Los trilobitas dan aceite,aunque poco dan ademas si domesticas un ictinosaurio puedes ir rapidamente a por las rocas de aceite del agua
Just murder the sea pickles and get so much oil that America will want to know your location
This can be found in one of the genesis 2 space biome rotations, and is farmed from rocks that look like a 3 year old has tried to paint them black
Everyone needs oil for late-mid-game, so make yourself some fur armor and go to the snowy areas, there is usually alot of oil rocks on the beaches. Use a metal pickaxe to harvest oil.
Kill basilosaurus= infinite oil
I think basliosaur actually drop oil naturally if you take it, not sure tough.
Dung beetles make some oil of ya give them poop.
Kill tek dino and harvest the dead body with your tamed dino(raptor,rex etc)(omnivor type,)
There’s a bunch a black gloss rocks in the Arctic area, and those contain loads of oil. I recommend anky.
In the south west part of herbibore island there's a lot of trilobites, you can go down there with a spino and you will get chitin, oil, and pearls, is not the most efficent way but is the safest