[Psalm 73]

"Some scientists, however, believe that oil and gas originated in other ways, including chemical reactions between carbon dioxide and hydrogen below Earth' surface."

I've always thought that's a heck of a lot of petroleum to be formed from plants.
Coal perhaps, but not gazzillions of barrels of oil.

[Ingtar]

Jupiter’s atmosphere is composed of about 90% hydrogen and 10 % helium. There are only minute traces (0.07%) of methane (CH3), water, ammonia, and rock dust.

Since methane was one of those “biotic” materials under discussion, either there is life on Jupiter or methane is abiotic.

[R W Reactionairy]

There is much more coal than oil in terms of stored energy.

The processes for abiotic natural gas appear a lot more likely than for abiotic oil.

Finally, it does not make much difference how it is made. In addition to oil you still need a large enough trap [cap rock to keep it from rising — and something to keep it from migrating further horizontally] and suitable reservoir rock [porous and permiable] at a depth no so deep as to cook down the oil to have an economically viable deposit.