Based on radiometric dating, the oldest rocks scientists have found on Earth are 4.6 billion years old, but not ALL rocks are th
at old. Why might some rocks be 4.6 billion years old, and other rocks are only 2 billion years old, while yet others are only a few thousands years old?
Because similar to living things, some rocks are formed and it takes a long period to degrade them. During this period new rocks are born, some of these rocks can react with some compounds of the environment and can form new rocks or can be degraded.
What I try to say is that rock formation takes a lot of time and while some rocks disappear new rocks are created.
