Carbon dating cycle
Radiocarbon dating needed an organic material that was not contaminated with carbon 14 from fossil fuel burning or nuclear weapons testing. Its radiocarbon content was theoretically the same as a wood sample grown in AD 1950, the zero point of the radiocarbon timescale used in quoting carbon dating results.Even after nuclear weapon testing was banned, the bomb effect still remains.They found out that tree rings do not exchange radiocarbon with other tree rings.This fact has supported the use of dendrochronology in radiocarbon dating, particularly in constructing radiocarbon calibration curves.The bomb effect refers to the phenomenon that produced “artificial” radiocarbon in the atmosphere due to nuclear bombs.Nuclear weapons testing brought about a reaction that simulated atmospheric production of carbon 14 in unnatural quantities.Bomb carbon is essentially an artificial injection of carbon 14.
The radiocarbon dating method is based on certain assumptions on the global concentration of carbon 14 at any given time.
There are two human activities recognized to have irreparably changed the global radiocarbon levels—the burning of fossil fuel and nuclear weapons testing.
Burning of large quantities of fossil fuels like coal, referred as the Suess effect, had significantly lowered the radiocarbon concentration of the atmospheric carbon reservoir.
According to literature, nuclear weapons testing in the 1950s and 1960s have nearly doubled the atmospheric carbon 14 content as measured in around 1965.
The level of bomb carbon was about 100% above normal levels between 19.
Results of the study have enabled modelers to analyze the pathway of radiocarbon and its exchange and residence times.