N.J. In Path Of A Tidal Wave?
July 16, 2000 10:15 am EST

Pressurized Water Pockets Found Off Coast

NEW YORK (CBS News) - Could there be a tidal wave threat to New Jersey and the rest of the East Coast?

WCBS' Paul Murnane reports a computer simulation of the continental shelf 100 miles off the coast of New Jersey suggests that there may be pockets of water trapped under great pressure deep beneath the ocean floor.

The Penn State University study, by Peter B. Flemings and Brandon Dugan, concluded that if such pressurized deposits of water exist, they could pose a threat of sudden undersea landslides.

The researchers theorize that the water could be trapped deep in sediments on the edge of the continental shelf, a place on the sea bottom that is rather like the edge of a mountain top. In that area, the sea bottom drops steeply from a few hundred feet beneath the sea surface to several thousand.

The scientists said high pressure water trapped in the sediment could be released in a surge, or the water could seep out slowly, relieving the pressure. They said even a small shaking of a mild earthquake could be enough for a sudden release of the water.

If the water was released suddenly, explains Flemings, it could cause undersea landslides down the side of the continental shelf. Such slides, involving many tons of sediment falling like an undersea avalanche down the side of a submerged mountain, have been known to cause tidal waves.

In their study, the researchers used a computer simulation they developed and the techniques and analyses commonly used to help the oil industry predict the location of zones where water is trapped under high pressure in undersea sediment layers.

The Penn State researchers have not done calculations to predict when the high pressure zones could cause failures off New Jersey. Flemings says, "We have not tried to predict the probability of a significant failure but recognize that further research is warranted."