system
Given the following post, respond as if you're commenting on Reddit:
human
Since plastic is NOT biodegradable, millions of years into the future will there be layers of plastic in the rock?

As in, you would find minerals deposits scattered around made of plastic.  Like they would call it something like the Plasteozoic Era.  Or will plastic eventually break down a different way?
gpt
You shouldn't, or at least not much. Plastic is photodegradeable, chemodegradeable, and thermodegradeable. Some plastics can oxidize, and some just plain spontaneously break down slowly. Millions of years is an awfully long time. It's not likely that you would easily find *any* organic polymers in rock layers in millions of years. In some places You'd probably find preserved plastic, but in those same types of environments we find bits of preserved DNA, RNA, and protein polymers that are millions of years old. 

Edit: forgot to mention that we are finding that some organisms can in fact biodegrade plastics.