How old is the average rock?

1 ⤊

How old is the average rock?

2007-03-27 06:14:56 · 2 answers · asked by 4knowreason 2 in Science & Mathematics ➔ Earth Sciences & Geology

2 answers

A really good question. If you averaged out the age of surface rocks over North America, you'd probably get an age somewhere around 200-300 million years, maybe a little more. I am discounting, of course, material being deposited this very day, and thinking only of lithified rocks. An average sample of the very surface (rock or not) of North America probably would be just a few million or so years of age (there is a lot of very young regolith atop bedrock).

2007-03-27 06:44:28 · answer #1 · answered by David A 5 · 1⤊ 0⤋

Hi. Less than a billion years old. On average.

2007-03-27 13:17:44 · answer #2 · answered by Cirric 7 · 0⤊ 0⤋