Radioactive dating equation

Another possibility is spontaneous fission into two or more nuclides.While the moment in time at which a particular nucleus decays is unpredictable, a collection of atoms of a radioactive nuclide decays exponentially at a rate described by a parameter known as the half-life, usually given in units of years when discussing dating techniques.All ordinary matter is made up of combinations of chemical elements, each with its own atomic number, indicating the number of protons in the atomic nucleus.Additionally, elements may exist in different isotopes, with each isotope of an element differing in the number of neutrons in the nucleus.Radiometric dating is also used to date archaeological materials, including ancient artifacts.Different methods of radiometric dating vary in the timescale over which they are accurate and the materials to which they can be applied.The temperature at which this happens is known as the closure temperature or blocking temperature and is specific to a particular material and isotopic system.These temperatures are experimentally determined in the lab by artificially resetting sample minerals using a high-temperature furnace.

Isotopic systems that have been exploited for radiometric dating have half-lives ranging from only about 10 years (e.g., tritium) to over 100 billion years (e.g., samarium-147).For instance, carbon-14 has a half-life of 5,730 years.After an organism has been dead for 60,000 years, so little carbon-14 is left that accurate dating can not be established.Among the best-known techniques are radiocarbon dating, potassium–argon dating and uranium–lead dating.By allowing the establishment of geological timescales, it provides a significant source of information about the ages of fossils and the deduced rates of evolutionary change.