The Pacific Northwest is facing a catastrophe that
could cause thousands of fatalities and tens of billions of dollars
of damage, an Oregon State University expert says-and despite
some progress made in the last few years to prepare for this,
a majority of people still don't seem to care.
Robert Yeats, a professor emeritus of geology at
Oregon State University and author of a new book titled "Living
With Earthquakes in the Pacific Northwest," (Oregon State
University Press, 320 pp., paperback $21.95) says the argument
is settled about whether or not this region is facing disastrous
earthquakes. The real issue now is whether enough is being done
at every level-government, building codes, disaster planning and
individual preparation-to prevent the massive loss of life and
economic devastation from the huge earthquake that, scientifically,
is a near certainty."The sheer size of the earthquake problem
dwarfs other concerns we face," Yeats says in the preface
of his book, which he said was written for the
general public as "part handbook, part scientific explanation,
part call-to-action." "In some respects, telling my
Northwest neighbors that we have an earthquake problem has been
like telling them about carpenter ants in the basement,"
Yeats wrote. "I began to feel like the watchman on the castle
walls, warning about the barbarians at the gate, begging people
to take me seriously."
For Yeats, his role as watchman and town crier is
the culmination of a distinguished scientific career in which
he was one of the very first experts to warn almost 15 years ago
that major earthquakes were a real concern for the Pacific Northwest
and not just something that happened in California. Since that
time, as study after study is done and the evidence begins to
mount in everything from buried salt marshes to Japanese tsunami
records, a surprisingly precise picture is beginning to emerge
about the risks faced from earthquakes in the Pacific Northwest.
It is not pretty, Yeats says. A major crustal fault
runs at shallow depths right under downtown Seattle that about
1,000 years ago apparently caused a magnitude 7 earthquake, big
enough if it were to recur today to cause catastrophic destruction.
Other significant faults, about which the activity level is less
clear, run next to downtown Portland and directly underneath Crescent
Valley High School outside Corvallis. There are literally hundreds
of mapped faults all over Oregon, Washington and southwestern
British Columbia, and probably many more that scientists don't
even know.
And then, of course, there's the Big One-the subduction
zone earthquakes which lurk off the shore of the Pacific Northwest,
which apparently last struck on a wintry January night in the
year 1700, which have an apparent recurrence interval of 200 to
1,000 years, and which average about every 500 years. "There
is a scientific consensus on the risk we face from a subduction
zone earthquake and there is now no serious doubt that we are
vulnerable," Yeats said. "Right now, the debate is primarily
whether a long section of the subduction zone fault will release
all at once, generating about a magnitude 9 earthquake, or in
separate segments that would yield magnitude 8 earthquakes."
That's an important debate, Yeats said, and one
that researchers may have an answer to within a few years. In
his book the question of a single magnitude 9 versus several magnitude
8 earthquakes is referred to as an "instant of catastrophe
or decade of terror." "A magnitude 9 subduction zone
earthquake could trash the whole Pacific Coast from Canada to
California and possibly wipe out the region's insurance industry,"
Yeats said. "In my own analysis I'm still a little bit on
the fence, but I lean towards the evidence that a magnitude 9
is most likely."
Yeats' book outlines all of these issues and more-the
basics of plate tectonics, the origin of earthquakes, the difference
between crustal and subduction zone earthquakes, the special risks
of tsunamis and soil liquefaction, earthquake insurance, government
planning, earthquake forecasting and prediction, building code
issues, and, of course, what average homeowners can do to help
prepare their dwelling and family for an earthquake.
"This book was written for the general public,
and I'm really hoping to raise public awareness about these issues
and get people to take them more seriously," he said. "The
book actually evolved from a course I taught at OSU in the university's
program to educate people on the impact of science and technology
on society. An informed citizenry is the real key to this issue
and many other problems."
Yeats is recognized as one of the world's premier
experts on earthquakes, especially those of the Pacific Northwest,
California and the Pacific Rim, and has traveled from the United
States to Japan, New Zealand, India and many other nations and
continents to study this geologic phenomenon. In 1984 he was among
the first scientists to begin warning of the potential
for great earthquakes in the Pacific Northwest.
As a result of those efforts and similar work by
many other scientists, Oregon now actually has made considerable
progress in preparing for this problem. The coast of the Oregon,
for instance, now has the highest "seismic activity"
ratings for purposes of building codes and other issues, the same
as those of southern California.
Yeats' book, which costs $21.95, can be ordered
on-line through http://osu.orst.edu/dept/press/LivingWithEar.html
or by calling 1-800-426-3797 in the USA . In Canada, call 1-800-663-5714.