Where do you think the liquid methane oceans on Titan came from?
We’re talking about earth and the hydrocarbons that include carbon isotopes found in living things.
Won’t find that on titan.
Won’t get oil reserves from dinosaurs either because when they die they die above ground so anything close to oil in them dries up and is broken down by UV light.
It comes from worms. Short lifespan. Gazillions of them. Living worms are indeed found at drilling depth.