Don’t know about petroleum and gas, but the other main fossil fuel, coal, seems reasonably well documented.
There is more or less a continuum from peat, which is being laid down today in many places, through lignite to bituminous coal to anthracite.
Unless I’ve misunderstood something, which is quite possible.
So what? That has about as much relevance to oil as the scene in Kentucky Fried Movie where they are extracting oil from teenager's acne.