Potassiu m argon dating

01 Jan

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.

Potassium–argon dating, abbreviated K–Ar dating, is a radiometric dating method used in geochronology and archaeology.

The potassium-argon age of some meteorites is as old as 4,500,000,000 years, and volcanic rocks as young as 20,000 years old have been measured by this method.With 18 protons and 22 neutrons, the atom has become Argon-40 (Ar-40), an inert gas.For every 100 K-40 atoms that decay, 11 become Ar-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.