Formation During Nuclear Tests
The above-ground nuclear tests that occurred in several countries between 1955 and 1980 (see nuclear test list) dramatically increased the amount of carbon-14 in the atmosphere and subsequently in the biosphere; after the tests ended, the atmospheric concentration of the isotope began to decrease.
One side effect of the change in atmospheric carbon-14 is that this has enabled some options for determining the birth year of an individual, in particular, the amount of carbon-14 in tooth enamel, or the carbon-14 concentration in the lens of the eye.
Read more about this topic: Carbon-14
Famous quotes containing the words formation, nuclear and/or tests:
“Out of my discomforts, which were small enough, grew one thing for which I have all my life been grateful—the formation of fixed habits of work.”
—Elizabeth Stuart Phelps (1844–1911)
“We now recognize that abuse and neglect may be as frequent in nuclear families as love, protection, and commitment are in nonnuclear families.”
—David Elkind (20th century)
“The secret of a leader lies in the tests he has faced over the whole course of his life and the habit of action he develops in meeting those tests.”
—Gail Sheehy (b. 1937)