Seismic
action felt in geology department
By Cassady Jeremias
On-line Forty-Niner
 A
brand new $72,000 piece of equipment sits
in a box tucked in a corner on the basement
floor of the Peterson Hall Science Building
3, waiting for the earth to move.
The geological sciences department’s new
seismograph was placed there thanks to grants
from the Alumni Association, Cal State Long
Beach President Robert Maxson, the geology
department and a $60,000 donation from the
company that built it, Kinemetrics.
“Students can now see in real time an earthquake
happening. There is a tremendous amount
of seismic activity going on that we can’t
feel that the seismograph picks up,” James
McKibben, the Science Learning Center director
said.
The new seismograph is not made of pens
writing zig zag lines on a moving drum,
buried in the earth. That method has become
obsolete according to Robert Francis, a
professor in the geology department.
Instead, the actual machine is encased in
a tiny box the size of a videocassette tape.
Inside is a small spring loaded weight that
moves in response to ground movement and
is measured by electronic circuit. The tiny
machine is able to detect much finer amounts
of movement, including non-earthquake movement,
such as heavy trucks going by.
“You get a visual display, now you can see
even the smallest little tick on it,” Scott
Singley, senior geology major, said.
For this reason, the information gathered
at CSULB is sent via the Internet to the
Scripps Institute of Oceanography in San
Diego where it is compared with approximately
15 other seismograph recordings in Southern
California. When information from a number
of places match, it is a sign of an earthquake.
A Satellite Global Positioning system link
is also part of the package, connected through
a cable directly to the seismograph and
provides a time reference within five microseconds.
By having information linked and almost
instantly traceable, scientists can pinpoint
an epicenter with a minimum of three stations.
“It’s like drawing three circles, and the
three circles intersect at some point,”
Francis said.
California has many faults all over the
state, including the San Andreas, which
runs down the entire length of the state.
Nearby, the Newport Inglewood fault, the
San Jacinto fault and the Elsinore fault
make activity frequently.
Thursday morning Francis stared intently
at the computer screen delighted to have
some activity to explain.
“This one was about five kilometers deep,
about magnitude three,” he said. It hit
near the Santa Barbara Ventura area around
9:30 a.m.
The seismograph hooked up to two colorful
flat screen monitors shows data of Southern
California’s seismic activity so precisely
that you can tell by a colored square on
the screen how often an earthquake occurs,
updated almost instantly, including minor
quakes that no one feels.
“Minor events take the stress off the fault
and lessen the chance of a truly large quake,”
McKibben said.
However, faults do tend to go in cycles,
as do many things in nature McKibben explained.
The San Andreas Fault has approximately
157-year intervals, the last big one hit
in San Francisco in 1989, but many other
quakes have been branches of this fault.
There are also faults still unknown, as
discovered in the Northridge quake in 1994.
The department plans to set up another monitor
in the hallway of the geology building,
so anyone who passes by can see the current
seismic activity. One will also be set up
in a classroom where the beginning geology
classes meet.
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