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How has your research
actually benefited people? |
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| Speaking with Kobe high school students
in 1997 about the Great Hanshin-Awaji Earthquake. |
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In 1978, the government passed a law that called for
a stronger network for monitoring earthquake activity across the Tokai and
Kanto districts. The National Institute for Earth Science and Disaster Prevention
set about building a network to monitor seismic activity that might portend
a major earthquake in this area.
Plates move at a rate of up to 10 centimeters a year. We drew up a series
of cross-sections parallel to the movement of the plates--one for each 20-kilometer
segment--and on these we plotted the focus of each tremor we recorded. In
this way, we were able to show accurately how one plate slides under another.
Previously, it had been supposed that the interface where the Philippine
Sea Plate is sliding under the Pacific Plate was only 20 or 30 kilometers
in width, but the Ishida model revealed that it was actually closer to
100 kilometers. What this meant was that the worst possible earthquake in
the region was not in the range of magnitude 6, as previously thought, but
in the range of magnitude 7. So, this research has made a great contribution
to earthquake prediction as well as monitoring and disaster-prevention measures.
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| With researchers at the International Seismological Center in Britain (1999). |
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The Great Hanshin Earthquake that devastated Kobe in
1995 spotlighted the importance of disaster prevention. Until then, we had
poured most of our efforts into learning how to predict major quakes. But
in the wake of the Kobe Earthquake, there emerged a new field called real-time
seismology, which analyzes seismic waves right after a major earthquake
hits for information on the scale of the quake and characteristics of the
fault zone. The purpose is to calculate the intensity of the shaking that
has occurred in various areas and gauge the level of damage that is likely
to have occurred. This should help us target rescue efforts where they are
most needed, to keep casualties to a minimum. I took office as chair of
the Seismological Society of Japan directly after the Kobe quake, and I
set up a committee to review new areas of research, including such topics
as earthquake-resistant construction and disaster plans for local jurisdictions,
with an eye to making seismology more relevant to people's lives. |
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