In order to have a hydrocarbon reservoir, you need a source rock (usually shales-marine deposition) and a structural or stratigraphic trap to contain the migrating hydrocarbons. They are biogenic, they have manufactured them in the lab before. All you need is pressure and temperature and let it cook.

Technically oil and gas are renewable, it is going on right now, but the consumption rate is greater than replenishment. We think.

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