Seismic activity reported previous North Korea was a result of nuclear test
U.S. Geological Survey reported a seismic disturbance centered near the site of the secretive regime’s two previous nuclear tests. It appeared that North Korea conducted its third underground nuclear bomb on Today.
The epicenter of 4.9 disturbances has little or no history of earthquakes or natural seismic hazards, according to U.S. Geological Survey maps.
“It’s a nuclear test,” said Jeffrey Lewis, director of the East Asia Nonproliferation Program at the James Martin Center for Nonproliferation Studies at the Monterey Institute of International Studies. “That magnitude and that location — it’s awfully unlikely it’s anything else.”
Both of the previous detonations were considered small by the standards of nuclear testing in other countries.
President Obama asked Mr. Hu to curb North Korea after its second nuclear test in 2009; when Mr. Hu failed to do so, Obama excoriated him for showing “willful blindness“ to North Korea’s military actions.
North Korea was so secretive about the planned date for the test that they deliberately leaked and formally released vague information . Given its propensity for significant calendar days, experts say possibilities included Tuesday, the day of President Obama’s State of the Union address, or Saturday to celebrate the anniversary of the birth of Kim Jong-il, the father of the current leader, Kim Jong-un.
The first one in 2006 produced a tremor that measured a magnitude 4.1, and analysts in the U.S. later estimated its explosive force at less than one kiloton. The second one in 2009 produced a seismic tremor of 4.7 and an explosive force of about two to six kilotons, according to estimates by U.S. seismic and geological experts.
Estimates are in both cases are constrained by limited information about the geology of the mountains where the explosions took place. By contrast, the first nuclear bomb tested by the U.S. in 1945 had an explosive force of approximately 18 to 20 kilotons.
The reclusive, Stalinist state announced last month that it planned a new nuclear test and more long-range rocket launches, all of which it said were part of a new phase of confrontation with the United States.
“Obama has made clear that he would do whatever necessary to protect the security of its allies to counter North Korea’s threats and to defend American security interests,” Mr. Pollack said
U.S. analysts say North Korea’s first bomb test, in October 2006, produced an explosive yield at less than 1 kiloton (1,000 tons) of TNT. A second test in May 2009 is believed to have been about two kilotons, National Intelligence Director James Clapper told a Senate committee in 2012.
In Washington, a senior administration official said the United States was working to confirm a nuclear test.
In May 2012, North Korea said it had amended its constitution to formally proclaim itself a “nuclear state.”
The seismic disturbance took place at a time when several East Asian countries, including China, North Korea’s major ally, are observing public holidays for the Lunar New Year. It also took place less than 24 hours before President Barack Obama was due to make his State of the Union address.