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.