When you need oil on abberation, you should go to the spine not the surface, the surface will burn you and you only get like 3 oil for it, but in the spine it will give you hundreds of it. Or just use your dung beetle I don’t care anymore.
Mining drill and a good wyvern is my favorite way the shiny black rocks along north coast and on icebergs on the island will yeald decent amount of oil and quickly much better then swimming to bottom of ocean
In genises I recommend building a Ocean platform and putting like 4 x basilorsauruses there or tusos(giant squid) and each one will produce 20 oil for you but watch out it quickly spoils and its called ink but it works the same as oil
There are many ways to obtain oil. My personal favorite is, to run around and tame a few Tek creatures. Kill their babies or the wild ones and harvest them with a chainsaw, if you don’t have one use a hatchet. If you need oil over a long timespan just tame a few Tek creatures an let them breed. Kill their babies and youll get a lot of oil and some great side products like meta scrap, wich is a great equivalent to metal. If you don’t have the time or nerves to do that you can just go to the ice biome and destroy the big black rocks (our intended) and youll get a lot of oil in a short time (the only problem is the transportation of yourself and the oil from the ice biome to your base)