Word: seismically
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Dates: during 1960-1969
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...Harvard government student, had some weird aspects. It would require the U.S. and Russia to deposit $5 billion apiece with the World Bank, as a sort of good faith deposit against discovery of an illegal underground blast within their boundaries. The evidence would come from many unmanned seismic recorders in sealed boxes scattered throughout the two countries. On every Wednesday (why this must be the day is not explained), each nation would fly the recorders to a neutral team on its frontier. Eventually, the records would be inspected by a panel of 15 scientists from neutral countries. If nine...
...they also argue-and some Western scientists agree-that human inspection is beside the point anyway: nuclear blasts can be detected by instruments placed beyond each nation's borders. That argument gained force last month when the Pentagon's Advanced Research Projects Agency reported new seismic detection techniques (TIME, July 20), which make it a lot easier than expected to distinguish a nuclear blast from an earthquake. Last week President Kennedy called an all-star White House conference of 16 officials, including the Vice President, the Secretaries of State and Defense and 13 others, to consider changing...
...produce signals equivalent to an underground nuclear explosion of given yield than had been expected." All by itself, that brief statement represented quite a switch; the Defense Department has usually favored the attitude that secret Russian underground tests could not be distinguished from natural earthquakes except by dozens of seismic stations spaced a few hundred miles apart on Communist territory...
...change of attitude seems to have been brought about by recent improvements in seismic instruments and methods of using them. One new method is to lower instruments as much as 10,000 ft. into abandoned oil wells. At this depth they are sheltered from surface noise and are five to ten times more sensitive to earth waves from bomb tests or earthquakes. Another promising system is to spread out many instruments in cross-shaped array on the surface of the earth. When their readings are compared to eliminate the effects of noise, traces of earth waves be come much clearer...
...detailed results of official U.S. and British experiments with new seismic instruments have not yet been made public, but nonofficial seismologists state emphatically that earthquakes and bomb tests are quite different, that they send distinctly different wave patterns through the earth. Another important difference is that most earthquakes are caused by rock movements many miles below the surface. This vertical distance can be measured accurately; if it is too great, the waves almost surely will not have come from a test. It is not likely, say the seismologists dryly, that even the most industrious Communists will explode secret tests...