Radiometric dating calculator


The number of protons in the nucleus of an atom determines the element. For example, all carbon atoms have 6 protons, all atoms of nitrogen have 7 protons, and all oxygen atoms have 8 protons. The number of neutrons in the nucleus can vary in any given type of atom. So, a carbon atom might have six neutrons, or seven, or possibly eight—but it would always have six protons. An “isotope” is any of several different forms of an element, each having different numbers of neutrons. The illustration below shows the three isotopes of carbon.

Every park contains a slice of geologic time. In this classroom resource we highlight a few parks associated with each geologic time period.

Where t 1/2  is the half-life of the isotope carbon 14, t is the age of the fossil (or the date of death) and ln() is the natural logarithm function.  If the fossil has 35% of its carbon 14 still, then we can substitute values into our equation.


Radiometric dating calculator

Radiometric dating calculator



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