Radiocarbon Dating (C-14)
Definition
Age determination from the ratio of radioactive carbon-14 to stable carbon-12 in organic material. Atmospheric C-14 spiked during nuclear testing (1950s-1960s), allowing ivory or tissue formed after c. 1955 to be dated to within 1-2 years using the bomb-curve calibration.
- Basis
- C-14 to C-12 ratio decay
- Bomb-curve window
- Material formed after c. 1955
- Bomb-curve precision
- Within 1 to 2 years
- Application
- Ivory and tissue age estimation
Common questions
Why is the atmospheric nuclear-testing spike useful for forensic dating?+
Above-ground nuclear tests roughly doubled atmospheric C-14 levels between the 1950s and mid-1960s, then it declined on a well-documented curve after the Partial Test Ban Treaty, so material formed during that window carries a distinctive, precisely dateable signature.
Can bomb-curve radiocarbon dating be used on material formed before the 1950s?+
Not with the same precision. Before the nuclear-testing spike, atmospheric C-14 levels changed slowly and require conventional radiocarbon calibration curves, which give much coarser age estimates than the sharp bomb-curve method.
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