Seismic Readings Suggestive of Low Magnitude of N-Test

The North Korea’s nuke test was relatively small, suggests an initial seismic readings from the underground blast. However, it will take US and international organizations conclude if it was a nuclear detonation and how successful it might have been, experts said.

It should be mentioned that scientists can gauge the size of an underground nuclear blast by how violently it shakes the earth, though this is not a foolproof method because conventional explosives can mimic the rumble. Experts can confirm the atomic origin by detecting the signature of radioactive gases and particles that a nuclear blast emits.

According to the reports of the United States Geological Survey, the Monday’s test had a magnitude of 4.7, a slightly larger than the one that the North Koreans generated in October 2006. At that point of time, many experts had considered that atomic blast a near flop, and they wondered the same about Monday’s test.

“We’ll have to wait for more analysis of the seismic data, but so far the early news media reports about a ‘Hiroshima-size’ nuclear explosion seem to be overblown,” said Hans M. Kristensen, a nuclear expert at the Federation of American Scientists.

Annika Thunborg, a spokeswoman in Vienna for the preparatory commission for the Comprehensive Nuclear Test Ban Treaty Organization, said in an interview that 39 of the organization’s tracking stations had detected the seismic event, and that the commission had judged its magnitude to be 4.5.

The primitive bombs dropped on Hiroshima and Nagasaki had explosive yields of 15 kilotons and 22 kilotons, respectively.

A senior Obama administration official said Monday afternoon that based on seismic data alone, officials estimated the explosion at “several kilotons.” That would be a major advance beyond the 2006 test. However, senior American officials still had not seen any results of environmental sampling that might reveal details of the blast and confirm that it was nuclear.