Intense heat under the earth surface can turn oil into vapour which is highly flammable and explosive. Remember the TWA 800 crash where the Boeing 747 plane was delayed on the runway. The air-conditioning heated up the fuel tanks turning fuel into vapour. When the giant plane was in mid-air a spark ignited the fuel vapours and the giant plane blow up in mid-air. What I have written is a possibility. I am not an expert. I know some people will say TWA 800 plane was blown up by a USA missile. Again a possibility. If anybody here know some experts ask them whether it is possible for Trillions of barrel of oil to catch fire under the earth surface.
There is no oxigen under the earth surface. So, there aren't gonna be any explosion till someone carelessly drills into such an oil reserve. Some of the gases that come out of volcanos can be flamable. So, large eruptions are a good indication of the worst-case scenario...
Just a childish temper tantrum from the Obomb pissed about losing the house, and trying to punish his perceived adversaries for it. The Obomb plays for the banking lobby, more repubs play for the oil lobby. That's how things work in Washington...