Two or More Explosions

By David Ruppe

ABCNews.Com 18 August 2000

The Russian submarine Kursk was rocked by two or more explosions before diving to the floor of the Barents Sea, U.S. military and civilian scientists said. And while analysts caution they still do not have enough information to determine what might have caused the submarine and its 118 crew to get to the bottom of the Barents Sea last Saturday, they say the information does suggest possibilities.

Preliminary analysis of readings from a seismographic station in Norway suggest an initial explosion of a magnitude of one-tenth of ton or less of TNT, Prof. John Wallace, a geo-scientist at the University of Arizona, tells Then, about two minutes later, a second sound was recorded suggesting a much larger blast registering about 3.47 on the Richter scale. That suggests a force of roughly 1 ton of TNT, according to a preliminary analysis by Wallace, who has posted the readings on his Web site (see Web link, right). Pentagon experts say the second reading indicates a force of around 2 tons of TNT.

Seismic stations as far away as Canada, Germany and Alaska recorded the events. But scientists are paying particular attention to sounds recorded by Norwegian stations, part of a global network, which were closest to the sub and may provide the most reliable readings.

Possible Preliminary Explanations

Analysts caution it’s much too early to draw conclusions about what might have caused the accident. But they say initial analysis of the readings, however imprecise, do suggest certain scenarios.

The first, smaller reading “certainly would be consistent with what you might expect from either a torpedo or cruise missile warhead exploding,” says John Pike, of the Federation of American Scientists, adding, “it would not exclude bumping in to an old WWII sea mine.” The second recorded sound or sounds, says Pike, would be consistent with single or multiple near simultaneous torpedo or cruise missile explosions — or possibly the collapse of one or more pressurized bulkheads. From the two-minute delay, he says, “one could speculate that the initial explosion caused a fire in the torpedo room, and that that set off another weapon, or weapons or that initial explosion breached part of the hull, which damaged another pressure bulkhead subsequently causing it to collapse.”

Time May Tell

Clay Moltz, a professor at the Monterrey Institute for International Studies in California, says images taken of damage to the sub would be consistent with the theory that a torpedo explosion was the initial cause. “It’s consistent with the small number of cases that we have of submarine accidents, because of where the blast was, what we know about the damage, and because of the fact that it took place during an exercise where we know they were firing torpedoes,” he says. Moltz believes a mine would be less likely considering how far from shore the incident happened and how old the mine would probably be.

At a briefing Thursday, Pentagon spokesman Rear Adm. Craig Quigley declined to comment on what U.S. authorities believe might have caused the accident.

Experts say the calculations about the size of the explosions, based on the seismic readings, are not extremely precise. “I would say there is some non-trivial uncertainty in these yield estimates,” says Pike.

Wallace says he’s working on further honing his analysis: “Tonight we’ll do the full processing on it.”