Process uranium dating
It has become increasingly clear that these radiometric dating techniques agree with each other and as a whole, present a coherent picture in which the Earth was created a very long time ago.
This makes it great for archaeology - at least, up to 50,000 years ago - but not so much for much else.
I can’t remember the effective range of dates on this one, but it’s a shorter term (tens to hundreds of thousands of years) method.
There are a bunch of other isotopic systems that are good for anywhere from tens of millions through billions of years.
Some of the atoms eventually change from one element to another by a process called radioactive decay.
If there are a lot of atoms of the original element, called the parent element, the atoms decay to another element, called the daughter element, at a predictable rate.