lesbian speed dating ontario - Half life of potassium argon dating
These isotopes are stable, which is why they are with us today, but unstable isotopes are also present in minute amounts.About one carbon atom in a trillion (10) contains a radioactive nucleus with 6 protons and 8 neutrons — carbon 14.
This rare, unstable isotope is produced from ordinary nitrogen 14.
In earth's upper atmosphere, on the edge of what is commonly called outer space, light atomic nuclei from unknown sources outside of our solar system traveling at speeds approaching the speed of light called rain down continuously.
In the case of potassium-argon decay, this loss of a proton causes the atom to change from a reactive alkali metal to a non-reactive noble gas, which is an important characteristic.
Because argon is an inert gas, if it is not physically trapped in a rock, it will diffuse into the atmosphere.
Potassium argon (40K-40Ar) dating is a form of radiometric dating widely used because of the range of dates for which it is useful.