An explanation for some of the disappearances focuses on the presence of vast fields of methane hydrates on the continental shelves. A paper was published in 1981 by the United States Geological Survey about the appearance of hydrates in the Blake Ridge area, off the southeastern United States coast. Periodic methane eruptions may produce regions of frothy water that are no longer capable of providing adequate buoyancy for ships. If this were the case, such an area forming around a ship could cause it to sink very rapidly and without warning. Laboratory experiments have proven that bubbles can, indeed, sink a scale model ship by decreasing the density of the water.
Hypothetically, methane gas might also be involved in aircraft crashes, as it is not as dense as normal air and thus would not generate the amount of lift required to keep the aircraft flying. Low levels of methane have also been shown to cause an aircraft engine to stall when added to the intake of air.
