On a more positive note, cosmic ray flux and the ensuing daughter products are used by geologists to date how long a particular rock has been buried or exposed.

On a more positive note, cosmic ray flux and the ensuing daughter products are used by geologists to date how long a particular rock has been buried or exposed. https://en.m.wikipedia.org/wiki/Surface_exposure_dating https://en.m.wikipedia.org/wiki/Surface_exposure_dating