What is radiometric dating and do scientists use it in the field of geology?

To establish the age of a rock or a fossil, researchers use some type of clock to determine the date it was formed. Geologists commonly use radiometric dating methods, based on the natural radioactive decay of certain elements such as potassium and carbon, as reliable clocks to date ancient events.

They use it to date rocks that are old and find the age. its not always accurate but close enough