Define isotopic dating
any method of determining the age of earth materials or objects of organic origin based on measurement of either short-lived radioactive elements or the amount of a long-lived radioactive element plus its decay product.
A method for determining the age of an object based on the concentration of a particular radioactive isotope contained within it.
Most elements exist in different atomic forms that are identical in their chemical properties but differ in the number of neutral particles—i.e., neutrons—in the nucleus.
For a single element, these atoms are called isotopes.
Thus, discretion and interpretation of age dating is essential.
Ar after cooling past the closing temperature and that this was properly sampled during analysis.
Radiocarbon dating is one kind of radiometric dating, used for determining the age of organic remains that are less than 50,000 years old.
For inorganic matter and for older materials, isotopes of other elements, such as potassium, uranium, and strontium, are used.
The gas may include atmospheric gases, such as carbon dioxide, water, nitrogen, and argon, and radiogenic gases, like argon and helium, generated from regular radioactive decay over geologic time.
This technique allows the errors involved in K-Ar dating to be checked.
Argon–argon dating has the advantage of not requiring determinations of potassium.
The abundance of Ar is unlikely to provide the age of intrusions of granite as the age typically reflects the time when a mineral cooled through its closure temperature.
However, in a metamorphic rock that has not exceeded its closure temperature the age likely dates the crystallization of the mineral.
Dating of movement on fault systems is also possible with the Ar method.