Radiometric dating example problems
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.Another limitation is that carbon-14 can only tell you when something was last alive, not when it was used.A limitation with all forms of radiometric dating is that they depend on the presence of certain elements in the substance to be dated.Through analysis, a bone fragment is determined to contain 13% of its original carbon-14.The half-life of carbon-14 is approximately 5,730 years. Since the quantity represents 13% (or 13/100ths) of , it follows that This is based on the decay of rubidium isotopes to strontium isotopes, and can be used to date rocks or to relate organisms to the rocks on which they formed.
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.
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.
The oldest rock so far dated is a zircon crystal that formed 4.4-billion-years ago, which was only 200 million years or so after the Earth itself formed.
YEC biblical literalists are necessarily bound to the dogmatic religious conclusion that the Earth is of a certain age based on a particular literal interpretation of the Genesis creation myth.