Carbon 14 dating used archaeology

18 Oct

Fortunately, Willard Libby, a scientist who would later win the 1960 Nobel Prize in Chemistry, developed the process known as radiocarbon dating in the late 1940s. In a nutshell, it works like this: After an organism dies, it stops absorbing carbon-14, so the radioactive isotope starts to decay and is not replenished.

Archaeologists can then measure the amount of carbon-14 compared to the stable isotope carbon-12 and determine how old an item is.

Regardless of the particular 14C technique used, the value of this tool for archaeology has clearly been appreciated.In contrast to relative dating techniques whereby artifacts were simply designated as "older" or "younger" than other cultural remains based on the presence of fossils or stratigraphic position, 14C dating provided an easy and increasingly accessible way for archaeologists to construct chronologies of human behavior and examine temporal changes through time at a finer scale than what had previously been possible.The application of Accelerator Mass Spectrometry (AMS) for radiocarbon dating in the late 1970s was also a major achievement.Carbon-14 has a half-life of 5,730 ± 40 years— during the succeeding 5,730 years.Because carbon-14 decays at this constant rate, an estimate of the date at which an organism died can be made by measuring the amount of its residual radiocarbon.