[Cincinatus]

It's very difficult to synthesize all of the complex organic molecules that make up petroleum from simple CO2. If you're right, then Mars should have massive petroleum deposits in its crust. Maybe Exxon can sponsor the next Mars mission!

[RightWhale]

Mars should have massive petroleum deposits in its crust.

What are we waiting for? Halliburton should be on their way now. Oh, wait, the lightweight fractions would be gone, we aren't talking light, sweet crude. Probably just bitumen. Well, we can blacktop the road to Cydonia, anyway.

[El Gato]

It's very difficult to synthesize all of the complex organic molecules that make up petroleum from simple CO2.

Methane isn't CO2, it's CH4. CO2 is, as it says, Carbon DiOxide.