Mock nuke blasts go off.

Mock nuke blasts go off

A team of U.S. and Soviet scientists, using advanced monitoring equipment, recorded seismic waves from a trio of simulated nuclear explosions in Nevada last week, as part of an agreement between the Soviet Academy of Sciences and the Natural Resources Defense Council (NRDC), a Washington, D.C.-based environmental group. The experiment is aimed at demonstrating that seismic monitoring techniques can reliably detect nuclear explosions from underground weapons testing (SN: 4/16/88, p.245).

Although it will take several months to analyze the recordings, the scientists involved in the project believe the experiment will help determine how far high-frequency seismic waves can travel. From the initial results, it appears that two of the three blasts registered at the seismic stations closest to the explosions. But the farthest station, located several hundred kilometers away from the blasts, failed to detect any of the explosions, says Thomas Cochran, staff scientist for the NRDC. Because the explosions were tiny compared with nuclear blasts, the scientists did not expect the seismic waves to reach all stations.

The third blast registered only faintly at the closest stations, and scientists are analyzing the explosion to explain this surprising result.

The NRDC hopes these experiments will prod the U.S. government into negotiating a total ban on all nuclear weapons testing. At present, though, the administration is focusing on two treaties that limit nuclear tests to 150 kilotons of TNT. The Soviet Union and United States have signed but have not ratified the treaties, because they have yet to agree on how they will monitor compliance.