaining in calcined bones is widely regarded as a viable alternative to date skeletal remains in situations where collagen is no longer present.
However, anomalously low δ13C values measured in calcined bones prompted questions about the origin of the carbon used for dating.
The goal of this study was to quantify the magnitude of carbon isotope exchange between bone carbonate and environmental CO2 for bones calcined under natural conditions.
Because of the rates of decay, radiocarbon dating is not useful for sites older than 50,000 years old.
Archaeological sites older than that period must rely on alternative means of dating.
For more detailed information on this and other dating techniques used in archaeology, see the Dating in Archaeology Short Course.
This glossary entry is part of the Dictionary of Archaeology.
So, for example, if a tree was used as a support for a structure, the date that tree stopped living (i.e., when it was cut down) can be used to date the building's construction date.
Studies have indicated that the amount of carbon in the atmosphere has not remained constant, and beginning about 1500 BC, dates provided by radiocarbon are too recent.
These dates become farther off the older the time is indicated.
Calibration of radiocarbon dates to offset the error is accomplished by a fairly complicated set of formulas, but they primarily use comparison to dendrochronology dating referents.