A christian response to radiometric dating
This is consistent with the assumption that each decay event is independent and its chance does not vary over time.The solution is: where is the half-life of the element, is the time expired since the sample contained the initial number atoms of the nuclide, and is the remaining amount of the nuclide.Radiometric dating — through processes similar to those outlined in the example problem above — frequently reveals that rocks, fossils, etc.are very much older than the approximately 6,000 to 10,000 years reckoned by young earth creationists.It suffers from the problem that rubidium and strontium are very mobile and may easily enter rocks at a much later date to that of formation.This method for rock dating is based on the decay of potassium-40 into argon: until the rock solidifies, argon can escape, so it can in theory date the formation of rock.One way Young Earth Creationists and other denialists try to discredit radiometric dating is to cite examples radiometric dating techniques providing inaccurate results. Helens, creationists attempted discredit the discipline through dishonest practices.
Given isotopes are useful for dating over a range from a fraction of their half life to about four or five times their half life.Note that although carbon-14 dating receives a lot of attention, since it can give information about the relatively recent past, it is rarely used in geology (and almost never used to date fossils).Carbon-14 decays almost completely within 100,000 years of the organism dying, and many fossils and rock strata are hundreds of times older than that.To date older fossils, other methods are used, such as potassium-argon or argon-argon dating.Other forms of dating based on reactive minerals like rubidium or potassium can date older finds including fossils, but have the limitation that it is easy for ions to move into rocks post-formation so that care must be taken to consider geology and other factors.
Some isotopes have half lives longer than the present age of the universe, but they are still subject to the same laws of quantum physics and will eventually decay, even if doing so at a time when all remaining atoms in the universe are separated by astronomical distances.