Absolute dating methods determine how much time has passed since rocks formed by measuring the radioactive decay of isotopes or the effects of radiation on the crystal structure of minerals. Paleomagnetism measures the ancient orientation of the Earths magnetic field to help determine the age of rocks.

What is the meaning of absolute dating?

Absolute dating is the process of determining an age on a specified chronology in archaeology and geology. Absolute dating provides a numerical age or range, in contrast with relative dating, which places events in order without any measure of the age between events.