Undersea Mounds May Host Gas Pockets Ready to Burst

ByABC News
October 23, 2001, 3:09 PM

Oct. 31 -- When Edward A. Keller got his first look at some recent high resolution images of the ocean floor off Santa Barbara, Calif., he saw things that were surprising, exciting, and a little unsettling.

For openers, he saw what he believes to have been an ancient island, buried under the sea for thousands of years.

And he saw huge craters, one measuring at least 1,500 feet across, scattered along an earthquake fault zone like a series of open pits left behind by some aquatic miners.

He also saw mysterious mounds pushing up from the ocean floor, one more than 600 feet in diameter, and at first he didn't have a clue as to what they were. After many months of pondering the evidence, the UC Santa Barbara geologist is fairly convinced now that the mounds conceal pockets of gas that could rupture through the ocean floor with possibly disastrous consequences for anyone unfortunate enough to be directly over them.

A huge pocket of methane, suddenly bursting to the surface, would create a gaseous hole in the water so large that even an oil tanker could plunge into it and sink, Keller says.

"If enough bubbles come up, the water loses its buoyancy, and you can imagine a huge amount of methane coming up in a concentrated area," he adds. "If there was a boat there, it would lose its buoyancy and sink."

Is that very likely?

Probably not, Keller says.

"There's not a bunch of shipwrecks out there," he says.

Mysterious Deep Sea Slabs

But the fact that he can't rule it out has given rise to speculation that if the Earth burps at just the right time, ships and even airplanes suddenly deprived of oxygen because of a flood of methane might sink or fall out of the sky. There is even speculation that such events might explain the lost ships and aircraft in a region of the Atlantic known as the Bermuda Triangle, made famous by a pulp magazine article in 1968.

Adding to the speculation was the discovery of a sunken fishing boat near a sub sea crater off Great Britain in the North Sea. That crater looks very similar to the craters now known to lie off the coast of Santa Barbara.