No one knows when the 'big one' might hit Cache Valley
By Jason A. Givens
December 12, 2006 | RICHMOND -- The experts don't know
when it's coming, but they all agree Utah is overdue
for a big earthquake.
Utah is ranked No. 9 on the United States Geological
Survey's top 10 states for earthquakes. However, that
doesn't mean the state has a lot of big earthquakes
like California, but it does have about 700 smaller
ones every year. In fact according to the USGS
Web site a small quake hit Cache Valley a little
over a week ago. While last week's earthquake was small
and probably not felt by anyone, scientists say a larger
earthquake could strike the valley.
said the potential magnitude of earthquakes in this
region is high 6s to low 7s, which he said is high enough
to be a cause for concern to people in the valley. He
said the Wasatch Front also has active faults, and earthquakes
from that region could cause damage in Cache Valley.
The most damaging earthquake to hit Cache Valley happened
Aug. 30, 1962; its magnitude was 5.7. Richmond was the
quake's epicenter, but it also caused significant damage
in Franklin, Lewiston, Logan and Preston, Idaho. The
earthquake caused an estimated $1 million damage and
Cache County was declared a disaster region by the Small
Richmond was the area that sustained the most damage.
Richard Bagley, who was 32 years old at the time, recalls
the loud rumbling sound the earthquake made. "It wasn't
really just that you felt it, you heard it as well,"
he said. "It was quite an unnerving thing."
Bagley, who was a teacher at North Cache High School,
said the earthquake damaged the school, toppled headstones
in the cemetery, destroyed several of the older homes
and damaged the LDS Benson Stake Tabernacle to the point
where it had to be torn down.
"It's such a helpless feeling," he said of his experience
during the earthquake. "You're wondering, 'What will
be the end result?' It was really a miracle that no
one got (seriously) physically injured."
Earthquakes have the potential to cause damage in
several ways. James Bay and Loren Anderson, professors
in USU's civil engineering department have studied earthquakes
extensively and helped map areas of concern for the
USGS. One of the areas in which they have done significant
research is liquefaction.
The Utah Geological Survey Web site
says liquefaction can occur when sandy soils saturated
with water are subjected to ground shaking caused by
an earthquake. The soil essentially liquefies and loses
strength and acts like quicksand rather than solid ground.
The outcome can cause extreme devastation, buildings
can sink into the ground or tilt, empty buried tanks
may rise to the surface, slopes can fail and several
other potentially hazardous events may occur.
Bay said liquefaction is quite common with larger
earthquakes and is a major cause for concern. He added
liquefaction occurred in the 1962 Cache Valley earthquake.
The Utah Geological Survey Web site points out that
liquefaction is a major hazard with earthquakes in Utah
and has been responsible for significant damage in several
earthquakes around the world. The valleys along the
Wasatch Front have a high vulnerability to liquefaction
due to susceptible soils, shallow ground water and a
relatively high probability of moderate to large earthquakes.
While liquefaction could be very damaging, Anderson
said the greatest damage would come from ground shaking
due to the large number of unreinforced masonry buildings
(typically brick buildings built before 1960).
In the event of an earthquake the University of Utah
Web site says the safest place to be is in an open
field where nothing can fall on you. "Earthquakes do
not injure or kill people; buildings and falling objects
do," the Web site says. The site recommends if you are
indoors, immediately take cover under a table or sturdy
piece of furniture. Do not attempt to run out of the
building or use stairs or an elevator.
Anderson recommends doing an inspection of your home
to locate potential hazards. Some of the things you
can do are anchor items such as large bookshelves and
water heaters to the wall, so they will not tip over
and cause injury. He added it is also a good idea to
remove objects near cribs that could fall and injure
As to when the next big earthquake will hit, Bay said,
"If it is going to happen this year or in the next 300
years, we really can't tell."