The calcium-potassium age method is seldom used, however, because of the great abundance of nonradiogenic calcium in minerals or rocks, which masks the presence of radiogenic calcium.On the other hand, the abundance of argon in the is relatively small because of its escape to the atmosphere during processes associated with volcanism.
Ar (argon), the atom typically remains trapped within the lattice because it is larger than the spaces between the other atoms in a mineral crystal.
But it can escape into the surrounding region when the right conditions are met, such as change in pressure and/or temperature.
Thus, a granite containing all three minerals will record three different "ages" of emplacement as it cools down through these closure temperatures.
Thus, although a crystallization age is not recorded, the information is still useful in constructing the thermal history of the rock.
Potassium (K) is one of the most abundant elements in the Earth's crust (2.4% by mass).
One out of every 10,000 Potassium atoms is radioactive Potassium-40 (K-40).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.He applied heat to the nitrate and found that his sample contained small quantities of an unknown element with a low atomic weight.Spectral analysis showed 30 unique spectral lines, proving the existence of the new element.Ar) dating is a radiometric dating method invented to supersede potassium-argon (K/Ar) dating in accuracy.