The Horrible Methane Gas Disaster Scenario in the Gulf

This is not completely implausible:

With the emerging evidence of fissures, the quiet fear now is the methane bubble rupturing the seabed and exploding into the Gulf waters. If the bubble escapes, every ship, drilling rig and structure within the region of the bubble will instantaneously sink. All the workers, engineers, Coast Guard personnel and marine biologists measuring the oil plumes' advance will instantly perish.

As horrible as that is, what would follow is an event so potentially horrific that it equals in its fury the Indonesian tsunami that killed more than 600,000, or the destruction of Pompeii by Mt. Vesuvius.

The ultimate Gulf disaster, however, would make even those historical horrors pale by comparison. If the huge methane bubble breaches the seabed, it will erupt with an explosive fury similar to that experienced during the eruption of Mt. Saint Helens in the Pacific Northwest. A gas gusher will surge upwards through miles of ancient sedimentary rock—layer after layer—past the oil reservoir. It will explode upwards propelled by 50 tons psi, burst through the cracks and fissures of the compromised sea floor, and rupture miles of ocean bottom with one titanic explosion.

The burgeoning methane gas cloud will surface, killing everything it touches, and set off a supersonic tsunami with the wave traveling somewhere between 400 to 600 miles per hour.

While the entire Gulf coastline is vulnerable, the state most exposed to the fury of a supersonic wave towering 150 to 200 feet or more is Florida. The Sunshine State only averages about 100 feet above sea level with much of the coastline and lowlands and swamps near zero elevation. A supersonic tsunami would literally sweep away everything from Miami to the panhandle in a matter of minutes. Loss of human life would be virtually instantaneous and measured in the millions. Of course the states of Texas, Louisiana, Mississippi, Alabama and southern region of Georgia—a state with no Gulf coastline— would also experience tens of thousands, if not hundreds of thousands of casualties.

Loss of property is virtually incalculable and the days of the US position as the world's superpower would be literally gone in a flash...of detonating methane.

Obviously a worst case scenario, and I doubt it will happen... hard to believe exploding methane would have that much power to move so much water... but still, it's hard to say that it can't happen.

(thanks to j for the link)