Potassium argon dating wiki
When a material incorporates both the parent and daughter nuclides at the time of formation, it may be necessary to assume that the initial proportions of a radioactive substance and its daughter are known.
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 only in the number of neutrons in the nucleus.A particular isotope of a particular element is called a nuclide. That is, at some random point in time, an atom of such a nuclide will be transformed into a different nuclide by the process known as radioactive decay.Additionally, measurement in a mass spectrometer is subject to isotopic interference of other nuclides with the same mass number.Corrections may have to be performed by measuring isotopic ratios of elements which interfere with the target isotope.Poor vacuum permits gaseous atoms to intercept ionised atoms which are meant to be measured.
The resolution of the receptor is also a factor, but modern equipment is greatly improved on previous editions.
Also the argon-argon dating technique can be used for the potassium-argon sequence to ensure that no initial and half-life of the parent isotope, which can be obtained from tables such as the one given in : Although radiometric dating is accurate in principle, the precision is very dependent on the care with which the procedure is performed.
The possible confounding effects of initial contamination of parent and daughter isotopes have to be considered, as do the effects of any loss or gain of such isotopes since the sample was created.
In contrast to the most simple radiometric dating techniques, isochron dating, which can be used for many isotopic decay sequences (e.g.
rubidium-strontium decay sequence), does not require knowledge of the initial proportions.
In the ideal case, the material will incorporate a parent nuclide and reject the daughter nuclide.