How do we know how old rocks are?

Thermochronic is gettin' geochronic over at Apparent Dip with a wonderful post about geochronology that even I can understand.

If you are scientist and have family members or friends asking you to explain how we date rocks then read, bookmark, and re-read that post.

If you are not a scientist and just simply want to know for yourself, I think you'll find it informative and understandable.

Plus, it has M&M's involved in the explanation!